WO2007072588A1 - 比較器及びa/d変換器 - Google Patents
比較器及びa/d変換器 Download PDFInfo
- Publication number
- WO2007072588A1 WO2007072588A1 PCT/JP2006/308143 JP2006308143W WO2007072588A1 WO 2007072588 A1 WO2007072588 A1 WO 2007072588A1 JP 2006308143 W JP2006308143 W JP 2006308143W WO 2007072588 A1 WO2007072588 A1 WO 2007072588A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- voltage
- comparator
- differential
- reset
- clock signal
- Prior art date
Links
Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03M—CODING; DECODING; CODE CONVERSION IN GENERAL
- H03M1/00—Analogue/digital conversion; Digital/analogue conversion
- H03M1/06—Continuously compensating for, or preventing, undesired influence of physical parameters
- H03M1/0602—Continuously compensating for, or preventing, undesired influence of physical parameters of deviations from the desired transfer characteristic
- H03M1/0604—Continuously compensating for, or preventing, undesired influence of physical parameters of deviations from the desired transfer characteristic at one point, i.e. by adjusting a single reference value, e.g. bias or gain error
- H03M1/0607—Offset or drift compensation
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K5/00—Manipulating of pulses not covered by one of the other main groups of this subclass
- H03K5/22—Circuits having more than one input and one output for comparing pulses or pulse trains with each other according to input signal characteristics, e.g. slope, integral
- H03K5/24—Circuits having more than one input and one output for comparing pulses or pulse trains with each other according to input signal characteristics, e.g. slope, integral the characteristic being amplitude
- H03K5/2472—Circuits having more than one input and one output for comparing pulses or pulse trains with each other according to input signal characteristics, e.g. slope, integral the characteristic being amplitude using field effect transistors
- H03K5/2481—Circuits having more than one input and one output for comparing pulses or pulse trains with each other according to input signal characteristics, e.g. slope, integral the characteristic being amplitude using field effect transistors with at least one differential stage
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03M—CODING; DECODING; CODE CONVERSION IN GENERAL
- H03M1/00—Analogue/digital conversion; Digital/analogue conversion
- H03M1/12—Analogue/digital converters
- H03M1/20—Increasing resolution using an n bit system to obtain n + m bits
- H03M1/202—Increasing resolution using an n bit system to obtain n + m bits by interpolation
- H03M1/203—Increasing resolution using an n bit system to obtain n + m bits by interpolation using an analogue interpolation circuit
- H03M1/204—Increasing resolution using an n bit system to obtain n + m bits by interpolation using an analogue interpolation circuit in which one or more virtual intermediate reference signals are generated between adjacent original reference signals, e.g. by connecting pre-amplifier outputs to multiple comparators
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03M—CODING; DECODING; CODE CONVERSION IN GENERAL
- H03M1/00—Analogue/digital conversion; Digital/analogue conversion
- H03M1/12—Analogue/digital converters
- H03M1/34—Analogue value compared with reference values
- H03M1/36—Analogue value compared with reference values simultaneously only, i.e. parallel type
- H03M1/361—Analogue value compared with reference values simultaneously only, i.e. parallel type having a separate comparator and reference value for each quantisation level, i.e. full flash converter type
- H03M1/362—Analogue value compared with reference values simultaneously only, i.e. parallel type having a separate comparator and reference value for each quantisation level, i.e. full flash converter type the reference values being generated by a resistive voltage divider
Definitions
- the present invention receives a plurality of differential voltage pairs and performs a comparison operation for each differential voltage of the plurality of differential voltage pairs in synchronization with a clock signal, and an analog signal as a digital signal
- the present invention relates to an AZD converter that converts to, particularly an AZD converter having a parallel configuration.
- FIG. 14 shows a configuration of a parallel AZD variant 1400 in the prior art. Using this AZD converter, high-speed analog Z-digital conversion was performed.
- the AZD conversion 1400 includes a reference voltage generation circuit 1401, a differential amplifier row 1402, a comparator row 1404, and an encoding circuit 1405.
- the reference voltage generation circuit 1401 generates reference voltages VRl to VRn + 1 by dividing a voltage between the high-voltage side reference voltage 1401a and the low-voltage side reference voltage 1401b by a plurality of resistors Rl to Rn.
- the reference voltages VRl to VRn + 1 are input to the differential amplifier row 1402.
- the differential amplifier row 1402 has n + 1 differential amplifiers, and is parallel to a predetermined relationship between the analog input signal voltage input from the analog input signal voltage input terminal AIN and the reference voltages VRl to VRn + 1. Amplify and input to comparator row 14 04.
- the comparator row 1404 compares the outputs of the differential amplifier row 1402 in parallel.
- the encoding circuit 1405 logically processes (converts) the comparison result output from the comparator array 1404 and outputs a digital signal DOUT having a predetermined resolution.
- the n is about 2 to the Nth power.
- a conventional AZD converter having a parallel configuration as described above is capable of simultaneously comparing a reference voltage and an analog input signal voltage in parallel as compared to an AZD converter such as an integral type or a series-parallel type. Therefore, it has the advantage that AZD conversion is possible at high speed.
- the resolution of AZD conversion is increased by 1 bit, the number of differential amplifiers and comparators must be increased by a factor of 2, which has the disadvantage of increasing power consumption and occupied area. is doing.
- the required specifications such as the offset error of the differential amplifier, the amplification factor, the offset error of the comparator, and the comparison accuracy become higher, there are disadvantages. .
- Patent Document 1 discloses an AZD modification that improves the above-described disadvantages.
- FIG. 15 shows an example of the configuration of another conventional parallel AZD conversion 1500 that improves on the disadvantages of the parallel AZD converter as described above.
- the AZD conversion 1500 includes a reference voltage generation circuit 1501, a differential amplifier array 1502, an interpolation resistor array 1503, a comparator array 1504, and an encoding circuit 1505.
- the AZD transformation ⁇ 1500 has the same structure in the comparator array and the encoding circuit, but the reference voltage generation circuit 1501 has a smaller number of resistors, and the differential The difference is that the number of differential amplifiers included in the amplifier array 1502 is small, and the interpolation resistor array 1503 is provided.
- the reference voltage generation circuit 1501 is configured to reduce the voltage between the high-voltage side reference voltage 1501a and the low-voltage side reference voltage 1501b to less than 2 N (N: number of bits of the AZD converter) m resistors
- the reference voltages VRl to VRm + 1 are generated by dividing by R1 to Rm.
- the reference voltages VR1 to V Rm + 1 are input to the differential amplifier row 1502.
- the differential amplifier array 1502 has m + 1 differential amplifiers, and is parallel to the relationship between the analog input signal voltage input from the analog input signal voltage input terminal AIN and the reference voltages VR1 to VRm + 1. Performs predetermined amplification and inputs to interpolation resistor array 1503.
- the interpolation resistor array 1503 includes a plurality of resistors, and each of the differential voltage between the positive output voltage and the negative output voltage of two adjacent differential amplifiers and the differential voltage between the negative output voltage and the positive output voltage are divided. To obtain a differential interpolated voltage, which is supplied to the comparator array 1504. Comparator string 1504 compares each interpolation voltage in parallel. The encoding circuit 1505 logically processes (converts) the comparison result output from the comparator array 1504 and outputs a digital signal DOUT having a predetermined resolution.
- the AZD conversion 1500 can reduce the number of differential amplifiers to 1 ZL compared to the conventional AZD converter 1400. Therefore, it has the advantage that the power and area can be reduced.
- the comparator As the resolution is increased by 1 bit, the number of comparators increases by a factor of 2 and the current consumption and occupied area increase. is there. Also, in order to increase the resolution of the AZD converter, the required specifications such as the offset error and comparison accuracy of the comparator are disadvantageous, similar to the conventional AZD conversion 1400. is there.
- Patent Document 2 discloses an AZD modification that improves the above-described disadvantages.
- FIG. 16 shows an example of the configuration of another prior art parallel AZD converter 1600 that further improves on the disadvantages of the parallel AZD converter as described above.
- the AZD converter 1600 includes a reference voltage generation circuit 1601, a differential amplifier row 1602, a comparator row 1604, and an encoding circuit 1605.
- the AZD conversion 1600 has the same structure as the reference voltage generation circuit 1601, the differential amplifier array 1602 and the encoding circuit 1605, but includes an interpolation resistor array 1503. The difference is that the input of the comparator array is the positive and negative output voltages of two adjacent differential amplifiers.
- the reference voltage generation circuit 1601 is configured to reduce the voltage between the high-voltage side reference voltage 1601a and the low-voltage side reference voltage 1601b to less than 2 N (N: number of bits of the AZD converter) m resistors
- the reference voltages VRl to VRm + 1 are generated by dividing by R1 to Rm.
- the reference voltages VR1 to V Rm + 1 are input to the differential amplifier row 1602.
- the differential amplifier row 1602 has m + 1 differential amplifiers, and is parallel to the relationship between the analog input signal voltage input from the analog input signal voltage input terminal AIN and the reference voltages VR1 to VRm + 1. Predetermined amplification is applied to the comparator array 1604.
- Each comparator included in the comparator row 1604 is supplied with positive and negative outputs of two differential amplifiers adjacent to each other.
- the input transistors of each comparator are configured with a predetermined size ratio, and compare in parallel while interpolating the positive and negative output of two adjacent differential amplifiers in synchronization with the clock signal CLK. Note that interpolation processing does not require interpolation resistance.
- the encoding circuit 1605 logically processes (converts) the comparison result output from the comparator array 1604 and outputs a digital signal DOUT having a predetermined resolution.
- FIG. 17 shows an example of the configuration of a dynamic comparator 1700 used in the comparator array 1604 that constitutes the parallel AZD converter 1600 shown in FIG.
- Comparator 1700 is composed of an input transistor unit including NMOS transistors ml 1, ml2, m21, and m22, and an NMOS transistor.
- Positive feedback part cross-coupled inverter latch part
- transistors mla and mlb and PMOS transistors m3a and m3b including transistors mla and m3b.
- Output terminal QB force to the gate terminal of NMOS transistor mla and m3a in the positive feedback part and the drain terminal of PMOSm3b
- the output terminal Q is connected to the gate terminals of the transistors mlb and m3b in the positive feedback section and the drain terminal of the PMOS transistor m3a.
- an NMOS transistor m2a that acts as a switch in synchronization with the clock signal CLK is connected between the drain terminal of the NMOS transistor mla and the drain terminal of the PMOS transistor m3a.
