TW200807854A - Circuit for generating voltage and current references - Google Patents

Abstract

The circuit for generating voltage and current references is to provide two voltage references and one or more current references with low temperature coefficient and low supply-voltage sensitivity. The circuit comprises the first and second diode-connected NMOS, a plurality of PMOS, a resistor with low temperature coefficient and an operational amplifier. The features include: (1) the first and second diode-connected NMOS have their own unique the first and second smallest temperature coefficient points, respectively. Both have different gate-source voltages for the two NMOS. (2) the resistor is connected to the first input of the operational amplifier and the drain of the second diode-connected NMOS. (3) The first and second inputs of the operational amplifier are connected to the resistor and the drain of the first diode-connected NMOS, respectively. The output of the operational amplifier is connected to a plurality of PMOS for adjusting the drain currents of the first and second diode-connected NMOS biased in the neighborhood of the first and second smallest temperature coefficient points providing two stable voltage references and one or more stable current references.

Description

200807854 t, invention description (1) Technical Field of the Invention The present invention is a generation circuit capable of simultaneously generating a reference voltage source and a current source, which can generate two stables with low temperature coefficient and low supply voltage sensitivity. The reference voltage level and one or more stable current reference sources are suitable for the implementation of a stable reference voltage source and a current source in the mixed signal integrated circuit, the analog integrated circuit and the system chip. [Previous technique] " Press, the voltage source or current source widely used in the low temperature effect of the integrated circuit is a bandgap approach because the technology requires the use of a bipolar transistor or a diode. However, in the CM0S process or digital process, only parasitic bipolar transistors and diodes are available, which have poor performance and occupy a large amount of wafer area, and the cost of the wafer is relatively high. Regarding the reference voltage source or current source design of all CMOS transistors, there is a N Μ 0 S transistor that connects a diode connection mode to its minimum temperature coefficient point. However, only one temperature variation is used. The minimum temperature coefficient point is equivalent. It is not easy to implement in circuit. The main reason is that the minimum temperature coefficient point has two degrees of freedom. One is the gate of the transistor, and the other is the gate of the transistor. The voltage, as long as either one changes due to temperature changes, the transistor cannot be biased at the point of minimum temperature coefficient. ' Invention content

200807854 V. INSTRUCTIONS (2) There are many applications for modern microelectronic components that need to be operated in harsh environments, such as the aerospace industry and the automotive industry. Electronic components often need to be operated at temperatures greater than 120 degrees or below -2. In a 0 degree environment, it is therefore an increasingly urgent challenge to design a stable voltage source and current source that can operate over a wide range of temperatures. In addition, a stable reference voltage source or current source is a mixture of many mixed signal integrated circuits and analog products. The basic components of the body circuit design, such as oscillation. =, phase-locked loop and data converter, etc., the circuit design specification requirements often require low temperature coefficient and low supply voltage sensitivity. The main tasks are: (1) using two NM〇s transistors with different minimum temperature coefficients and ^ diode connection. The so-called minimum temperature 糸U is the 汲 of the temple M0.S transistor. Current and gate-source voltage change = minimum; (b)! Use a low temperature coefficient resistor, NM0S 曰曰 body and a different amplifier to connect the above two diodes to the invention. The crystal is biased near its individual minimum temperature coefficient point, so the current thick source 2 ^ t is enough to generate a stable reference to the temperature and supply voltage; soil, original and current source. The minimum temperature coefficient point has the invariant temperature characteristic, so the original month " has the following effects: , ((:))::: a stable voltage source and one or a plurality of stable current sources; (three = The voltage source and current source have the characteristics of low temperature coefficient; special ^). The voltage source and current source have low supply voltage sensitivity. 4. The circuit structure is simple and easy to implement.

200807854 Ear, invention description (4) € voltage, change the electric current bias to one (four) first stable (five) second stable (six) one or the same size of PM0S (seven) the fifth picture is the average output Voltage VIII) The sixth picture shows the average output voltage of g (9). The seventh picture shows the peak current of the average output current crystals M1 and M2, so that the transistors M1 and M2 are near the minimum temperature coefficient point; the reference voltage source is connected by the node. η 1 is taken out; the reference voltage source is taken out by the node η2; a plurality of reference current sources can be obtained by connecting one or a plurality of non-transistors such as Μ5 and Μ6 in parallel; the first stable reference voltage and temperature relationship diagram of the simulation is 1.2713 The average temperature coefficient is 11.8 0?111/°(:;; the second stable reference voltage of the simulation is related to the temperature, which is 823·4 mV, and the average temperature coefficient is 4.6 ppm/°C; A plot of current source versus temperature, 1 1 2 . 6 u A, with an average temperature coefficient of 2 9. 2 ppm / °C.

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^戚[Embodiment]: This rabbit is mainly used with two points with different minimum temperature coefficients; two diode-connected NM0S transistors are shown in the fourth figure; the so-called most | small temperature coefficient point system It means that the value of the drain current and the gate-source voltage of the M0S transistor is minimally changed by temperature, as shown in the second and third figures, which are in accordance with the definition of the minimum temperature coefficient point of the M0S transistor of the present invention. The main design I concept is based on the minimum temperature coefficient point I丨 of the two diode-connected NM0S transistors, as shown in the fourth figure, by designing the resistance to the resistance value, as shown in the first figure I, The two diode-connected NM0S transistors are biased near their respective minimum temperature coefficient points, and the circuit of the present invention can provide two stable reference I because the influence of the temperature coefficient is small near the minimum temperature coefficient point. Press with one or more stable current reference sources. :! The detailed implementation of the circuit (as shown in the first figure) is as follows: , : 丨 () I Han Han two NM0S transistors (mi and M2) are biased in the individual small temperature The coefficient point is near the fourth picture, and its individual minimum _: 丨 temperature coefficient point position is different, so the transistor U1 is biased to the immersion current is $ idl and the gate-source voltage is v(nl), the transistor M2 Then the bias voltage is the current of the pole & the Id2 and the gate-source voltage are V(n2); b) the resistor of a low temperature coefficient is used, and the resistance of the resistor satisfies R1= _V(nl)-V(n2) ) / Id2 design relationship; Bao (b) uses a different amplifier's two inputs are connected with the node and j|n3 respectively, due to the assumption of virtual short circuit, the node nl and the almost phase I: etc. That is, V(nl)=V(n2) + Id2xRl is satisfied. If it is not satisfied, the control voltage is outputted through the output of the operation amplifier, and the idle poles of the transistors M3 and M4 are adjusted.

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Claims (1)

200807854 A reference voltage source and current source generating circuit for generating two stable reference voltage levels and/or one or more stable reference current sources that are unaffected by temperature, and/or supply voltage variations, including an operation An amplifier having first and second signal inputs, and an output; a resistor having a temperature coefficient of less than 1. 0E-4 ppm/°C; a first diode connected NM0S transistor for generating stability The first reference voltage level is rotated; a first P Μ 0 S transistor crystal immersed current; f second diode connected NM 〇 s transistors for generating a stable second g reference voltage a level output; a second PMOS transistor for generating a first diode connection, a second PMOS transistor for generating a second diode connected NM0S transistor; | one or a plurality of the same or different sizes The PM0S transistor is used to generate one or a plurality of stable reference current sources; 1 2. The reference voltage source and the current source of the first application of the scope of claim 1 are not subject to temperature and/or supply voltage. The dynamic influence refers to the disturbance of the two stable reference voltages and one or more stable reference current sources only when the temperature or the supply voltage fluctuates, compared with a circuit; I | 3. For example, the reference voltage source of claim 1 and the current source I of the current source have a first most small temperature coefficient point in the NM0S transistor in which the first diode is connected; 200807854 "ji_ _, the scope of application for patent 4. If the reference voltage source of the patent scope 1st, the production of the current source, the second diode connection of the NM0S transistor 71 is in " Small temperature coefficient point; ~ ^ 5 · The reference voltage source of the third application of the patent scope and the current source of the current source, the first diode connected to the NM0S transistor is biased to the first % minimum temperature Near the coefficient point, used to generate a stable first reference voltage level output, : sac. · For example, the reference voltage source of the fourth application of the patent scope and the current source / / the second diode connected to the NM0S The transistor is biased near the second most jp small temperature coefficient point to generate a stable second reference voltage level, and the source of the reference voltage source and the current source is applied as in the scope of claim i. In the circuit, the first diode of the NM0S transistor is connected to the resistor and the resistor. 8. The reference voltage source of the first application of the patent scope and the current source of the current source 'Ice, the younger brother _PM0S Crystal immersion, resistance and operational amplification The second round inlet is connected; the mouth is as good as the reference voltage source and the current source of the first application patent. The first one of the 3os i - the top of the PM 〇 S transistor, the second to the second pole Body connection: in 'the crystal of the anode is connected with the first round of the operational amplifier; the road, the full reference of the patent source range of the reference voltage source and the current source of the output of the PM0S electricity and the first - The PM〇S transistor and the gate of the second child's body are connected; 11 · The reference voltage source and the current source of the first application of the patent scope are generated. 200807854 200807854). 〇 version) application case name: reference voltage source and current source generation circuit Page 6/15 1111111 Λ: .i Page 8/15 III Brother 8/15 2〇〇807854;.〇版) Application Case Name: Reference Voltage Source and Current Source Generation Circuit Page 13d5 Page 14/15