CN1106080C - Digital/analgue converter - Google Patents
Digital/analgue converter Download PDFInfo
- Publication number
- CN1106080C CN1106080C CN 97103138 CN97103138A CN1106080C CN 1106080 C CN1106080 C CN 1106080C CN 97103138 CN97103138 CN 97103138 CN 97103138 A CN97103138 A CN 97103138A CN 1106080 C CN1106080 C CN 1106080C
- Authority
- CN
- China
- Prior art keywords
- analog converter
- digital analog
- diverter switch
- digital
- output buffer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- 230000005540 biological transmission Effects 0.000 claims abstract description 12
- 238000010586 diagram Methods 0.000 description 3
- 230000007274 generation of a signal involved in cell-cell signaling Effects 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000000903 blocking effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
- 230000001052 transient effect Effects 0.000 description 1
- 230000001960 triggered effect Effects 0.000 description 1
Images
Landscapes
- Analogue/Digital Conversion (AREA)
Abstract
The present invention relates to a digital-analog converter which comprises a control signal generator, a group of CMOS transmission gate change-over switches, a resistor series and an output buffer. A series of digital signals is inputted to the control signal generator so as to generate control signals for controlling the change-over switches and obtain different kinds of node voltage on the resistor series, and the node voltage is outputted by the output buffer so as to obtain analog signals of low distortion.
Description
The present invention relates to a kind of digital analog converter.
General digital analog converter includes a control signal generation circuit mostly, organizes diverter switch more, a resistance string and an output buffer in order to produce different node voltages.Yet the connected mode of the selection of circuit element and each combinational circuit is the key that influences this digital analog converter effect.
Known digital analog converter, its control signal generation circuit is many, and upwards counter (Up-Counter) or a downward counter (Down-Counter) are formed by one; Its shortcoming is that upwards counter or downward counter are when each pulse-triggered; May have many positions changes simultaneously; For example: count to 8 (its binary representation method is 1000) by 7 (its binary representation method is 0111) and may occur 0110,0100,0010 ... transient state numerical value, in very short time moment, open unwanted diverter switch simultaneously; Some noises are also guided to output, seriously influenced the quality of output signal.
Please referring to Fig. 1, it is the analog signal generator structure chart of No. the 4446436th, United States Patent (USP); By understanding among the figure, the node voltage on the resistance string must can be delivered to output through three groups of switches; Because the equivalent resistance of switch can influence the quality of output signal; So through the more organizing switch; Its equivalent resistance is bigger, and the distortion that is caused is also bigger.
Secondly, known digital analog converter uses NMOS or PMOS to do diverter switch more, because the operating voltage range of PMOS and NMOS is little, makes part can't not pass through this switch at the signal of its conducting scope, and serious distortion phenomenon is arranged.
In addition; The equivalent resistance of PMOS and NMOS can change with the change of supply voltage, does diverter switch with pMOS or NMOS, and is voltage-operated down in different electrical power; The output signal of gained has different characteristic (Performance).
Moreover, by PMOS or diverter switch that NMOS constituted; The output buffer that it connected must have certain limitation can reach the purpose of impedance matching; Generally speaking, restriction because of PMOS and NMOS self character, its institute's energy Continuity signal scope is narrower and small and differing from each other, add the consideration of input common-mode range (InPutCommon Mode Range) from operational amplifier, with PMOS is diverter switch, and the output buffer of its connection is the operational amplifier of a NMOS input; And be diverter switch with NMOS; The output buffer of its connection is good with the operational amplifier of a PMOS input then.
Main purpose of the present invention is to provide a kind of digital analog converter that is applicable to extensive supply voltage scope.
Another object of the present invention is to provide a kind of digital analog converter of low distortion.
Another object of the present invention is to provide a kind of digital analog converter of low noise.
The present invention's digital analog converter comprises:
One control-signals generator, described control-signals generator comprise in order to a digital input signals is converted to the ring counter of Gray code and the decoder that described Gray code is decoded into control signal;
Be electrically connected on this control-signals generator to respond one group of diverter switch of this control signal, wherein, this group diverter switch is made of at least one cmos transmission gate;
Be electrically connected on this group diverter switch and have the resistance device of multiple joint, described digital analog converter obtains an analog signal according to the ohmically node voltage of this resistance device, and the switch output one of in this group diverter switch of this node voltage.
Above-mentioned digital analog converter more comprises an output buffer, is electrically connected on this group diverter switch, to reach impedance matching.
In the above-mentioned digital analog converter, this ring counter is made up of at least one trigger.
In the above-mentioned digital analog converter, this cmos transmission gate is formed in parallel by a PMOS and a NMOS.
Above-mentioned digital analog converter, this resistance device with multiple joint is formed by a plurality of resistance serial connections.
Above-mentioned digital analog converter; This output buffer is the operational amplifier of PMOS input or the operational amplifier of NMOS input.