- the drain terminal of the NMOS transistor mlb and the PMOS transistor m3b An NMOS transistor m2b that functions as a switch in synchronization with CLK is connected between the drain terminal of the first and second drain terminals.
- the source terminals of the PMOS transistors m3a and m3b are connected to the power supply VDD.
- a PMOS transistor m4a which acts as a switch in synchronization with the clock signal CLK, is connected between the drain terminal of the PMOS transistor m3a and the power supply VDD, and between the drain terminal of the PMOS transistor m3b and the power supply VDD, CLK
- a PMOS transistor m4b which acts as a switch in synchronization with is connected.
- the gate terminals of the NMOS transistors mil, m21, ml2, and m22 that constitute the input transistor unit are the positive output Vol, the negative output Vobl, and the second differential amplifier of the first differential amplifier, respectively.
- the positive output Vo2 and the negative output Vob2 are connected, the source terminal is connected to the reference ground potential VSS, the drain terminals of the NMOS transistors mil and ml2 are the source terminals of the NMOS transistor mla (hereinafter referred to as node Va),
- the drain terminals of the NMOS transistors m21 and m22 are connected to the source terminal (hereinafter referred to as node Vb) of the NMOS transistor mlb.
- Gate terminals of NMOS transistors m2a and m2b acting as switches in synchronization with the clock signal CLK and gate terminals of PMOS transistors m4a and m4b acting as switches in synchronization with the clock signal CLK are both connected to the clock signal CLK It has been.
- the input transistor unit determines a threshold voltage Vtn by performing a predetermined weighting operation, and a difference voltage between the positive output voltage Vol and the negative output voltage Vobl of the first differential amplifier, and a second differential amplifier The comparison result of comparing the difference voltage between the positive output voltage Vo2 and the negative output voltage Vob2 is output to the positive feedback section.
- the predetermined weighting operation is, for example, an input transistor This is realized by setting the size ratio of the gate widths w of the transistors at a certain value.
- a threshold voltage Vtn is obtained.
- the positive feedback unit when the clock signal CLK is equal to or higher than a predetermined level (hereinafter referred to as “High”), the PMOS transistors m4a and m4b are opened (OFF), and the NMOS transistors m2a and m2b It becomes conductive (ON), amplifies the comparison result output from the input transistor section, holds the amplified comparison result, and outputs the amplified comparison result as a digital signal.
- a predetermined level hereinafter referred to as “High”
- the PMOS transistors m4a and m4b are turned on and the output terminals Q and QB are at the power supply voltage VDD, that is, "High” Will be reset to Also, the NMOS transistors m2a and m2b are in an open state (OFF), the current path is cut off, and the power consumption becomes zero.
- the transistors included in the input transistor portion of the comparator have an arbitrary size ratio (weighting), thereby eliminating the advantage that the interpolation resistor array used in the prior art becomes unnecessary. Have. This also has the advantage that the operating current and area required for the interpolation circuit can be reduced, saving power and saving area. Furthermore, since it is a dynamic comparator, it has the advantage of saving power.
- Patent Document 1 Japanese Patent Laid-Open No. 4-43718
- Patent Document 2 Japanese Patent Laid-Open No. 2003-158456
- the clock signal CLK repeats “Low” and “High” in a certain cycle or indefinite cycle, while the positive output voltage Vol, the negative output voltage Vobl, and the first differential amplifier of the first differential amplifier.
- the positive output voltage Vo2 and negative output voltage Vob2 of the differential amplifier 2 This is a result of outputting a predetermined signal amplification according to the voltage and the reference voltage applied to each differential amplifier. According to this, when Vol-Vobl> 0, Vo2-Vob2> 0, the threshold voltage Vtn is determined by performing a predetermined weighting operation on the input transistor after the clock signal CLK power becomes "High".
- the threshold voltage Vtn is determined by performing a predetermined weighting operation in the input transistor after the clock signal CLK becomes "High”
- Vth shown in FIG. 18 is a threshold voltage of the NMOS transistors ml1, ml2, m21, and m22 in the input transistor section of the comparator.
- the node Va becomes “Low”.
- the NMOS transistors m21 and m22 are both OFF, and further, the NMOS transistors m2a and m2b are OFF.
- the node Vb is in a high impedance state, the charge accumulated in the parasitic capacitance of the node Vb is retained, and the node Vb is not reset to the ground voltage VSS and remains at a high voltage.
- the NMOS transistor m2a is turned off at the node Va, and the current flowing through the node Va becomes almost zero. Also, if ⁇ 0 1> ⁇ 1; 11 and ⁇ 02> ⁇ 1; 11, the NMOS transistor mi l, ml 2 is turned on, so the node Va becomes “Low”. [0024] In the case of VoKVth and Vo2 ⁇ Vth, similarly, even if the series of comparison operations of the comparator is completed with the clock signal CLK power "High", the node Va is not reset to the ground voltage VSS and is high. Keep voltage. Even when the clock signal CLK becomes “Low”, the node Va is not reset to the ground voltage VSS and maintains a high voltage.
- the voltage of the node Vb or Va is not reset even when the clock signal CLK power becomes “Low”, and maintains a high voltage.
- the node Vb or Va that had maintained a high voltage at the moment when the clock signal CLK became “High” must quickly return to the steady state.
- the positive and negative outputs Vol, Vobl, Vo2, and Vob2 of the first and second differential amplifiers naturally increase in frequency, and the node Vb or Va may return to a steady state. This becomes an offset of the comparator, which deteriorates the comparison accuracy of the comparator, and eventually causes a problem that the accuracy of the AZD converter is extremely deteriorated.
- the present invention has been made in view of the strong point, and the object of the present invention is that the frequency of the clock signal CLK and the frequency of the analog input signal are faster than those of the dynamic comparator. Even in this case, the node Vb or Va is forcibly returned to a steady state to improve the comparison accuracy of the comparator.
- the comparator of the present invention is a comparator that receives a plurality of differential voltage pairs and performs a comparison operation for each differential voltage of the plurality of differential voltage pairs in synchronization with a clock signal. And Each of the plurality of differential voltage pairs is input by inputting the plurality of differential voltage pairs and performing a voltage-current conversion operation by performing a predetermined weighting operation on the plurality of differential voltage pairs. A differential comparison operation is performed on the differential voltage of the input transistor, and the differential comparison result is received from the input transistor unit that outputs the differential current pair as a result of the differential comparison, and is synchronized with the clock signal.
- a positive feedback unit that amplifies the received differential comparison result to a predetermined voltage level and outputs it as a comparison result of the comparator, and the clock signal is at the predetermined level. If not, a reset unit is provided that resets both of the two connection units connecting the input transistor unit and the positive feedback unit to a predetermined reset voltage.
- the present invention is characterized in that, in the comparator, the predetermined reset voltage reset by the reset unit is a ground voltage.
- the present invention provides the comparator, wherein the reset unit includes a reset voltage generator that generates the predetermined reset voltage, and the reset voltage generator includes the input transistor unit and the positive feedback unit.
- a replica circuit including at least one circuit portion of a differential pair of the same circuit as the circuit to be connected, and a voltage at a connection portion between the input transistor portion and the positive feedback portion of the replica circuit is set to the predetermined reset voltage.
- the comparator of the present invention is a comparator that receives a plurality of differential voltage pairs and performs a comparison operation on each differential voltage of the plurality of differential voltage pairs in synchronization with a clock signal. Differential voltage pairs are input, and a voltage-current conversion operation is performed by performing a predetermined weighting operation on the plurality of differential voltage pairs, whereby the differential voltage of each of the plurality of differential voltage pairs subjected to the weighting is calculated. The differential comparison operation is performed! The differential comparison result of the differential transistor is output, and the differential comparison result of the input transistor unit is received and synchronized with the clock signal.
- the comparator of the present invention is a comparator that receives a plurality of differential voltage pairs and performs a comparison operation for each differential voltage of the plurality of differential voltage pairs in synchronization with a clock signal.
- Differential voltage pairs are input, and a voltage-current conversion operation is performed by performing a predetermined weighting operation on the plurality of differential voltage pairs, whereby the differential voltage of each of the plurality of differential voltage pairs subjected to the weighting is calculated.
- the differential comparison operation is performed.
- the differential transistor has an input transistor unit that outputs a differential current pair as a result of the differential comparison, and a pair of feedback transistors.
- a positive feedback unit that receives a comparison result and amplifies the received differential comparison result to a predetermined voltage level and outputs it as a comparison result of the comparator when the clock signal is at a predetermined level in synchronization with the clock signal
- a pair of feedback of the positive feedback section A pair of switch transistors that are connected in series to the feedback transistors and perform the switching operation by the clock signal to enable or prohibit the operation of the positive feedback section, and when the clock signal is at the predetermined level, And a reset unit that resets both of the two connection units that connect the pair of feedback transistors of the positive feedback unit and the pair of switch transistors to a predetermined reset voltage.
- the present invention is characterized in that, in the comparator, the predetermined reset voltage reset by the reset unit is a ground voltage.
- the reset unit includes a reset voltage generator that generates the predetermined reset voltage
- the reset voltage generator includes the input transistor unit, the positive feedback unit, and the 1 A replica circuit including at least one circuit portion of the differential pair of the same circuit as the circuit configured by the pair of switch transistors, and including the feedback transistor and the switch transistor of the positive feedback section of the replica circuit.
- the voltage of the connected part is output as a predetermined reset voltage.
- the present invention is a comparator that receives a plurality of differential voltage pairs and performs a comparison operation for each differential voltage of the plurality of differential voltage pairs in synchronization with a clock signal.
- a dynamic voltage pair is input, a predetermined weighting operation is performed on the plurality of differential voltage pairs, and a voltage-current conversion operation is performed, so that a difference is obtained for each differential voltage of the plurality of differential voltage pairs that have been weighted.
- An input transistor section that performs a dynamic comparison operation and outputs a differential current pair as a result of the differential comparison, and a pair of feedback transistors, and the input transistor section
- the received differential comparison result is amplified to a predetermined voltage level and output as a comparison result of the comparator.
- a pair of switch transistors that are connected in series to a pair of feedback transistors of the positive feedback section, and that allow or prohibit the operation of the positive feedback section by performing a switch operation according to the clock signal.
- the reset unit is provided with an inverted signal of a clock signal supplied to the positive feedback unit, and a delay that delays the inverted signal of the clock signal supplied to the reset unit for a set time A circuit is provided.
- AZD conversion according to the present invention is characterized in that AZD conversion is performed using the comparator.
- both the nodes are reset. This forcibly resets to a common reset voltage, eliminating the offset and improving the comparison accuracy of the comparator.
- FIG. 1 is a diagram showing a specific configuration of the comparator according to the first embodiment.
- FIG. 2 is a timing chart of the comparator.
- FIG. 3 is a diagram showing the relationship between the input signal trajectory and the comparator threshold voltage in the comparator.
- FIG. 4 is a diagram showing a specific configuration of the comparator of the second embodiment.
- FIG. 5 is a diagram showing a specific configuration of the comparator of the third embodiment.
- FIG. 6 is a diagram showing a specific configuration of the Vreset generator in the comparator of the fourth embodiment. is there.
- FIG. 7 is a diagram showing a specific configuration of the comparator of the fifth embodiment.
- FIG. 8 is a diagram showing a specific configuration of the comparator of the sixth embodiment.
- FIG. 9 is a diagram showing a specific configuration of the comparator of the seventh embodiment.
- FIG. 10 is a diagram showing a specific configuration of a Vreset generator in the comparator of the eighth embodiment.
- FIG. 11 is a diagram showing a specific configuration of an inversion clock generation circuit in the comparator according to the ninth embodiment.
- FIG. 12 is a view showing a timing chart of a comparator using the same inversion clock generation circuit.
- FIG. 13 is a diagram showing a configuration of the AZD converter of the tenth embodiment.
- FIG. 14 is a diagram showing a configuration of a conventional parallel AZD converter.
- FIG. 15 is a diagram showing a configuration of a conventional improved parallel AZD converter.
- FIG. 16 is a diagram showing a configuration of a conventional parallel AZD converter that is further improved.
- FIG. 17 is a diagram showing a configuration of a comparator used in the conventional parallel AZD converter.
- FIG. 18 is a view showing a timing chart of the conventional comparator.
- FIG. 1 is a diagram showing an example of the configuration of the dynamic comparator 100 according to the first embodiment.
- a comparator 100 includes an input transistor unit 10 including NMOS transistors ml 1, ml2, m21, and m22, and a positive feedback unit (cross-coupled unit) including NMOS transistors mla and mlb and PMOS transistors m3a and m3b.
- an NMOS transistor m2a acting as a switch in synchronization with the clock signal CLK is connected between the drain terminal of the NMOS transistor mla and the drain terminal of the PMOS transistor m 3a, and the NMOS transistor mlb
- An NMOS transistor m2b that acts as a switch in synchronization with CLK is connected between the drain terminal of the PMOS transistor and the drain terminal of the PMOS transistor m3b.
- the source terminals of the PMOS transistors m3a and m3b are connected to the power supply VDD.
- a PMOS transistor that acts as a switch in synchronization with the clock signal CLK between the drain terminal of the PMOS transistor m3a and the power supply VDD.
- a transistor m4a is connected, and a PMOS transistor m4b acting as a switch in synchronization with the clock signal CLK is connected between the drain terminal of the PMOS transistor m3b and the power supply VDD.
- the gate terminals of the NMOS transistors ml 1, m21, ml2 and m22 constituting the input transistor unit 10 are respectively positive output Vol, negative output Vobl of the first differential amplifier, positive output Vo2 of the second differential amplifier, The negative output Vob2 is connected, the source terminal is connected to the reference ground potential VSS, the drain terminals of the NMOS transistors mil and ml2 are the source terminal (node Va) of the NMOS transistor mla, and the drain terminals of the NMOS transistors m21 and m22 are The NMOS transistor mlb is connected to the source terminal (node Vb).
- NMOS switch transistors m2a and m2b that act as switches in synchronization with the clock signal CLK and gate terminals of NMOS switch transistors m4a and m4b that act as switches in synchronization with the clock signal CLK are connected to the clock signal CLK It has been. Further, an NMOS transistor mm that acts as a reset transistor is connected between the node Va and the reset voltage input terminal Vreset, and an NMOS transistor that acts as a reset transistor between the node Vb and the reset voltage input terminal V reset. mrb is connected.
- These reset transistors mra and mrb constitute a reset unit 12, and an inverted signal ZCLK of the clock signal is connected to the gate terminals of these reset transistors mra and mrb.
- the above is the configuration of the dynamic comparator 100 according to the first embodiment.
- FIG. 2 shows a clock signal CLK, output terminals Q and QB of the comparator 100, positive output Vol and negative output Vobl of the first differential amplifier, positive output Vo2 and negative output Vob2 of the second differential amplifier. Show the timing chart of the voltage at node Va and Vb of comparator 100! /
- This action is less than the threshold voltage Vth of the input transistor unit 10 for both the positive outputs Vol and Vo2 of the first and second differential amplifiers, or for both the negative outputs Vobl and Vob2 of the first and second differential amplifiers, It is effective even if both NMOS transistors ml 1 and ml2 in input transistor section 10 or NMOS transistors m21 and m22 force S are turned OFF, so the voltages of nodes Va and Vb are reset to the predetermined reset voltage Vreset. (Reset state).
- the NMOS transistors m2a and m2b are turned on, and the PMOS transistors m4a and m4b are turned off. As a result, the positive feedback section 11 becomes operable.
- the NMOS transistors mil, ml2, m21, and m22 of the input transistor unit 10 determine the threshold voltage Vtn by performing a predetermined weighting operation, and the positive output voltage Vol and the negative output voltage Vobl of the first differential amplifier Is compared with the difference voltage between the positive output voltage Vo2 and the negative output voltage Vob2 of the second differential amplifier.
- the differential current pair flowing in Vb is output to the positive feedback section 11.
- the predetermined weighting calculation is realized, for example, by setting the size ratio of the gate width W of the transistors of the input transistor unit 10 to a constant value.
- the threshold voltage Vtn can be obtained by setting the size ratio of the gate width W of the transistors mi 1 and ml 2 and the size ratio of the gate width W of the transistors ml 2 and m 22 to 1: 3, respectively.
- any method can be used as a method for realizing the predetermined weighting calculation described above. For example, the same effect can be obtained even if the predetermined weighting calculation described above is realized by setting the ratio of the gate length L of the gate width W of the transistor of the input transistor unit 10 equal to a constant value. be able to.
- the gate weight W and gate length L of the transistors of the input transistor section 10 are set to a constant value by setting the ratio of the number of transistors connected in parallel to be equal to each other, thereby realizing the predetermined weighting calculation described above.
- the same effect can be obtained.
- the drain currents of the NMOS transistors mi 1, ml 2, m 21, and m 22 of the input transistor unit 10 vary depending on the respective gate terminal voltages.
- the drain voltage VDS1 according to the gate terminal voltage of the transistors mil and ml2, and the transistor m2
- a drain voltage VDS2 corresponding to the gate terminal voltage of 1 and m22 is generated, and the positive feedback unit 1 1 positively feeds back the differential voltage of these drain voltages VDS1 and VDS2 to supply voltage VDD that is a predetermined voltage level, that is, Amplifies to "High” or the reference ground voltage VSS, that is, “Low”, and maintains that state (Compare & Latch state).
- the NMOS transistors mi1, ml2, m21, and m22 of the input transistor section 10 operate in the linear region at the moment when the clock signal CLK becomes "High".
- the gate length L of transistors ml l, ml2, m21, and m22 is constant, the gate widths are Wl, W2, Wl, and W2, respectively, the threshold voltage is Vth, the carrier mobility is zn, and the gate capacitance is Cox
- the threshold voltage of the comparator 100 shown in FIG. 1 is a state where the positive feedback unit 11 becomes insensitive
- drain conductances G11 and G12 of the transistors mi l and ml2 Is obtained when the sum of the drain conductances G21 and G22 of the transistors m21 and m22 is equal.
- Wl -Vol + W2-Vo2 Wl -Vobl + W2-Vob2
- the size ratio between the gate widths Wl and W2 is expressed as follows:
- FIG. Figure 3 shows the locus and threshold of the input signal of comparator 100, that is, the positive output voltage Vol and negative output voltage Vobl of the first differential amplifier, and the positive output voltage Vo2 and negative output voltage Vob2 of the second differential amplifier.
- FIG. The broken line A in Fig. 3 represents the locus on the left side of Equation (1.7), and Vol and Vo2 are divided into n: m ⁇ n.
- broken line B represents the locus on the right side of equation (1.7), and Vobl and Vob2 are divided into n: m ⁇ n.
- the intersection Vtn between the broken line A and the broken line B indicates the threshold voltage of the comparator 100.
- the intersection Vtn divides the intersection Vtl of Vol and Vobl and the intersection Vt2 of Vo2 and Vob2 into n: mn. Therefore, by setting the gate size ratio of the NMOS transistor (mil, m21) and (ml2, m22) of the input transistor 10 to nZm: (m ⁇ n) Zm, the distance between the intersection Vtl and the intersection Vt2 m divided and its The threshold voltage Vtn with the position n can be obtained.
- the dynamic comparator 100 uses the reset transistors mra and mrb that operate in synchronization with the inverted signal of the clock signal in the reset state, to obtain the nodes Va and Vb. Since it has a function of resetting to the predetermined reset voltage Vreset, it is possible to ensure a good comparison accuracy even when the clock signal frequency and analog input signal frequency are increased.
- FIG. 4 is a diagram illustrating an example of the configuration of the dynamic comparator 400 of the first embodiment.
- the comparator 400 includes an input transistor unit including NMOS transistors mi1, ml2, m21, and m22, and a positive feedback unit (cross-coupled inverter latch unit) including NMOS transistors mla and mlb and PMOS transistors m3a and m3b.
- the output terminal QB is connected to the gate terminals of the transistors mlb and m3b of the positive feedback section and the drain terminal of the transistor m3a.
- the output terminal Q is connected to the gate terminals of the transistors mla and m3a of the positive feedback section and the drain terminal of the transistor m3b.
- An NMOS transistor m2a that acts as a switch in synchronization with the clock signal CLK is connected between the drain terminal of the NMOS transistor mla and the drain terminal of the PMOS transistor m3a, and the drain terminal of the NMOS transistor mlb and the PMOS transistor m3b
- An NMOS transistor m2b that acts as a switch in synchronization with CLK is connected between the drain terminal and the drain terminal.
- the source terminals of the PMOS transistors m3a and m3b are connected to the power supply VDD.
- a PMOS transistor m4a which acts as a switch in synchronization with the clock signal CLK, is connected between the drain terminal of the PMOS transistor m3a and the power supply VDD, and C LK is connected between the drain terminal of the PMOS transistor m3b and the power supply VDD.
- a PMOS transistor m4b which acts as a switch in synchronization with, is connected.
- the gate terminals of the NMOS transistors mi, m21, ml2, and m22 that make up the input transistor section are the positive output Vol, negative output Vobl of the first differential amplifier, and the positive output of the second differential amplifier, respectively.
- Vo2 and negative output Vob2 are connected, the source terminal is connected to the reference ground potential VSS, the drain terminals of transistors mil and ml2 are the source terminal (node Va) of transistor mla, and the drain terminals of transistors m21 and m22 are Transistor mlb so Connected to the source terminal (Vb)!
- NMOS transistors m2a and m2b that function as switches in synchronization with the clock signal CLK and the gate terminals of PMOS transistors m4a and m4b that function as switches in synchronization with the clock signal CLK Connected to CLK.
- an NMOS transistor mm acting as a reset transistor is connected between the node Va and the ground voltage VSS
- an NMOS transistor mrb acting as a reset transistor is connected between the Vb and the ground voltage VSS.
- An inverted signal ZCLK of the clock signal is connected to the gate terminals of the NMOS transistors mra and mrb that operate.
- a series of operations of the dynamic comparator 400 of the second embodiment is basically almost the same as a series of operations of the dynamic comparator 100 of the first embodiment. The difference is the reset state when the following clock signal CLK is "Low".
- the NMOS transistors m2a and m2b are turned on, and the PMOS transistors m4a and m4b are turned off.
- the positive feedback section becomes operable.
- the NMOS transistors mil, ml2, m21, and m22 in the input transistor section determine the threshold voltage Vtn by performing a predetermined weighting operation, and the difference between the positive output voltage Vol and the negative output voltage Vobl of the first differential amplifier Voltage, positive output voltage Vo2 of the second differential amplifier and negative output voltage
- the comparison result compared with the voltage difference from the voltage Vob2 is output to the positive feedback section.
- the drain current of each of the transistors mi l, ml 2, m21, and m22 in the input transistor section varies depending on the gate terminal voltage thereof.
- the drain voltage VDS1 corresponding to the gate terminal voltage of the transistors mil and ml2 and the drain voltage VDS2 corresponding to the gate terminal voltage of the transistors m21 and m22 are generated, and the positive feedback section is set to VDS1 and VDS2.
- the differential voltage is positively fed back and amplified to the power supply voltage VDD, that is, “High” or the reference ground voltage VSS, that is, “Low”, and this state is maintained (Compare & Latch state).
- the current flows through this circuit. Does not flow.
- VD S1> VDS2 by positively feeding back the differential voltage, the output terminal Q of the comparator is amplified to “High” and the output terminal QB is amplified to “Low”.
- the inverted signal / CLK of the clock signal becomes “Low”, the NMOS transistors mra and mrb are turned OFF, and the nodes Va and Vb and the reference ground voltage VSS are disconnected.
- the dynamic comparator 400 of the second embodiment resets the nodes Va and Vb to the ground voltage VSS using the switch operating in synchronization with the inverted signal of the clock signal in the reset state.
- the difference is that the reset voltage input terminal Vreset is not required, and the node Va and Vb voltages in the reset state are not the Vreset but the ground voltage VSS.
- FIG. 5 is a diagram illustrating an example of the configuration of the dynamic comparator 500 of the third embodiment.
- the comparator 500 includes an input transistor unit including NMOS transistors mi1, ml2, m21, and m22, and a positive feedback unit (cross-coupled inverter latch unit) including NMOS transistors mla and mlb and PMOS transistors m3a and m3b.
- Positive feedback transistor mla, m3a The output terminal Q is connected to the gate terminal of the transistor m3b and the drain terminal of the transistor m3b.
- the output terminal QB is connected to the transistors mlb and m3b of the positive feedback section and the drain terminal of the transistor m3a.
- An NMOS transistor m2a that acts as a switch in synchronization with the clock signal CLK is connected between the drain terminal of the NMOS transistor mla and the drain terminal of the PMOS transistor m3a, and the drain terminal of the NMOS transistor mlb and the PMOS transistor m3b
- An NMOS transistor m2b that acts as a switch in synchronization with CLK is connected between the drain terminal and the drain terminal.
- the source terminals of the PMOS transistors m3a and m3b are connected to the power supply VDD.
- a PMOS transistor m4a which acts as a switch in synchronization with the clock signal CLK, is connected between the drain terminal of the PMOS transistor m3a and the power supply VDD, and C LK is connected between the drain terminal of the PMOS transistor m3b and the power supply VDD.
- a PMOS transistor m4b which acts as a switch in synchronization with, is connected.
- the gate terminals of the NMOS transistors mi, m21, ml2, and m22 that make up the input transistor section are the positive output Vol, negative output Vobl of the first differential amplifier, and the positive output of the second differential amplifier, respectively.
- Vo2 and negative output Vob2 are connected, the source terminal is connected to the reference ground potential VSS, the drain terminals of transistors mil and ml2 are the source terminal (node Va) of mla, and the drain terminals of transistors m21 and m22 are transistors Connected to the mlb source terminal (V b).
- the gate terminals of the NMOS transistors m2a and m2b that function as switches in synchronization with the clock signal CLK and the gate terminals of the PMOS transistors m4a and m4b that function as switches in synchronization with the clock signal CLK are connected to the clock signal CLK. ing.
- an NMOS transistor mr acting as a reset transistor is connected between the two nodes (connection portions) Va and Vb, and the inversion of the clock signal is connected to the gate terminal of the NMOS transistor mr acting as the reset transistor.
- Signal ZCLK is connected to V.
- a series of operations of the dynamic comparator 500 of the third embodiment is basically equal to a series of operations of the dynamic comparator 100 of the first embodiment. The difference is the reset state when the following clock signal CLK is "Low”.
- the clock signal CLK is "Low”
- the NMOS transistors m2a and m2b are turned off and the PMOS transistors m4a and m4b are turned on.
- the positive feedback section does not operate and the output terminals Q and QB are pulled up to "High”.
- the transistors m2a and m2b are OFF, no current flows in this circuit.
- the inverted signal ZCLK of the clock signal becomes “High”, the NMOS transistor mr is turned on, and the two nodes Va and Vb are short-circuited and made conductive.
- This effect is effective even if both Vol and Vo2 or Vobl and Vob2 are both below the threshold voltage Vth of the input transistor section and both the NMOS transistors mil and ml2 of the input transistor section or both the transistors m21 and m22 are turned off. Therefore, the voltages of nodes Va and Vb are reset to the same potential. Assuming that no current flows in this circuit and at least one of the transistors mil, ml2, m21, and m22 is ON, after all, the nodes Va and Vb are reset to the ground voltage VSS ( Reset state).
- the NMOS transistors m2a and m2b are turned on, and the PMOS transistors m4a and m4b are turned off.
- the NMOS transistors mil, ml2, m21, and m22 in the input transistor section determine the threshold voltage Vtn by performing a predetermined weighting operation, and the difference between the positive output voltage Vol and the negative output voltage Vobl of the first differential amplifier
- the comparison result of the comparison between the voltage and the difference voltage between the positive output voltage Vo2 and the negative output voltage Vob2 of the second differential amplifier is output to the positive feedback section. Since the implementation of the predetermined weighting calculation has already been described, it will be omitted.
- the drain currents of the transistors m 11, ml 2, m 21, and m 22 in the input transistor section vary depending on their gate terminal voltages.
- a drain voltage VDS1 corresponding to the gate terminal voltage of the transistors mil and ml2 and a drain voltage VDS2 corresponding to the gate terminal voltage of the transistors m21 and m22 are generated, and the positive feedback section is the difference between VDS1 and VDS2.
- the voltage is positively fed back and amplified to the power supply voltage V DD or “High” or the reference ground voltage VSS or “Low”, and this state is maintained (Compare & Latch state). At this time, during the period when the output terminals Q and QB of the comparator are transitioning, the current flows through the circuit.
- the dynamic comparator 500 has a function of resetting the nodes Va and Vb to the same potential using the switch that operates in synchronization with the inverted signal of the clock signal in the reset state. Therefore, it is possible to reduce the deterioration of the comparison accuracy, which was a problem in the prior art, which occurred when the clock signal frequency and the analog input signal frequency became faster.
- the reset voltage input terminal Vreset is not required, and the reset node Va and Vb voltages are not Vreset, but the nodes Va and Vb are at the same potential or in the reset state, and the transistor ml If any of l, ml2, m21, and m22 is ON, the node Va and Vb voltages are different from the ground voltage VSS. Further, it is different from the comparator 400 in that it can be configured even if the number of reset transistors is one less.
- FIG. 6 is a diagram illustrating an example of a configuration of a Vreset generator (reset voltage generator) 600 according to the fourth embodiment, which relates to the dynamic comparator 100 according to the first embodiment.
- the Vreset generator 600 is a half circuit of the comparator 100 and is configured as a replica circuit of the comparator 100.
- the drain terminal is connected.
- an NMOS transistor m2 acting as a switch is connected between the drain terminal of the NMOS transistor ml and the drain terminal of the PMOS transistor m3 in synchronization with the Vreset generator operation signal ENABLE.
- the source terminal of the PMOS transistor m3 is connected to the power supply VDD.
- a PMOS transistor m4 that functions as a switch is connected between the drain terminal of the PMOS transistor m3 and the power supply VDD in synchronization with the Vreset generator operation signal ENABLE.
- the gate terminals of the NMOS transistors mi l and m21 constituting the input transistor section are connected to the common mode voltage Vomid of the positive output and the negative output of the differential amplifier, the reference terminal is connected to the reference ground voltage VSS, and the input transistor is connected to the input transistor.
- the voltage at the connection point between the data unit 10 and the positive feedback unit 11, that is, the connection between the drain terminal of the NMOS transistors ml and ml2 and the source terminal of the feedback transistor ml is output externally as a reset voltage Vreset. .
- Vreset generator operation signal The gate terminal of the NMOS transistor m2 that acts as a switch in synchronization with ENABLE and the gate terminal of the PMOS transistor m4 that acts as a switch in synchronization with the Vreset generator operation signal ENAB LE Connected to signal ENABLE.
- the above is an example of the configuration of the Vreset generator 600 according to the fourth embodiment, which relates to the dynamic comparator 100 according to the first embodiment.
- Vreset generator 600 Next, a series of operations of the Vreset generator 600 according to the fourth embodiment will be described with reference to FIG.
- the NMOS transistor m2 When the Vreset generator operation signal ENABLE is “High”, the NMOS transistor m2 is turned on and the PMOS transistor m4 is turned off. As a result, the half circuit of the positive feedback section of the comparator 100 becomes operable.
- the NMOS transistors ml1 and ml2 in the input transistor section have a predetermined size ratio.
- the size ratio of the gate width W between the transistor mi 1 and the transistor ml 2 is (mZ2) Zm: (mZ2) Zm in the expression (1.6).
- any method can be used as a method for realizing the predetermined size ratio.
- the voltage between the gate terminal and the source terminal of the transistor mi l and the transistor ml 2 is Vomid, and according to Vomid, a certain drain current is caused to flow through the circuit to the transistors mi l and ml 2.
- the combined drain current of the transistors mi l and ml 2 flows through the transistors m3, m2 and ml.
- This is the Vreset generator operating current. Since the transistor m3 has a diode connection in which the gate terminal and the drain terminal are connected, it operates as a resistor having a certain conductance. Therefore, a certain voltage is applied to the gate terminal of the transistor m3 by the Vreset generator operating current. In other words, it occurs at the drain terminal of transistor m3.
- the gate terminal voltage of transistor m2 Is the Vreset generator operating signal ENABLE
- the drain terminal voltage of transistor m2 is the drain terminal voltage of transistor m3
- Vreset generator operating current gate terminal source-terminal voltage (ENABLE—m2 source terminal voltage)
- drain terminal A certain voltage is generated in the source terminal voltage of the transistor m2 that satisfies the relationship of the source terminal voltage (the drain terminal voltage of the transistor m3 and the source terminal voltage of the transistor m2).
- the gate terminal voltage of the transistor ml is the drain terminal voltage of the transistor m3
- the drain terminal voltage of the transistor ml is the source terminal voltage of the transistor m2
- the Vreset generator operating current the gate terminal source voltage (transistor m3 drain terminal voltage Transistor ml source terminal voltage), drain terminal Source terminal voltage (transistor m2 source terminal voltage Transistor ml source terminal voltage) Occurs. That is, the source terminal voltage of the transistor ml is generated as the reset voltage Vreset.
- the nodes Va and Vb are set when the comparator 100 is in the reset state.
- the comparator 100 By resetting as the reset voltage Vreset generated by the Vreset generator 600 of the fourth embodiment, when the clock signal CLK transits from “Low” to “High”, that is, the comparator 100 also enters the Compara & Latch state. At the time of transition, the comparator 100 operates most sensitively because the potentials of the nodes Va and Vb are controlled in a steady state.
- the Vreset generator 600 according to the fourth embodiment which is related to the dynamic comparator 100 according to the first embodiment, has the half circuit of the comparator 100 as a replica circuit, and is reset by the above-described operation. By generating the voltage Vreset, the dynamic comparator 100 of the first embodiment can be operated most efficiently and quickly.
- the Vreset generator 600 shown in FIG. 6 is composed of only the circuit portion constituting one of the differential pairs in the configuration of the comparator 100 shown in FIG. Of course, it may be configured. In this case, the output terminal Q and the inverting output terminal QB are short-circuited, and the connection point between the feedback transistor mla and the transistor ml2 in the input transistor section is returned. Connect the return transistor mlb and the connection point of the transistor m21 in the input transistor section, and connect two nodes Va ⁇ Vb.
- the NMOS transistor and the PMOS transistor are interchanged in this configuration together with the force comparator in which the input transistor unit is an NMOS transistor, and the input transistor unit is also a PMOS transistor. A similar effect can be obtained.
- FIG. 7 is a diagram illustrating an example of the configuration of the dynamic comparator 700 according to the fifth embodiment.
- the comparator 700 includes an input transistor unit including NMOS transistors mi1, ml2, m21, and m22, and a positive feedback unit including a pair of feedback transistors mla and mlb including NMOS transistors and a pair of PMOS transistors m3a and m3b ( Cross-coupled inverter latch section), and the output terminal QB is connected to the gate terminals of the transistors mla and m3a in the positive feedback section and the drain terminal of the transistor m3b, and the gate terminals and transistors m3a of the transistors mlb and m3b in the positive feedback section Output terminal Q is connected to the drain terminal.
- a switch transistor m2a composed of an NMOS transistor that operates ONZOFF in synchronization with the clock signal CLK is connected between the drain terminal of the NMOS transistor mla and the drain terminal of the PMOS transistor m3a, and the drain terminal of the NMOS transistor mlb and the PMOS transistor Connected to the drain terminal of m3b is a switch transistor m2b consisting of NMOS transistors that operate ONZOFF in synchronization with the clock signal CLK!
- the source terminals of the PMOS transistors m3a and m3b are connected to the power supply VDD.
- a PMOS transistor m4a acting as a switch is connected between the drain terminal of the PMOS transistor m3a and the power supply VDD in synchronization with the clock signal CLK, and is synchronized with CLK between the drain terminal of the PMOS transistor m3b and the power supply VDD.
- the PMOS transistor m4b acting as a switch is connected.
- the gate terminals of the NMOS transistors ml1, m21, ml2, and m22 that make up the input transistor section are the positive output Vol and negative output Vobl of the first differential amplifier, and the positive output Vo2 and negative of the second differential amplifier, respectively.
- the output Vob2 is connected, the source terminal is connected to the reference ground voltage VSS, the drain terminals of the transistors mi l and ml 2 are the source terminal (node Va) of the transistor mla, and the drain terminals of the transistors m21 and m22 are the transistors mlb Connected to the source terminal (node Vb).
- the gate terminals of the NMOS transistors m2a and m2b acting as switches and the gate terminals of the PMOS transistors m4a and m4b acting as switches in synchronization with the clock signal CLK are connected to the clock signal CLK.
- a connection portion between the source terminal of the switch transistor m2a and the drain terminal of the feedback transistor mla is a node Vc
- a connection portion between the source terminal of the switch transistor m2b and the drain terminal of the feedback transistor mlb is a node Vd.
- An NMOS transistor mm acting as a reset transistor is connected between the node Vc and the reset voltage input terminal Vreset
- an N MOS transistor mrb acting as a reset transistor is connected between the node Vd and the reset voltage input terminal Vreset
- the inverted signal ZCLK of the clock signal is connected to the gate terminals of the NMOS transistors mra and mrb that act as reset transistors.
- a series of operations of the dynamic comparator 700 of the fifth embodiment is basically substantially equal to a series of operations of the dynamic comparator 100 of the first embodiment. The difference is the reset state when the following clock signal CLK is "Low".
- the NMOS transistors m2a and m2b are turned on, and the PMOS transistors m4a and m4b are turned off.
- the NMOS transistors mil, ml2, m21, and m22 in the input transistor section determine the threshold voltage Vtn by performing a predetermined weighting operation, and the difference between the positive output voltage Vol and the negative output voltage Vobl of the first differential amplifier
- the comparison result of the comparison between the voltage and the difference voltage between the positive output voltage Vo2 and the negative output voltage Vob2 of the second differential amplifier is output to the positive feedback section. Since the implementation of the predetermined weighting calculation has already been described, it will be omitted.
- the drain currents of the transistors m 11, ml 2, m 21, and m 22 in the input transistor section vary depending on their gate terminal voltages.
- a drain voltage VDS1 corresponding to the gate terminal voltage of the transistors mil and ml2 and a drain voltage VDS2 corresponding to the gate terminal voltage of the transistors m21 and m22 are generated, and the positive feedback section is the difference between VDS1 and VDS2.
- the voltage is positively fed back and amplified to the power supply voltage V DD or “High” or the reference ground voltage VSS or “Low”, and this state is maintained (Compare & Latch state). At this time, during the period when the output terminals Q and QB of the comparator are transitioning, the current flows through the circuit.
- the dynamic comparator 700 uses the switch that operates in synchronization with the inverted signal of the clock signal, and further switches the nodes Vc and Vd to the node Va. And the function to reset Vb to Vreset, it is possible to reduce the deterioration of the comparison accuracy that occurred when the clock signal frequency and analog input signal frequency became faster, which was a problem in the prior art. Become.
- FIG. 8 is a diagram illustrating an example of the configuration of the dynamic comparator 800 of the sixth embodiment.
- the comparator 800 includes an input transistor section including NMOS transistors mi1, ml2, m21, and m22, and a positive feedback section (cross-coupled inverter latch section) including NMOS transistors mla and mlb and PMOS transistors m3a and m3b.
- the output terminal QB is connected to the gate terminals of the transistors mla and m3a in the feedback section and the drain terminal of the transistor m3b.
- the output terminal Q is connected to the gate terminals of the transistors mlb and m3b in the positive feedback section and the drain terminal of the transistor m3a.
- An NMOS transistor m2a that acts as a switch in synchronization with the clock signal CLK is connected between the drain terminal of the NMOS transistor mla and the drain terminal of the PMOS transistor m3a, and the drain terminal of the NMOS transistor mlb and the PMOS transistor m3b
- An NMOS transistor m2b that acts as a switch in synchronization with CLK is connected between the drain terminal and the drain terminal.
- the source terminals of the PMOS transistors m3a and m3b are connected to the power supply VDD.
- a PMOS transistor m4a which acts as a switch in synchronization with the clock signal CLK, is connected between the drain terminal of the PMOS transistor m3a and the power supply VDD, and C LK is connected between the drain terminal of the PMOS transistor m3b and the power supply VDD.
- a PMOS transistor m4b which acts as a switch in synchronization with, is connected.
- the gate terminals of the NMOS transistors mi, m21, ml2, and m22 that make up the input transistor section are the positive output Vol, negative output Vobl of the first differential amplifier, and the positive output of the second differential amplifier, respectively.
- Vo2 and negative output Vob2 are connected, the source terminal is connected to the reference ground voltage VSS, the drain terminals of transistors mil and ml2 are the source terminal (node Va) of transistor mla, and the drain terminals of transistors m21 and m22 are Connected to the source terminal (Vb) of transistor mlb.
- the gate terminals of the NMOS transistors m2a and m2b acting as switches in synchronization with the clock signal CLK and the gate terminals of the PMOS transistors m4a and m4b acting as switches in synchronization with the clock signal CLK are connected to the clock signal CLK.
- a connection point between the source terminal of the transistor m2a and the drain terminal of the transistor mla is a node Vc
- a connection point between the source terminal of the transistor m2b and the drain terminal of the transistor mlb is a node Vd
- NMOS transistor mm acting as a reset transistor is connected to NMOS transistor mrb acting as a reset transistor between Vd and ground voltage VSS
- the gate terminals of NMOS transistors mra and mrb acting as reset transistors are connected to The Inverted signal ZCLK is connected.
- a series of operations of the dynamic comparator 800 of the sixth embodiment is basically almost the same as a series of operations of the dynamic comparator 100 of the first embodiment. The difference is the reset state when the following clock signal CLK is "Low".
- the transistors mla and mlb are turned on, and the nodes Vc and Va and the nodes Vd and Vb are conducted. Accordingly, the voltages of the nodes Va and Vb are also reset to the ground voltage VSS (Reset state).
- the NMOS transistors m2a and m2b are turned on, and the PMOS transistors m4a and m4b are turned off.
- the NMOS transistors mil, ml2, m21, and m22 in the input transistor section determine the threshold voltage Vtn by performing a predetermined weighting operation, and the difference between the positive output voltage Vol and the negative output voltage Vobl of the first differential amplifier
- the comparison result of the comparison between the voltage and the difference voltage between the positive output voltage Vo2 and the negative output voltage Vob2 of the second differential amplifier is output to the positive feedback section. Since the implementation of the predetermined weighting calculation has already been described, it will be omitted.
- Input transistor transistor m The drain currents of 11, ml2, m21, and m22 vary depending on their gate terminal voltages. As a result, a drain voltage VDS1 corresponding to the gate terminal voltage of the transistor mil and the transistor ml2 and a drain voltage VDS2 corresponding to the gate terminal voltage of the transistors m21 and m22 are generated, and the positive feedback section is the difference between VDS1 and VDS2.
- the voltage is positively fed back and amplified to the power supply voltage VDD, that is, “High” or the reference ground voltage VSS, that is, “Low”, and this state is maintained (Compare & Latch state).
- the operation principle of the other circuit is the same as that of the dynamic comparator 100 of the first embodiment.
- the dynamic comparator 800 of the sixth embodiment uses the switch operating in synchronization with the inverted signal of the clock signal in the reset state, and further changes the node Vc and Vd to the node Va. And the function of resetting Vb to the ground voltage VSS can reduce the deterioration of the comparison accuracy that occurred when the clock signal frequency and analog input signal frequency became faster, which was a problem in the prior art. It becomes possible. Also, the comparator 700 is different from the comparator 700 in that the reset voltage input terminal Vreset is not required and the reset node Vc and Vd voltages are not Vreset but the ground voltage VSS.
- FIG. 9 is a diagram illustrating an example of the configuration of the dynamic comparator 900 according to the seventh embodiment.
- the comparator 900 includes an input transistor unit including NMOS transistors mi1, ml2, m21, and m22, and a positive feedback unit (cross-coupled inverter latch unit) including NMOS transistors mla and mlb and PMOS transistors m3a and m3b.
- Output terminal QB force at the gate terminals of the positive feedback transistors mla and m3a and the drain terminal of the transistor m3b
- Output terminal Q at the gate terminals of the positive feedback transistors mlb and m3b and the drain terminal of the transistor m3a Is connected.
- An NMOS transistor m2a that acts as a switch in synchronization with the clock signal CLK is connected between the drain terminal of the NMOS transistor mla and the drain terminal of the PMOS transistor m3a, and the drain terminal of the NMOS transistor mlb and the PMOS transistor m3b
- An NMOS transistor m2b that acts as a switch in synchronization with CLK is connected between the drain terminal and the drain terminal.
- the source terminals of the PMOS transistors m3a and m3b are connected to the power supply VDD.
- a PMOS transistor m4a which acts as a switch in synchronization with the clock signal CLK, is connected between the drain terminal of the PMOS transistor m3a and the power supply VDD, and C LK is connected between the drain terminal of the PMOS transistor m3b and the power supply VDD.
- a PMOS transistor m4b which acts as a switch in synchronization with, is connected.
- the gate terminals of the NMOS transistors mi, m21, ml2, and m22 that make up the input transistor section are the positive output Vol, negative output Vobl of the first differential amplifier, and the positive output of the second differential amplifier, respectively.
- Vo2 and negative output Vob2 are connected, the source terminal is connected to the reference ground voltage VSS, the drain terminals of transistors mil and ml2 are the source terminal (node Va) of transistor mla, and the drain terminals of transistors m21 and m22 are Connected to the source terminal (Vb) of transistor mlb.
- the gate terminals of the NMOS transistors m2a and m2b acting as switches in synchronization with the clock signal CLK and the gate terminals of the PMOS transistors m4a and m4b acting as switches in synchronization with the clock signal CLK are connected to the clock signal CLK.
- connection point between the source terminal of the transistor m2a and the drain terminal of the transistor mla is a node Vc
- the connection point between the source terminal of the transistor m2b and the drain terminal of the transistor mlb is Vd
- the reset transistor is connected between the nodes Vc and Vd.
- An NMOS transistor mr that acts as a reset transistor is connected, and an inverted signal ZCLK of the clock signal is connected to the gate terminal of the NMOS transistor mr that acts as a reset transistor.
- a series of operations of the dynamic comparator 900 of the seventh embodiment is basically equal to a series of operations of the dynamic comparator 100 of the first embodiment. The difference is the reset state when the following clock signal CLK is "Low”.
- the clock signal CLK is “Low”
- the NMOS transistors m2a and m2b are turned off and the PMOS transistors m4a and m4b are turned on.
- the positive feedback section does not operate and the output terminals Q and QB are pulled up to "High”.
- the transistors m2a and m2b are OFF, no current flows in this circuit.
- the inverted signal ZCLK of the clock signal becomes “High”, the NMOS transistor mr is turned on, and the nodes Vc and Vd are conducted. Also, since the output terminals Q and QB are pulled up to "High”, the transistors mla and mlb are turned on, and the nodes Vc and Va are connected, and Vd and Vb are conducted. Therefore, nodes Va and Vb and nodes Vc and Vd are conducted. This effect is effective even when both Vol and Vo2 or Vobl and Vob2 are both below the threshold voltage Vth of the input transistor section and both the NMOS transistors mil and ml2 of the input transistor section or both the transistors m21 and m22 are turned off.
- the voltages of the nodes Vc and Vd are reset to the same potential. Since the output terminals Q and QB are pulled up to "High”, the transistors mla and mlb are turned on, and the nodes Vc and Va and Vd and Vb are conducted. If no current flows in this circuit and at least one of the transistors m11, ml2, m21, and m22 is ON, after all, the nodes Va, Vb, Vc, and Vd are at the ground voltage VSS. Reset (Reset state)
- the NMOS transistors m2a and m2b are turned on, and the PMOS transistors m4a and m4b are turned off.
- the NMOS transistors mil, ml2, m21, and m22 in the input transistor section determine the threshold voltage Vtn by performing a predetermined weighting operation, and the difference between the positive output voltage Vol and the negative output voltage Vobl of the first differential amplifier
- the comparison result of the comparison between the voltage and the difference voltage between the positive output voltage Vo2 and the negative output voltage Vob2 of the second differential amplifier is output to the positive feedback section. Since the implementation of the predetermined weighting calculation has already been described, it will be omitted.
- the drain currents of the transistors m 11, ml 2, m 21, and m 22 in the input transistor section vary depending on their gate terminal voltages.
- a drain voltage VDS1 corresponding to the gate terminal voltage of the transistors mil and ml2 and a drain voltage VDS2 corresponding to the gate terminal voltage of the transistors m21 and m22 are generated, and the positive feedback section is the difference between VDS1 and VDS2.
- the voltage is positively fed back and amplified to the power supply voltage V DD or “High” or the reference ground voltage VSS or “Low” and the state is maintained. Hold (Compare & Latch state). At this time, during the period when the output terminals Q and QB of the comparator are transitioning, the current flows through the circuit.
- the dynamic comparator 900 of the seventh embodiment uses the switch operating in synchronization with the inverted signal of the clock signal in the reset state to share the nodes Va, Vb, Vc, and Vd.
- the switch operating in synchronization with the inverted signal of the clock signal in the reset state uses the switch operating in synchronization with the inverted signal of the clock signal in the reset state to share the nodes Va, Vb, Vc, and Vd.
- the reset voltage input terminal Vreset is not required, and the reset node Vc and Vd voltages are not Vreset but the node Vc and Vd are at the same potential or in the reset state.
- Ml2, m21, and m22 are different in that the voltages of the nodes Va, Vb, Vc, and Vd are the ground voltage V SS if any of them is ON. Also, it differs from the comparator 800 in that it can be configured even if the number of reset transistors is one less.
- FIG. 10 is a diagram illustrating an example of a configuration of a Vreset generator (reset voltage generator) 1000 according to the eighth embodiment, which relates to the dynamic comparator 700 according to the fifth embodiment.
- the Vreset generator 10000 is a half circuit of the comparator 700, and is configured as a replica circuit of the comparator 700.
- the input transistor section including NMOS transistors mi and ml 2 and the NMOS transistor ml and PMOS transistor m3, which are half circuits of the positive feedback section of the comparator 700, are provided.
- the gate terminals of the transistors ml and m3 and the drain of the transistor m3 The terminal is connected.
- an NMOS transistor m2 that acts as a switch in synchronization with the Vreset generator operation signal ENABLE is connected between the drain terminal of the NMOS transistor ml and the drain terminal of the PMOS transistor m3.
- the source terminal of the PMOS transistor m3 is the power supply V Connected to DD.
- a PMOS transistor m4 that acts as a switch is connected between the drain terminal of the PMOS transistor m3 and the power supply VDD in synchronization with the Vreset generator operation signal ENABLE.
- the NMOS transistors m11 and m21 constituting the input transistor section are connected to the common mode voltage Vomid of the positive output and the negative output of the differential amplifier, the source terminal is connected to the reference ground voltage VSS, and the NMOS transistor mi
- the drain terminals of l and ml 2 are connected to the source terminal of the feedback transistor ml, the drain terminal of the feedback transistor ml is connected to the source terminal of the switch transistor m2, and the connection between this feedback transistor ml and the switch transistor m2 Part of the voltage is output externally as the specified reset voltage Vreset.
- the above is an example of the configuration of the Vreset generator 1000 of the eighth embodiment related to the dynamic comparator 700 of the fifth embodiment.
- the NMOS transistor m2 When the Vreset generator operation signal ENABLE is "High", the NMOS transistor m2 is turned on and the PMOS transistor m4 is turned off. As a result, the half circuit of the positive feedback section of the comparator 100 becomes operable.
- the NMOS transistors ml1 and ml2 in the input transistor section have a predetermined size ratio.
- the size ratio of the gate width W between the transistor mi 1 and the transistor ml 2 is (mZ2) Zm: (mZ2) Zm in the expression (1.6).
- any method can be used as a method for realizing the predetermined size ratio.
- the voltage between the gate terminal and source terminal of the transistors mi l and ml 2 The pressure is Vomid.
- Vomid a certain drain current is caused to flow through the circuit through the transistors mi l and ml 2.
- the combined drain current of transistors mi l and ml 2 flows through transistors m3, m2 and ml.
- This is the Vreset generator operating current. Since the transistor m3 has a diode connection in which the gate terminal and the drain terminal are connected, it operates as a resistor having a certain conductance.Therefore, a certain voltage is generated by the Vreset generator operating current. It occurs at the drain terminal of the star m3.
- the gate terminal voltage of the transistor m2 is the Vreset generator operating signal ENABLE, and the drain terminal voltage of the transistor m2 is the drain terminal voltage of the transistor m3.
- the gate terminal voltage of the transistor ml is the drain terminal voltage of the transistor m3
- the drain terminal voltage of the transistor ml is the source terminal voltage of the transistor m2
- the Vreset generator operating current the gate terminal-source voltage (transistor A certain voltage that satisfies the relationship of m3 drain terminal voltage vs. transistor m1 source terminal voltage)
- drain terminal source terminal voltage is the source of transistor ml.
- the source terminal voltage of the transistor m2 is generated as the reset voltage Vreset.
- the nodes Vc and Vd are set when the comparator 700 is in the reset state.
- the comparator 700 is also brought into the Compara & Latch state. When transitioning, the comparator 700 operates most sensitively.
- the Vreset generator 1000 according to the eighth embodiment related to the dynamic comparator 700 according to the fifth embodiment has a half circuit of the comparator 700 as a replica circuit, and the above-described operation is performed. By generating the reset voltage Vreset by the operation, the dynamic comparator 700 of the fifth embodiment can be operated most efficiently and quickly.
- Vreset generator 1000 shown in FIG. 10 is composed of only the circuit portion constituting one of the differential pairs in the configuration of the comparator 700 shown in FIG. Of course, it may be configured.
- the input transistor unit is an NMOS transistor.
- the NMOS transistor and the PMOS transistor are replaced with the comparator, and the input transistor unit is a PMOS transistor. Similar effects can be obtained.
- FIG. 11 shows the comparator 100 according to the first embodiment, the comparator 400 according to the second embodiment, the comparator 500 according to the third embodiment, or the comparator 7 according to the fifth embodiment.
- 00 or the inverted signal ZC LK of the clock signal to be supplied to the gate terminal of the reset transistor used in the comparator 800 according to the sixth embodiment or the comparator 900 according to the seventh embodiment is generated from the clock signal CLK.
- 2 is a diagram showing an example of the configuration of an inverted clock generation circuit (delay circuit) 1100 for performing
- the inversion clock generation circuit 1100 includes an inverter 1101 and a buffer 1102.
- the input signal of the inverter 1101 is supplied with the clock signal CLK, the output of the inverter 1101 and the output of the buffer 1102 are connected, and the output of the buffer 1102 is output as the inverted signal ZCLK of the clock signal.
- the above is an example of the configuration of the inverted clock generating circuit 1100 of the ninth embodiment.
- a series of operations of the inverted clock generation circuit 1100 of the eleventh embodiment will be described with reference to FIG.
- inverter 1101 When clock signal CLK is applied to inverter 1101, inverter 1101 outputs an inverted signal of clock signal CLK having a predetermined delay. When the inverted signal of the clock signal CLK output by the inverter 1101 is applied to the buffer 1102, the nother 1102 further receives the inverted signal ZCLK of the clock signal CLK having a predetermined delay with respect to the applied inverted signal of the clock signal CLK. Output.
- the inverted signal / CLK of the clock signal CLK output by the inverted clock generation circuit 1100 is used as the comparator 100 according to the first embodiment or the comparator 4 according to the second embodiment.
- 00 or comparator 500 according to the third embodiment 500, or comparator 700 according to the fifth embodiment 700, or comparator 800 according to the sixth embodiment, or comparator 9 according to the seventh embodiment 9 Each comparator can be operated with higher accuracy by applying it to the gate terminal of the reset transistor used in 00.
- the inverted signal ZCLK of the clock signal CLK output by the inverted clock generation circuit 1100 is given to the gate terminal of the reset transistor used in the comparator 100 according to the first embodiment. The operation in this case will be described in more detail.
- FIG. 12 shows the clock signal CLK, the output terminals Q and QB of the comparator 100, the positive output Vol and the negative output Vobl of the first differential amplifier, the positive output Vo2 and the negative output Vob2 of the second differential amplifier.
- the timing chart of the inverted signal ZCLK of the clock signal CLK output by the inverted clock generation circuit 1100 and the voltages of the nodes Va and Vb of the comparator 100 is shown.
- the NMOS transistors ml1, ml2, m21, and m22 of the input transistor section determine the threshold voltage Vtn by performing a predetermined weighting operation, Comparison of the differential voltage between the positive output voltage Vol and negative output voltage Vobl of the differential amplifier 1 and the differential voltage between the positive output voltage Vo2 and negative output voltage Vob2 of the second differential amplifier The result is output to the positive feedback section. Since the predetermined weighting calculation has already been described, it will be omitted.
- a drain voltage VDS1 corresponding to the gate terminal voltage of the transistors mil and ml2 and a drain voltage VDS2 corresponding to the gate terminal voltage of the transistors m21 and m22 are generated, and the positive feedback section is set to VDS1 and VDS2.
- the difference voltage is positively fed back and amplified to the power supply voltage VDD, that is, “High” or the reference ground voltage VSS, that is, “Low”, and this state is maintained (Compare & Latch state).
- VDD power supply voltage
- VSS reference ground voltage
- the comparator 100 according to the first embodiment, the comparator 400 according to the second embodiment, or the comparator 500 according to the third embodiment, or the fifth embodiment.
- the inverted signal ZCLK of the clock signal supplied to the gate terminal of the reset transistor used in the comparator 700 or the comparator 800 according to the sixth embodiment or the comparator 900 according to the seventh embodiment By using the switch that operates in synchronization with the inverted signal of the clock signal having a predetermined delay time with respect to the clock signal CLK in the reset state, the inverted clock generating circuit 1100 for generating the signal CLK generates the signal. It has a function to reset nodes Va and Vb to Vreset or ground voltage VSS.
- the positive feedback section also transitions to the Compare & Latch state because the steady state force with the node Va and vb at the reset voltage also transitions to the Compare & Latch state. Even when the signal frequency and the analog input signal frequency become faster, it is possible to more stably reduce the deterioration of the comparison accuracy.
- the output of the inverter 1101 is given as the input of the buffer 1102, but the clock signal CLK is given to the buffer 1102, and the output of the The same effect can be obtained even if the output is supplied to the inverter 1101.
- the comparator provided with the inverted clock generation circuit 1100 of the present embodiment may be any of the comparators shown in the first to eighth embodiments. Further, when an AZD converter is configured using a plurality of comparators, at least one of the plurality of comparators is provided with a comparator with the inverted clock generation circuit 1100 of the present embodiment. Also good.
- FIG. 13 is a diagram illustrating an example of the configuration of the parallel AZD converter 1300 according to the tenth embodiment.
- the parallel AZD converter 1300 shown in FIG. 1 includes a reference voltage generation circuit 1301, a differential amplifier row 1302, a comparator row 1304, and an encoding circuit 1305.
- the reference voltage generation circuit 1301 reduces the voltage between the high-voltage side reference voltage 1301a and the low-voltage side reference voltage 1301b to less than 2 N (N: number of bits of the AZD converter) m
- the reference voltages VRl to VRm + 1 are generated by dividing by the resistors Rl to Rm.
- VRl to VRm + 1 are input to the differential amplifier row 1302.
- the differential amplifier row 1302 has m + 1 differential amplifiers, and is parallel to the relationship between the analog input signal voltage input from the analog input signal voltage input terminal AIN and the reference voltages VRl to VRm + 1. A predetermined amplification is carried out by and given to the comparator row 1304.
- Each comparator included in the comparator array 103 is supplied with positive and negative outputs of two differential amplifiers adjacent to each other.
- Each comparator employs any of the comparators described above, or has a structure having an inverted clock generation circuit 1100 in these.
- a comparator can be used.
- the input transistors are configured with a predetermined size ratio, and are compared in parallel while interpolating the positive and negative outputs of two adjacent differential amplifiers in synchronization with the clock signal CLK.
- the encoding circuit 1305 logically processes (converts) the comparison result output from the comparator string 1304 and outputs a digital signal DOUT having a predetermined resolution.
- the above is an example of the configuration of the parallel AZD transformation 1300 according to the tenth embodiment.
- the reference voltage generation circuit 1301 includes m resistors Rl to Rm connected in series, and a high-voltage reference voltage 1301a and a low-voltage reference voltage 1301b are applied to both ends thereof. As a result, the voltage between the high-voltage side reference voltage 1301a and the low-voltage side reference voltage 1301b is divided to generate reference voltages VRl to VRm + 1.
- Each of the differential amplifiers Al to Am + 1 constituting the differential amplifier array 1302 has two input terminals. One input terminal is supplied with the analog input signal voltage AIN, and the other VRl to VRm + 1 generated by the reference voltage generation circuit 1301 are applied to the input terminals of the first and second terminals. Each differential amplifier outputs a plurality of output voltage sets, such as a positive output (Vol to Vom + 1) and a negative output (Vobl to Vom + 1).
- Each comparator constituting the comparator array 1304 has any of the configurations of the comparators described above. Since these operations have been described, they are omitted here.
- the encoding circuit 1305 performs logical processing (conversion) on the comparison results output from the output terminals Q and QB by the respective comparators constituting the comparator array 1304, and outputs a digital signal having a predetermined resolution. Is output.
- the parallel-type AZD conversion 1300 of the tenth embodiment is included in the input transistor section of the comparator by configuring a comparator array including a plurality of the comparators described above.
- the interpolation resistor array that has been used in the prior art becomes unnecessary, and the operation current and the occupied area can be reduced. It has a function to reset nodes Va and Vb to Vreset or ground voltage VSS using a switch that operates in synchronization with the inverted signal. Therefore, it is possible to reduce the deterioration of the comparison accuracy of the comparator, which occurred when the clock signal frequency and analog input signal frequency became faster, which was a problem in the prior art. It becomes possible to improve.
- the present invention is not limited to this, and the number of comparators may be any number of powers of 2 (where n is a natural number). The same effect can be obtained.
- the switch for connecting the nodes Va and Vb and the predetermined reset voltage Vreset is an NMOS transistor, but a switch having the same function, for example, The same effect can be obtained by using a CMOS switch that combines a PMOS transistor and an NMOS transistor, or a CMOS switch with a dermy to reduce charge injection.
- the input transistor unit 10 is configured as an NMOS transistor. Even if the NMOS transistor and the PMOS transistor are interchanged and the input transistor unit 10 is configured by a PMOS transistor, the same thing can be achieved. An effect is obtained.
- the present invention can maintain a high comparison accuracy of the comparator even when the frequency of the clock signal and the frequency of the analog input signal are increased.
- the analog input signal bandwidth can be expanded, so the AZD converter for the analog front end of the digital read channel and the system for direct conversion that requires a wide and analog input signal bandwidth. It can be applied to other uses.
Landscapes
- Physics & Mathematics (AREA)
- Nonlinear Science (AREA)
- Engineering & Computer Science (AREA)
- Theoretical Computer Science (AREA)
- Manipulation Of Pulses (AREA)
- Analogue/Digital Conversion (AREA)
Abstract
Description
Claims
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2007550987A JP4646988B2 (ja) | 2005-12-20 | 2006-04-18 | 比較器及びa/d変換器 |
US12/093,565 US7821303B2 (en) | 2005-12-20 | 2006-04-18 | Comparator and A/D converter |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2005-366593 | 2005-12-20 | ||
JP2005366593 | 2005-12-20 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2007072588A1 true WO2007072588A1 (ja) | 2007-06-28 |
Family
ID=38188374
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2006/308143 WO2007072588A1 (ja) | 2005-12-20 | 2006-04-18 | 比較器及びa/d変換器 |
Country Status (4)
Country | Link |
---|---|
US (1) | US7821303B2 (ja) |
JP (1) | JP4646988B2 (ja) |
CN (1) | CN101346880A (ja) |
WO (1) | WO2007072588A1 (ja) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2010109937A (ja) * | 2008-10-31 | 2010-05-13 | Tokyo Institute Of Technology | 比較器及びアナログデジタル変換器 |
JP2013526102A (ja) * | 2010-03-11 | 2013-06-20 | アルテラ コーポレイション | 精密に調整可能な閾値を有する高速差動比較器回路 |
JP2016032159A (ja) * | 2014-07-28 | 2016-03-07 | 株式会社ソシオネクスト | 受信回路 |
KR20190123315A (ko) * | 2017-03-08 | 2019-10-31 | 자일링크스 인코포레이티드 | 다수의 리셋 레벨들을 갖는 동적 양자화기들 |
Families Citing this family (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2010258577A (ja) * | 2009-04-22 | 2010-11-11 | Renesas Electronics Corp | 補間型a/d変換器 |
US8471749B2 (en) * | 2011-07-18 | 2013-06-25 | Freescale Semiconductor, Inc. | Comparator |
US9077320B2 (en) * | 2012-09-20 | 2015-07-07 | Mediatek Inc. | Method and apparatus for performing offset adjustment upon dynamic comparator |
JP2015133617A (ja) * | 2014-01-14 | 2015-07-23 | 株式会社東芝 | 増幅回路、a/d変換器、及び通信装置 |
GB2529686A (en) * | 2014-08-29 | 2016-03-02 | Ibm | High-speed comparator for analog-to-digital converter |
US9602120B1 (en) * | 2016-04-04 | 2017-03-21 | International Business Machines Corporation | Analog to digital converter with digital reference voltage signal |
US9917594B1 (en) * | 2016-09-06 | 2018-03-13 | Texas Instruments Incorporated | Inbuilt threshold comparator |
US9911471B1 (en) | 2017-02-14 | 2018-03-06 | Micron Technology, Inc. | Input buffer circuit |
TWI658701B (zh) * | 2018-02-07 | 2019-05-01 | National Taiwan University Of Science And Technology | 動態電流關聯電路及其應用之比較器及類比數位轉換裝置 |
EP3672077B1 (en) * | 2018-12-19 | 2022-07-27 | Socionext Inc. | Comparator circuitry |
US10505519B1 (en) * | 2019-06-28 | 2019-12-10 | Nxp Usa, Inc. | Dynamic comparator |
CN113437963B (zh) * | 2021-07-09 | 2022-07-08 | 上海芯问科技有限公司 | 比较器、模数转换电路及传感器接口 |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2003069394A (ja) * | 2001-05-30 | 2003-03-07 | Agere Systems Inc | 非相補入力構造を有する比較回路 |
JP2003158456A (ja) * | 2001-09-04 | 2003-05-30 | Matsushita Electric Ind Co Ltd | A/d変換器 |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5997220A (ja) * | 1982-11-26 | 1984-06-05 | Nec Corp | 電圧比較回路 |
JPH0443718A (ja) | 1990-06-11 | 1992-02-13 | Matsushita Electric Ind Co Ltd | 並列型a/d変換器 |
JP3031486B2 (ja) * | 1990-11-30 | 2000-04-10 | 日本テキサス・インスツルメンツ株式会社 | 差動チョッパ形コンパレータ |
US6144231A (en) * | 1998-11-23 | 2000-11-07 | Goldblatt; Jeremy Mark | High speed dynamic latch comparator |
CN1290266C (zh) | 2001-09-04 | 2006-12-13 | 松下电器产业株式会社 | A/d转换器 |
-
2006
- 2006-04-18 WO PCT/JP2006/308143 patent/WO2007072588A1/ja active Application Filing
- 2006-04-18 JP JP2007550987A patent/JP4646988B2/ja active Active
- 2006-04-18 US US12/093,565 patent/US7821303B2/en active Active
- 2006-04-18 CN CNA2006800485487A patent/CN101346880A/zh active Pending
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2003069394A (ja) * | 2001-05-30 | 2003-03-07 | Agere Systems Inc | 非相補入力構造を有する比較回路 |
JP2003158456A (ja) * | 2001-09-04 | 2003-05-30 | Matsushita Electric Ind Co Ltd | A/d変換器 |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2010109937A (ja) * | 2008-10-31 | 2010-05-13 | Tokyo Institute Of Technology | 比較器及びアナログデジタル変換器 |
KR101572931B1 (ko) | 2008-10-31 | 2015-11-30 | 도오쿄 인스티튜드 오브 테크놀로지 | 비교기 및 아날로그 디지털 변환기 |
JP2013526102A (ja) * | 2010-03-11 | 2013-06-20 | アルテラ コーポレイション | 精密に調整可能な閾値を有する高速差動比較器回路 |
JP2016032159A (ja) * | 2014-07-28 | 2016-03-07 | 株式会社ソシオネクスト | 受信回路 |
KR20190123315A (ko) * | 2017-03-08 | 2019-10-31 | 자일링크스 인코포레이티드 | 다수의 리셋 레벨들을 갖는 동적 양자화기들 |
KR102564880B1 (ko) * | 2017-03-08 | 2023-08-07 | 자일링크스 인코포레이티드 | 다수의 리셋 레벨들을 갖는 동적 양자화기들 |
Also Published As
Publication number | Publication date |
---|---|
JP4646988B2 (ja) | 2011-03-09 |
US20090179787A1 (en) | 2009-07-16 |
JPWO2007072588A1 (ja) | 2009-05-28 |
CN101346880A (zh) | 2009-01-14 |
US7821303B2 (en) | 2010-10-26 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
WO2007072588A1 (ja) | 比較器及びa/d変換器 | |
KR101572931B1 (ko) | 비교기 및 아날로그 디지털 변환기 | |
US8198921B2 (en) | Dynamic comparator with background offset calibration | |
US8089388B2 (en) | Folding analog-to-digital converter | |
TWI454062B (zh) | 自我校正的電流源及使用該電流源的數位類比轉換器及其操作方法 | |
US8829942B2 (en) | Comparator and calibration thereof | |
JP6299437B2 (ja) | コンパレータ、電子回路、及びダブルテイルコンパレータの制御方法 | |
JP3113596B2 (ja) | パルス受信機 | |
WO2008020567A1 (fr) | Convertisseur a/n | |
US20170063363A1 (en) | Comparator, electronic circuit, and method of controlling comparator | |
US20110037511A1 (en) | Multiple signal switching circuit, current switching cell circuit, latch circuit, current steering type dac, semiconductor integrated circuit, video device, and communication device | |
US9203381B2 (en) | Current mode logic latch | |
JP3904495B2 (ja) | A/d変換器 | |
US7907075B2 (en) | Semiconductor device | |
CN110235372B (zh) | 一种具有降低回扫噪声的双倍数据速率时间内插量化器 | |
US20070216443A1 (en) | High speed voltage translator circuit | |
TW202008725A (zh) | 鎖存器電路 | |
JP4982830B2 (ja) | 半導体集積回路 | |
US8115550B2 (en) | Transmitter | |
JP5417470B2 (ja) | ダイナミックコンパレータのためのオフセット電圧補正回路とそれを用いたダイナミックコンパレータ回路 | |
EP2945163B1 (en) | Sampling circuit for sampling signal input and related control method | |
WO2011104797A1 (ja) | A/d変換器 | |
JPH0272713A (ja) | 完全差分アナログ比較器 | |
JP5520192B2 (ja) | 電圧電流変換回路 | |
Shukla et al. | A low voltage rail to rail VI conversion scheme for applications in current mode A/D converters |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
WWE | Wipo information: entry into national phase |
Ref document number: 200680048548.7 Country of ref document: CN |
|
DPE2 | Request for preliminary examination filed before expiration of 19th month from priority date (pct application filed from 20040101) | ||
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
ENP | Entry into the national phase |
Ref document number: 2007550987 Country of ref document: JP Kind code of ref document: A |
|
WWE | Wipo information: entry into national phase |
Ref document number: 12093565 Country of ref document: US |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 06745425 Country of ref document: EP Kind code of ref document: A1 |