TW201009309A - Temperature sensing circuit - Google Patents

Abstract

A temperature sensing circuit is provided, which includes a bandgap reference voltage generator and a comparison module. The bandgap reference voltage generator outputs a reference voltage and a reference current. The comparison module generates a sensing voltage corresponding to a temperature variation according to the reference current and then outputs a stop signal corresponding to a specific temperature by comparing the sensing voltage with the reference voltage. Thereby, the temperature sensing error caused by process variations is compensated and the temperature sensing accuracy and the sensitivity are increased.

Description

^<5934twf.doc/n 201009309 IX. Description of the Invention: [Technical Field of the Invention] The present invention relates to a temperature measuring circuit, and more particularly to the use of a current generated by a bandgap reference voltage generator. A temperature detection circuit that overcomes the voltage difference of the process disk. μ [Prior Art] With the advent of the information age, not only has the popularity of personal computers been accelerated, but φ has also spurred the market for computers and peripheral devices. Therefore, all kinds of information products are constantly being updated, and various types of information equipment are also diversified. However, with the improvement of the performance of electronic systems and the increasingly thin design requirements, the first problem is the working hours. More and more heat is emitted. For example, in the current trend of technology, the operating frequency of the Central Processing Unit 'CPU, the Graphics Processing Unit' GPU, and its peripheral circuits is constantly increasing. Come to the more. In order to ensure that the above-mentioned central processing unit, graphics processing unit and its integrated integrated circuit (1C) can work normally without being burnt due to high temperature, the monitoring of temperature has become a very important one. thing. There is a hardware monitor ic (Hardware Monitor 1C) on a typical motherboard or display card for this task. The principle is that the voltage difference across the temperature sensing diode will change with different temperatures'. About every 1 °C change, the voltage difference between the two poles is reduced by 2mV. Therefore, by measuring the temperature difference between the two ends of the temperature sensing diode 5 201009309 ,8934twf.doc / n indirectly know the current ambient temperature, for example, to obtain the current temperature of the central processing unit. However, the temperature difference between the above temperature sensing diodes is 2_2ιην/. The relationship of ^ will change with the process factor*. As the body changes, there will be different offset voltages (full et read), which is a very big problem for the establishment of the control relationship between = and / or. SUMMARY OF THE INVENTION The present invention provides a temperature detecting circuit that utilizes a current inside a bandgap reference voltage generator (bandgap reference v〇ltagegenerat〇r) to generate a current required for operation of a temperature detecting circuit, thereby compensating for a cause ^The resulting temperature_county, the correctness and sensitivity of the temperature side is improved. The present invention proposes a temperature_circuit comprising a bandgap reference voltage generator and a comparison module, wherein the first reference current can be compared; Module = β 'test electricity' "1 · generate 4 贞 ' voltage, and compare the reference voltage with the b = voltage to stop I · u ' where the stop signal corresponds to a ^ temple: in = Ming - In the embodiment, the above-mentioned energy gap reference voltage 経 second current source is used to generate a second reference current; and f is connected to the first electrical surface, and according to the upper 2::: test current; wherein the above energy gap The reference voltage is generated = the reference current is generated by the reference current. In an embodiment of the invention, the comparison module includes a temperature sensing circuit 201009309 _η = and - comparative benefit, the radiation temperature sensing resistor is lightly connected between the upper and the ground terminals, and the pin temperature is 4 _ upper two gaps 贞 light; and comparator _ in the above mentioned reference county and the above detection depends on outputting the above stop signal. It is higher than the temperature on the rut. In the example, the temperature sensing resistor has a one-degree coefficient.

In the embodiment of the present invention, the bandgap reference voltage generator further includes a band gap reference circuit _ for the first current source and the grounding, and the second node is used to generate the first node and the second node. And the second operational amplifier is configured to adjust the voltage to the first current source to adjust the second reference current according to the first node voltage and the second node voltage output. In an embodiment of the invention, the operational amplifier includes a third current source 'contacting the first current source, and the second reference current is generated by the second reference current; the differential current is connected to the first a three current source, between the ground terminals, and according to the first node voltage and the second node voltage output-differential voltage; and an output stage circuit, connected to the difference, the amplifier, and according to the differential voltage output The adjusting voltage is applied to the first, second and third current sources to adjust the first, second and second reference currents.

In an embodiment of the invention, the output stage circuit includes a PMOS metal oxide semiconductor transistor and an NMOS transistor (N channel metal 〇xide semic〇nduct〇r 7 ^8934twf.doc/n 201009309 transistor), wherein one end of the PM〇s transistor is coupled to a voltage source 'the PMQS transistor closes the first current source to correspond to one of the second reference currents and a fourth reference current; and the upper NM The 〇S transistor is lightly connected between the other end of the PMOS transistor and the grounding end, and the gate of the 〇8 transistor is coupled to the PMOS transistor and the above-mentioned nm〇S in the differential voltage VIII A second common node of the transistor is coupled to the gate of the PMOS transistor, and the first common node is configured to output the adjusted voltage. In an embodiment of the invention, the energy gap reference voltage generator further includes a PMOS transistor and a bipolar transistor, and the handle body is connected between the voltage source and the resistor. 4 The PMOS transistor: Connected to the first current source ′ and the bipolar transistor is coupled between the one end of the body and the ground end and the bipolar electro-optic t grounding end pin, the electric _ one of the electric 曰曰The two shared nodes output the above reference voltage. In one embodiment, the first current source is -the first and the second current source is a second occupational crystal, and the body is coupled to the idle pole of the second pmos transistor to form A current mirror. In an embodiment of the invention, the gap reference circuit includes: a JL V motor source and a bipolar transistor, and the other end and the base of the 5: body are coupled to each other. The grounding is fine, and a second resistor is coupled in series with the second resistor of the flute and the second resistor, and is coupled between the first current and the bipolar transistor, and the second bipolar transistor is Another ^8934twf.doc/n 201009309 one end and the base are both at the grounding end, wherein a second common node of the first bipolar transistor on the first resistive disk outputs the first voltage step 'the first resistance And outputting the second node voltage by the second bipolar electric one or two. In the other embodiment of the present invention, the energy gap reference voltage is generated by a first PM〇S transistor, and the handle is connected to a voltage source and a -N-^ Between the 曰曰 ^ 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二 第二a first current source; the bipolar transistor is entangled in the above-mentioned first-view 〇= and the other end of the upper T bipolar transistor and the base are both the second T and the second bipolar transistor, connected to the first resistor : Ϊ端和上私"The other end of the double-recording transistor is _ in the above-mentioned "the gate of the above-mentioned -PM0S transistor is lightly connected to the interesting transistor and the first NM0S transistor" The first NMOS transistor and the second NMos transistor are connected to each other, and the gate of the second NMOS transistor is coupled to the second crystal and the second sf crystal. Shooting the above (four) reference voltage generation = 夕 „ ^ PM〇s transistor 'hybrids connected to a voltage source and - second Christine B ' and the above second PMQS transistor Hard secret to the second 9 ^ 8934twf.doc / n

201009309 PMOS transistor gate; and a third bipolar transistor, between the second electric_the other end and the grounding end, and the base of the crystal is coupled to the grounding end, wherein the third The resistor and the fourth common node of the second PMOS transistor output the reference voltage. In an embodiment of the invention, the second reference current is equal to the first reference current. In an embodiment of the present invention, The bipolar transistors are all pN? bipolar junction transistors. The invention detects the temperature by using the reference voltage of the bandgap reference voltage generator and the reference current generated therein, so that the current and voltage drift caused by the process difference can be compensated by the reference current to increase the temperature. The correctness of detection and its sensitivity. The above described features and advantages of the present invention will be more apparent from the following description. [Embodiment] The energy gap reference ink generator is mainly used to generate a reference with temperature and process benefit (which is less affected by it). The general energy gap reference voltage generator mainly utilizes two current paths and The base-emitter voltage of the pNp bipolar electric junction (biP〇lar junction transist〇r)

The reference voltage is generated with a temperature-free reference voltage U, and the reference currents in the two internal current paths are automatically adjusted to reduce the output reference voltage. In other words, (4) Reference (generated) The (IV) reference current is adjusted with the degree of the dish, the correction and the operating voltage. The implementation is based on the internal reference current of the energy gap ^934twf.d〇c/n 201009309 reference voltage generator to generate the working current of the temperature detecting circuit to reduce the temperature detection error caused by the process difference. First Embodiment Referring to Figure 1, there is shown a temperature detecting circuit in accordance with a first embodiment of the present invention. The temperature detecting circuit 100 includes a bandgap reference voltage generator 11 and a comparison module 120, wherein the bandgap reference voltage generator 11 is used to generate a reference voltage VBGR and a reference current I, and the comparison module 12 is based on a reference voltage The machine generates a detection voltage ντ, and compares the reference voltage VBGR with the detection voltage VT to output a shutdown signal STP. The comparison module 120 includes a temperature sensing resistor Rii and a comparator. Bandgap reference voltage generator UG _ pM〇s transistor connected to voltage source VDD and temperature sensing resistor % gate t reference voltage fine llG (10) circle = threat t should be reference current l2 Ο temperature sensing resistor km at the other end of the light At the ground GND, the temperature sensing resistor "and the common node between the pM〇s transistors outputs the corresponding temperature sensing.

• m _ in the temperature sensing resistance ^ with the occupational crystal P common lang point and Μ reference voltage generator 11G = self-test voltage VT and the participant thunder vpm out 乂 than the rut detection stop signal corresponds to a special Two = out - stop signal STP 'on main =: body: =, _ road body VOS transistor Pi4, PM 〇 S electric crystal circuit U2, differential amplifier 114, sHPl5, energy gap reference transistor n13, resistor r14 11 ▲3934twfd〇c/n

201009309 and the foot bipolar transistor Bl3. The bandgap reference circuit 112 further includes resistors Ru, Rl2, Ri3, and pNp bipolar transistor Bn, Bl2 '* differential amplifier 114, including pM〇s transistor ^ and NMOS transistor N11, N1" ρ_Optical crystal differential amplifier m, m〇s transistor Pi4 and NM〇s transistor ^ - operational amplifier, while PM0S transistor PM and electric 3 crystal ΝΠ can be regarded as the operational amplifier's wheel-out stage circuit. In the gap reference circuit m, the PMQS f crystal source VDD and the resistors Rn, R 2 are used to provide a bandgap reference voltage = f2 test current L. The resistor is between the other end of the resistor ^ and the transistor B12. The emitter_base_ of the bipolar transistor Bi2 is connected to the ground GND. The bipolar transistor Bu is coupled between the other end of the resistor Ru and the ground GND, and the base is also connected to the ground. The common node output of the transistor Bu and the resistor & is the point voltage V, and the bipolar transistor % and the voltage of the resistor ~ point to output a second node voltage V2. ', the dynamic amplifier 114, PM0S Between the crystal voltage source / PMOS transistor P16, p17, to provide the differential amplifier = the required reference current l3. The gates of the M0S transistors &Pi7 are respectively connected to the first node voltage vi and the second node voltage V2, and the nm〇s transistors Νπ and N12 are respectively switched to the other ends of the PM0S transistors pi6 and pi7. Between the ground and the ground GND, and the gates of the NM0S transistors Nu, & are lightly connected to each other' wherein the idler of the NMOS transistor Nn is lighter than the pM〇s transistor P i6 and the NMO S transistor N! 12 -8934twf.doc/n 201009309 The output circuit of the MOS transistor Pl4 and the NMOS transistor Ni3 is connected to the differential amplifier 114, and the output is adjusted according to the differential voltage DV output from the differential m. Voltage ^ to the shirt (10) The gate of the transistor Pn ~ Pls to adjust the reference voltage generated by it. In terms of circuit structure, the adjustment voltage of the operational amplifier is used to adjust the reference generated by the PMOS reduction P11. The current h affects the energy gap reference voltage by H 11G. However, the gates of the PMOS transistors P11 to Pl5 are connected to each other and form a mirror, so when the reference current ^ changes, the remaining reference current I4~is^J changes accordingly. In other words, the reference of the PMOS transistor P12 is turned on. It will also adjust its current value according to the process difference. pM〇s electro-crystal ^ Pu~P!5 can be regarded as a current source respectively, and the reference electric steam generated by it 0曰= has corresponding _ or do, reference current W5 The electric yaw value is determined by the component size of the 5 PMOS PMOS transistor pu~pls respectively. The PM 〇s transistor resistance in the bandgap reference voltage generator 110 is mixed with the brewing > bipolar transistor Βπ The voltage source vdd == between the terminals GND, and the base of the PNp bipolar transistor & is also coupled to the ground GND. The resistor and the PM〇s transistor are used to output the reference voltage VBGR. The reference voltage ν Β 'two temperature-independent voltage. Energy gap reference electric waste generator 110 utilizes positive temperature production

The voltage has a negative temperature coefficient ΡΝΡ bipolar transistor to S = degrees without _ reference voltage VBGR. Strictly speaking, it should be the theoretical reference voltage VBGR with less temperature influence. It should be noted that in the present embodiment, the reference current 13 used in the bandgap reference voltage generator 13 201009309 8934twf.doc/n is used as an operational amplifier for adjusting the reference voltage with reference power feedback. Independence; count, the difference between the two major devices (4) reference current rap will follow, put 110 reference current I〗.耆 4. The reference voltage generator coefficient has a positive temperature and changes with temperature. As long as the detection voltage ντ is set to the reference = voltage relationship, the corresponding specific temperature can be measured. It is worth noting that the reference current generated by the 'PM0S transistor 施 in the example will be affected by 4, because νττ is also the material current i2: it: by using the bandgap reference voltage generator U〇 will adjust the reference current i2 according to the difference of the process difference 2 to test the current l to reduce the influence of the process difference on the detection voltage ντ, so that the detection light ντ can more accurately correspond to the pre-discrimination Temperature value. In other words, in this embodiment, the detection voltage VT is generated by using a reference current l2 which is inversely adjusted with the process difference, thereby offsetting the influence of the process variation. The comparator 130 is configured to compare the detection voltage VT with the reference voltage VBGR to rotate a shutdown signal STp, and the shutdown signal STp corresponds to a special

疋 Temperature. When the detection voltage VT is greater than the reference voltage VBGR, the shutdown signal STP is at a logic high potential ' indicating that the circuit temperature has exceeded the preset temperature. When the detection voltage VT is less than the reference voltage VBGR, the shutdown signal STP is logic low, indicating that the circuit temperature has not reached the preset temperature. Of course, in another embodiment of the present invention, the detection voltage ντ may be reversed with the reference voltages VBGR 201009309 , J934twf.doc/n to generate the shutdown signal STp of different voltage levels, which is limited in this embodiment. The second embodiment has a plurality of methods for the energy gap reference voltage generator, and is not limited to the above-described first embodiment. Please refer to FIG. 2, which is a temperature detecting circuit 200 according to a second embodiment of the present invention, wherein FIG. 2 The main difference from FIG. j is the internal circuit structure of the bandgap reference voltage generator 210. In Fig. 2, the reference currents l21, l22 in the energy gap reference voltage generator 210 are generated by current mirrors formed by the PMOS transistors PZ1, P22. The PM〇s transistor Pu is connected between the voltage source VDD and the NM0S transistor N21, and the PM〇s transistor P22 is coupled between the voltage source VDD and the resistor R3, and the PM〇s transistor P21 and The gate of PMOS transistor p22 is decoupled to form a current source to generate reference currents 21 and I22. The PNP bipolar transistor B11 is coupled to the other end of the facet transistor %' and the PNP bipolar transistor B„(4) is secluded to the ground GND. The PNP bipolar transistor Bi2 is consumed by the resistor. The other end of the bipolar transistor B12 is connected to the ground GND. The gate of the PMOS transistor P21 is coupled to the pM〇s transistor 匕 and the NMOS transistor N21. The node, the read 电8 transistor % and the 〇8 transistor N22 gate are mutually connected, and the closed-pole handle of the NM〇s transistor A is connected to the common node of the PMOS transistor P22 and the NM〇s transistor N22. The circuit structure of the PMOS transistor P15, the resistor 'and the double crystal transistor B!3 is the same as that of the figure i, and will not be described again. It is worth noting that in Fig. 2, the gate of the PMOS transistor p12 is lightly connected. (10) The gate of the transistor 15 z8934twf.doc/n 201009309, generates a corresponding reference current I23 in the form of a current mirror. In other words, in the present embodiment, the current I23 through the temperature sensing resistor R is also the same. As the reference within the bandgap reference voltage generator 210, the streams IZ1, I22 change, thereby generating And the temperature-dependent reference current la, the correspondence between the detection voltage VT and the temperature can be more accurate, and is not affected by the process difference. For the remaining technical details of FIG. 2, please refer to the above embodiment of FIG. Note that FIG. 3 is a temperature detecting waveform diagram according to the above embodiment. When the measured voltage VT is greater than the reference voltage VBGR, the shutdown signal _ is the fascinating surface potential, indicating that the circuit temperature has exceeded Considering the specific temperature L. = When the voltage VT is less than the reference voltage VBGR, the shutdown signal STP is at a logic low level, and the temperature of the wire circuit has not yet reached a specific temperature τ. The relationship between the debt voltage VT and the temperature can be determined according to the demand of n It is sufficient to apply temperature sensing resistors with different temperature coefficients. For a long time, it is worthwhile (4), 镰 reference electric surface (4) design side 2, t type, the present invention is not limited to the above-mentioned FIG. 1 and FIG. For example, ^ this gap reference voltage generator will produce a reference U that varies with the process variation. The current that the temperature sensing resistor turns on will change according to the internal current of the energy gap reference. _ Pressure, and the effect of the difference between the V process and the V process variation on the temperature sensing result. 曰, the above description uses the inner band of the bandgap reference voltage generator to detect the temperature change, due to the energy gap reference voltage generation The internal current of the #^W private is known to be dry; the core is self-contained, so the present invention can be compared with the way of detecting the temperature change by the solid current, the invention can offset the voltage of 16 201009309 · c / n The current variability greatly improves the accuracy and sensitivity of the temperature detection caused by the difference in the process. Although the present invention has been disclosed in the preferred embodiments as above, the invention is defined by the present invention, and any technical field of the invention has the usual Those skilled in the art will be able to make changes and refinements without departing from the spirit and scope of the present invention. The scope of the present invention is defined by the scope of the patent application.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a temperature detecting circuit according to a first embodiment of the present invention. 2 is a temperature detecting circuit in accordance with a second embodiment of the present invention. Fig. 3 is a diagram showing temperature detection waveforms according to the first embodiment and the second embodiment of the present invention. [Main component symbol description] 100, 200: Temperature detecting circuit 110, 210: Bandgap reference voltage generator 112: Bandgap reference circuit 114: Differential amplifier 120: Comparison module 130: Comparator

Rll〇. Temperature sensing resistor

Ru, R12, R13, R14: resistance

Pll~Pl7, P21~P22: PMOS transistor Νιι, N12, N13, Ν2ι, N22 : NMOS transistor

Bn, Bu, B13: PNP bipolar transistor 17 201009309 』934twf.doc/n 201009309 』934twf.doc/n Reference current Worker 1 ~ I5, work 21, I22,! 23 . VDD : Voltage source VT : Detection voltage VBGR : Reference voltage VI : First node voltage V2 : Second node voltage STTP : Stop signal DV : Differential voltage AV : Adjust voltage

18

Claims (1)

201009309 .-8934twf.doc/n X. Patent application scope: 1. A temperature detecting circuit comprising: a bandgap reference voltage generator for generating a reference voltage and a first reference current; and a comparison module And generating a detection voltage according to the first reference current, and comparing the reference voltage with the detection voltage to output a shutdown signal, wherein the shutdown signal corresponds to a specific temperature. 2. The temperature detecting circuit of claim 1, wherein the bandgap reference voltage generator comprises: a first current source for generating a second reference current; and a second current a source, a handle connected to the current source, and generating the first reference current according to the second reference current, wherein the bandgap reference voltage generator generates the reference voltage according to the second reference current. 3. The temperature detecting circuit of claim 2, wherein the comparing module comprises: φ a temperature sensing resistor coupled between the second current source and a ground, wherein the temperature sense And detecting, by the first common node of the second current source, the detection voltage; and a comparator coupled to the output of the bandgap reference voltage generator and the first common node for comparing the reference voltage And detecting the voltage to output the shutdown signal. 4. The temperature detecting circuit of claim 3, wherein the temperature sensing resistor has a positive temperature coefficient. 19 ^934twf.doc/n 201009309 5. The temperature detecting circuit according to claim 2, wherein the bandgap reference voltage generator further comprises a band gap reference circuit connected to the first current a source and a gate of the ground are used to generate a first node voltage and a second node voltage; and an operational amplifier is connected to the bandgap reference circuit and according to the first Lang voltage and the second node voltage Output—Adjust voltage to the first current source to adjust the second reference current. 6. The temperature side circuit according to claim 5, wherein the operational amplifier comprises: a second and a third current source coupled to the first current source, and generating a third reference according to the second reference current. Current; - difference 2 is amplified by H, _ between the third electrical surface and the ground terminal 'and according to the first node voltage and the second node electrical voltage; and the lee-output stage circuit, the voltage of the wire amplifier The hybrid voltage is output to the first, and the second current source is adjusted to adjust the second, first, and third reference currents. 7. The temperature-precision circuit as described in the patent _6, the output stage circuit includes: Dan A - PMOS t a preferred source of the PM () S transistor 'The gate of the PMOS transistor is coupled to the first - current =: two: a fourth reference current corresponding to the second reference current; and ', generating an NMOS transistor coupled between the pM 〇s and the ground terminal' and the touch 0S transistor The gate surface is connected to::: 20 201009309, J934twf.doc/n voltage, f, the PMOS transistor and a second common node of the NMOS transistor are coupled to the gate of the PMOS transistor, and the The second sharing node outputs the adjustment voltage. 8. The temperature detecting circuit of claim 1, wherein the bandgap voltage generator further comprises: a PMOS transistor coupled between a voltage source and a resistor, and φ a gate of the PMOS transistor is coupled to the first current source; and a bipolar transistor is coupled between the other end of the resistor and the ground, and a base of the bipolar transistor is coupled to the gate a ground terminal, wherein the resistor and the second common node of the PMOS transistor rotate the reference voltage. 9. The temperature detecting circuit of claim 8, wherein the bipolar transistor is a PNP bipolar transistor. 10. The temperature detecting circuit according to claim 5, wherein the energy gap reference circuit comprises: #四^第—resistance, secretive to the first current source and the first-dipolar electric crystal ground ί The other end of the first-bipolar transistor is connected to the base green, and the third-resistor is connected in series with the third resistor - between the first current source and its polarity transistor The other end of the second bipolar transistor is coupled to the ground, and the first resistor and the second bipolar transistor output the first node voltage. The second resistor and the second bipolar electrode 21 ▲ 3934 twf. doc / n 201009309 - the third common node, the ridge, the patent system, the garden system, the temperature system, the 制 - double Both the polar transistor and the second bipolar transistor are a PNP polar transistor. >12·Please refer to the temperature range of the second handle of the patent range, wherein the two current sources include a -pM〇 s transistor, the second current source package The first-PM〇S transistor ′ and the gates of the first PMOS transistor and the second PMOS transistor are mutually (four) 妾(10) into a current mirror. 13. The temperature detecting circuit of claim 2, wherein the bandgap reference voltage generator comprises: a first PMOS transistor coupled between a voltage source and a first transistor; a second PMOS transistor coupled between the voltage source and a second transistor, and the gate of the first PM〇s transistor without the second pM〇s transistor is coupled to each other to form the a first current source; a bipolar transistor is coupled between the other end of the first NMOS transistor and the ground, and a base of the first bipolar f crystal is connected to the ground; a resistor coupled between the second _08 transistor and a second bipolar transistor coupled between the other end of the first resistor and the ground terminal and the base of the second bipolar transistor The gate of the first PMOS transistor is coupled to a second common point of the first PMOS transistor and the first NM 〇s transistor, 22 201009309 ] 934 twfdoc / n the first NMOS transistor is electrically connected to the second singular (10), and the second NMOS transistor is connected The electrically common the third transistor and a second transistor of ^ 〇S outline point. 〇s Η. The temperature-gap reference voltage generator according to claim 13 further includes: a circuit, a gate of the transistor; and a body axis connected to the first (10) OS — The third bipolar transistor is lightly connected to the ground::, and the base of the bipolar transistor outputs the reference voltage with the node. In the fourth total, the f 13 _ _ _ circuit 'its crystal. And the two-polar crystals of the two brothers are - ΡΝΡ bipolar electric in the ^ circuit, its electro-crystal 髀 — - PM 〇 S transistor, the third PM 〇 S crystal • coupling two: between the module And the three sides of the electricity, the gate of a PMOS transistor. In the second item of (4), the first reference current is equal to the second reference current. twenty three