In the above-mentioned digital analog converter, this analog signal is a sine wave.
Nationality of the present invention is by following accompanying drawing and detailed description; Can get a more deep understanding.
Fig. 1 is the circuit connection diagram of No. 4446436 patent of the U.S..
Fig. 2 is the circuit connection diagram of the present invention's digital analog converter each several part.
Fig. 3 is the ring counter circuit diagram in the present invention's the control-signals generator.
Fig. 4 for the decoder circuit figure in the present invention's the control-signals generator,
The Gray code that Fig. 5 is produced by the present invention's ring counter.
Fig. 6 is the control signal of the present invention's Gray code through a decoder output.
See also Fig. 2, the present invention's digital analog converter, its control code generator 30 receives a pulse signal, its output 1-16 is connected to the cmos transmission gate diverter switch 31-46 of one-level diverter switch 65 respectively, this cmos transmission gate change over switch 31-46 is connected with resistance string 64 respectively, and this resistance string 64 forms its tool two power supply end points VH, VL by resistance 47-62 serial connection; The output of this diverter switch 31-46 is connected in and is connected to output buffer 63 on the same line again
The present invention's digital analog converter, its control code generator 30 is made of a ring counter 40 and a decoder 50.As shown in Figure 3, this ring counter 40 is made up of 16 triggers.When a digital signal is failed this control code generator 30 of people; Ring counter 40 just changes into this digital signal Gray code QI-Q16 (as shown in Figure 5); And decoder 50 is decoded into control signal LI-L16 (as shown in Figure 6) with this Gray code QI-Q16.
This control signal LI-L16 controls the action of this diverter switch 31-46, because this control signal L1-L16 is when each pulse input, have only a position state to be " 1 ", all the other are all " 0 ", so all have only a diverter switch can allow one among this diverter switch of node voltage value mat 31-46 of resistance string 64 to be transferred to output buffer 63 at any one time; Deliver to output again, the analog signal of synthesizing a near sinusoidal ripple with the node voltage value of this difference.
The present invention's digital analog converter produces Gray code Q1-Q16 with ring counter 40, and cooperates decoder 50 to decipher out control signal L1-L16.The characteristic of this control signal is to control this diverter switch 31-46 and all have only a diverter switch conducting at any one time, so all can only there be a node voltage value to be sent to output at any one time; Avoid having too many position to change simultaneously unnecessary node voltage is also delivered to output and causing noise because of the same time.
The present invention's digital analog converter, the node voltage value on its resistance device only need just can deliver to output through an output buffer 63 through a diverter switch.So,, just can reduce because of the distortion that influence caused of diverter switch equivalent resistance.
Certainly, the present invention's digital analog converter; Its diverter switch 31-46 is made of 16 cmos transmission gates, and each cmos transmission gate all by a PMOS and a NMOS be formed in parallel, since the equivalent resistance of PMOS can reduce with the reduction of supply voltage, the equivalent resistance of NMOS can increase with the reduction of supply voltage, so this equivalent resistance once the cmos transmission gate diverter switch that formed by a PMOS NMOS in parallel can not change because of the variation of supply voltage, even under different supply voltage operations, output signal still has identical characteristic.
Secondly, by the cmos transmission gate that PMOS A NMOS is formed in parallel, its conducting voltage scope is big far beyond the conducting voltage scope of single PMOS and single NMOS, the distortion of avoiding signal to be caused by blocking.
The present invention's digital analog converter; More comprise an output buffer 63, as the usefulness of impedance matching.Because this diverter switch 31-46 is made of cmos transmission gate,, increased the elasticity of selecting element for use so the output buffer 63 of its connection can select for use the operational amplifier of a CMOS input or the operational amplifier of a CMOS input to realize.
Certainly, digital analog converter of the present invention can respectively be formed the resistance value of resistance by changing this resistance string; Obtain difform analog signal.
In sum; The present invention's digital analog converter not only can be used in vast supply voltage scope, more can reduce the noise and the distortion of output signal.
Claims (8)
1. digital analog converter is characterized in that comprising:
One control-signals generator, described control-signals generator comprise in order to a digital input signals is converted to the ring counter of Gray code and the decoder that described Gray code is decoded into control signal;
Be electrically connected on this control-signals generator to respond one group of diverter switch of this control signal, wherein, this group diverter switch is made of at least one cmos transmission gate;
Be electrically connected on this group diverter switch and have the resistance device of multiple joint, described digital analog converter obtains an analog signal according to the ohmically node voltage of this resistance device, and the switch output one of in this group diverter switch of this node voltage.
2. digital analog converter as claimed in claim 1 is characterized in that more comprising an output buffer, is electrically connected on this group diverter switch, to reach impedance matching.
3. digital analog converter as claimed in claim 1 is characterized in that this ring counter is made up of at least one trigger.
4. digital analog converter as claimed in claim 1 is characterized in that this cmos transmission gate is formed in parallel by a PMOS and a NMOS.
5. digital analog converter as claimed in claim 1 is characterized in that this resistance device with multiple joint is formed by a plurality of resistance serial connections.
6. digital analog converter as claimed in claim 2; It is characterized in that this output buffer is the operational amplifier of PMOS input.
7. digital analog converter as claimed in claim 2 is characterized in that this output buffer is the operational amplifier of NMOS input.
8. digital analog converter as claimed in claim 1 is characterized in that this analog signal is a sine wave.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 97103138 CN1106080C (en) | 1997-03-04 | 1997-03-04 | Digital/analgue converter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 97103138 CN1106080C (en) | 1997-03-04 | 1997-03-04 | Digital/analgue converter |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1192612A CN1192612A (en) | 1998-09-09 |
| CN1106080C true CN1106080C (en) | 2003-04-16 |
Family
ID=5166553
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 97103138 Expired - Fee Related CN1106080C (en) | 1997-03-04 | 1997-03-04 | Digital/analgue converter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1106080C (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE50209650D1 (en) * | 2002-04-09 | 2007-04-19 | Infineon Technologies Ag | Device for converting a digital value into an analog signal |
| US7019676B2 (en) * | 2003-06-12 | 2006-03-28 | Matsushita Electric Industrial Co, Ltd. | D/A converter |
| CN101908887B (en) * | 2009-06-05 | 2014-04-30 | 丰田自动车株式会社 | DA (Digital Analogy) conversion device |
| CN102118172B (en) * | 2009-12-31 | 2014-07-30 | 意法半导体研发（上海）有限公司 | Device and method for simplifying digital-to-analogue converter circuit by using Gray code |
| CN104768290B (en) * | 2012-12-28 | 2017-06-09 | 电子科技大学 | Multipath current-source switching device |
| CN108551345A (en) * | 2018-04-19 | 2018-09-18 | 南通大学 | A kind of multichannel single choice type D/A converter |
| CN108566205A (en) * | 2018-04-19 | 2018-09-21 | 南通大学 | A kind of D/A converter realized based on FPGA |
-
1997
- 1997-03-04 CN CN 97103138 patent/CN1106080C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CN1192612A (en) | 1998-09-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6686865B2 (en) | High resolution, high speed, low power switched capacitor analog to digital converter | |
| US6268817B1 (en) | Digital-to-analog converter | |
| CN1122973A (en) | Digital-to-analog converter with reduced number of resistors | |
| US8023671B2 (en) | Piezoelectric buzzer driving circuit | |
| CN1829085A (en) | Tri-state pulse density modulator | |
| DE102016111432B4 (en) | Multi-stage digital-to-analog converter | |
| CN1106080C (en) | Digital/analgue converter | |
| EP0708530A1 (en) | Current source driven DA converter and AD using the same | |
| EP1380112A2 (en) | Digital to analogue converter | |
| WO2021036610A1 (en) | Digital-to-analog converter of r-2r ladder-shaped network architecture | |
| CN1165435A (en) | Output buffer circuit | |
| CN1237290A (en) | Method and device to provide high-performance digital-to-analog conversion architecture | |
| JP3361848B2 (en) | Apparatus for generating a digital signal output representative of a received analog signal | |
| KR100311043B1 (en) | Digital-to-analog converter capable of fast switching and precision voltage conversion | |
| US6181265B1 (en) | Non-linear digital-to-analog converter | |
| US4446436A (en) | Circuit for generating analog signals | |
| CN1402908A (en) | Digital-to-analog converter | |
| JPH01501830A (en) | Digital receiver with double reference | |
| CN1126260C (en) | Resistor string D/A converter with pulse width modulation output | |
| US7088274B2 (en) | Difference amplifier for digital-to-analog converter | |
| US6278393B1 (en) | Multiple output digital-to-analog converter | |
| US6127959A (en) | Flash analog-to-digital converter with reduced number of resistors and comparators | |
| JPS6373718A (en) | R-2r type d/a converter circuit | |
| US7242267B2 (en) | Interpolating programmable gain attenuator | |
| KR910002341B1 (en) | Analog signals comparting circuit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C06 | Publication | ||
| PB01 | Publication | ||
| C53 | Correction of patent for invention or patent application | ||
| COR | Change of bibliographic data |
Free format text: CORRECT: APPLICANT; FROM: HETAI SEMICONDUCTOR CO., LTD. TO: SHENGQUN SEMICONDUCTOR CO., LTD. |
|
| CP03 | Change of name, title or address |
Address after: No. three, No. two, Hsinchu Science Industrial Park, Taiwan Applicant after: Shengqun Semiconductor Co., Ltd. Address before: No. five, No. two, Hsinchu Science Industrial Park, Taiwan Applicant before: Hetai Semiconductor Co., Ltd. |
|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C19 | Lapse of patent right due to non-payment of the annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |