CN104484007A

CN104484007A - Current source for high-speed analog radio-frequency circuit

Info

Publication number: CN104484007A
Application number: CN201410659222.4A
Authority: CN
Inventors: 魏慧婷; 赵元富; 文武; 侯训平; 毕波; 荣欣; 张佃伟; 李永峰; 张娜娜; 刘璐; 段冲; 焦洋; 韩放
Original assignee: Beijing Microelectronic Technology Institute; Mxtronics Corp
Current assignee: Beijing Microelectronic Technology Institute; Mxtronics Corp
Priority date: 2014-11-18
Filing date: 2014-11-18
Publication date: 2015-04-01
Anticipated expiration: 2034-11-18
Also published as: CN104484007B

Abstract

The present invention is a current source for high-speed analog and radio frequency circuits, comprising a first current generation circuit, a second current generation circuit and a current synthesis circuit. The output current I0 of the first current generation circuit is a current that increases with the increase of temperature; the output current I4 of the second current generation circuit is a current source with adjustable temperature coefficient. When it is lower than a certain temperature threshold T0, the current I4 The temperature coefficient is controlled by resistor R4; and when it is higher than T0, the current I4 decreases to 0, and the temperature threshold T0 is controlled by resistor R3. The final current I _out of the output of the current synthesis circuit is obtained by adding the current I1 and the current I2, the current I1 is k1 times the first current I0, and I2 is k2 times the second current I4. By adjusting the values of resistors R3 and R4, and the coefficients k1 and k2, an output current with a controllable and variable temperature coefficient can be obtained, which can well meet the different requirements of high-speed analog and radio frequency circuit current bias.

Description

A Current Source for High Speed Analog and RF Circuits

技术领域technical field

本发明属于电流源电路设计技术领域，具体涉及一种用于高速模拟及射频电路的电流源。The invention belongs to the technical field of current source circuit design, in particular to a current source for high-speed analog and radio frequency circuits.

背景技术Background technique

传统的电流源主要有三类，即恒定电流源(电流不随温度变化)，正温度系数电流源和负温度系数电流源。这三种电流源的温度系数变化单一，电路设计受到一定的限制。尤其在高速模拟及射频电路应用中，比如高速预分频电路，其输入输出信号幅度范围和工作频率范围都受偏置电流的影响很大。若使用恒定电流源，在低温段电流能使电路正常工作，但在高温段，随着温度的升高，器件工作频率下降，需要更大的电流，显然恒定电流源不能满足要求；这种情况下若使用正温度系数电流源，则低温时电流将过小，器件将不能正常工作；同理，若使用负温度系数电流源，则高温时电流将过小。可见，传统的电流源很难完全满足高速电路的设计要求。There are three main types of traditional current sources, namely constant current source (current does not change with temperature), positive temperature coefficient current source and negative temperature coefficient current source. The temperature coefficients of these three current sources have a single change, and the circuit design is subject to certain restrictions. Especially in high-speed analog and RF circuit applications, such as high-speed prescaler circuits, the input and output signal amplitude range and operating frequency range are greatly affected by the bias current. If a constant current source is used, the current in the low temperature section can make the circuit work normally, but in the high temperature section, as the temperature increases, the operating frequency of the device decreases, and a larger current is required. Obviously, the constant current source cannot meet the requirements; in this case If a positive temperature coefficient current source is used, the current will be too small at low temperature, and the device will not work normally; similarly, if a negative temperature coefficient current source is used, the current will be too small at high temperature. It can be seen that the traditional current source is difficult to fully meet the design requirements of high-speed circuits.

发明内容Contents of the invention

本发明解决的技术问题是：克服现有技术的不足，提出了一种用于高速模拟及射频电路的电流源，使得低温下电流的温度系数可调，电流不会过小，高温下维持正温度系数特性，能同时满足高速模拟及射频电路在高低温下对电流源的需求。The technical problem solved by the present invention is: to overcome the deficiencies of the prior art, a current source for high-speed analog and radio frequency circuits is proposed, so that the temperature coefficient of the current at low temperature can be adjusted, the current will not be too small, and it can maintain positive current at high temperature. The temperature coefficient characteristics can meet the needs of high-speed analog and RF circuits for current sources at high and low temperatures.

本发明的技术方案是：一种用于高速模拟及射频电路的电流源，包括第一路电流产生电路、第二路电流产生电路和电流合成电路；The technical solution of the present invention is: a current source for high-speed analog and radio frequency circuits, including a first current generation circuit, a second current generation circuit and a current synthesis circuit;

所述第一路电流产生电路包括PMOS管P1、PMOS管P4、NPN管Q1和电阻R1；所述第二路电流产生电路包括PMOS管P7～PMOS管P12、NPN管Q3、NPN管Q4、电阻R3和电阻R4；所述电流合成电路包括PMOS管P2、PMOS管P3、PMOS管P5、PMOS管P6、NPN管Q2及电阻R2；The first current generating circuit includes PMOS transistor P1, PMOS transistor P4, NPN transistor Q1 and resistor R1; the second current generating circuit includes PMOS transistor P7 to PMOS transistor P12, NPN transistor Q3, NPN transistor Q4, resistor R3 and resistor R4; the current synthesis circuit includes PMOS transistor P2, PMOS transistor P3, PMOS transistor P5, PMOS transistor P6, NPN transistor Q2 and resistor R2;

PMOS管P1、PMOS管P2、PMOS管P3、PMOS管P6、PMOS管P7、PMOS管P9和PMOS管P11的源极均接至电源VDD；PMOS管P1的漏极接至PMOS管P4的源极，PMOS管P1的栅极同时接至PMOS管P4的漏极和PMOS管P2、PMOS管P7、PMOS管P11的栅极，PMOS管P2和PMOS管P3的漏极均接至PMOS管P5的源极，PMOS管P5的漏极作为电流源的输出端向外输出I_out；PMOS管P4、PMOS管P5、PMOS管P6、PMOS管P8、PMOS管P10、PMOS管P12的栅极均连接在一起后，一同接至PMOS管P6的漏极；PMOS管P7的漏极接至PMOS管P8的源极，PMOS管P9的漏极接至PMOS管P10的源极，PMOS管P9的栅极同时接至PMOS管P3的栅极和PMOS管P10的漏极，PMOS管P11的漏极接至PMOS管P12的源极；NPN管Q1的集电极接至PMOS管P4的漏极，NPN管Q1的发射极接至电阻R1的一端，NPN管Q1的基极与NPN管Q2的基极连接至外部基准电压VBG，NPN管Q2的集电极接PMOS管P6的漏极，NPN管Q2的发射极接电阻R2的一端，电阻R1和电阻R2的另一端均接地GND；NPN管Q3的集电极接至PMOS管P10的漏极，NPN管Q3的基极同时接至NPN管Q4的集电极和PMOS管P12的漏极，NPN管Q3的发射极同时接至NPN管Q4的基极和电阻R4的一端，电阻R4的另一端同时接电阻R3的一端和PMOS管P8的漏极，电阻R3的另一端和NPN管Q4的发射极均接地。The sources of PMOS transistor P1, PMOS transistor P2, PMOS transistor P3, PMOS transistor P6, PMOS transistor P7, PMOS transistor P9 and PMOS transistor P11 are connected to the power supply VDD; the drain of PMOS transistor P1 is connected to the source of PMOS transistor P4 , the gate of PMOS transistor P1 is connected to the drain of PMOS transistor P4 and the gates of PMOS transistor P2, PMOS transistor P7, and PMOS transistor P11 at the same time, and the drains of PMOS transistor P2 and PMOS transistor P3 are connected to the source of PMOS transistor P5 The drain of the PMOS transistor P5 is used as the output terminal of the current source to output I _out ; the gates of the PMOS transistor P4, the PMOS transistor P5, the PMOS transistor P6, the PMOS transistor P8, the PMOS transistor P10, and the PMOS transistor P12 are all connected together After that, they are connected to the drain of PMOS transistor P6; the drain of PMOS transistor P7 is connected to the source of PMOS transistor P8, the drain of PMOS transistor P9 is connected to the source of PMOS transistor P10, and the gate of PMOS transistor P9 is simultaneously connected to To the gate of PMOS transistor P3 and the drain of PMOS transistor P10, the drain of PMOS transistor P11 is connected to the source of PMOS transistor P12; the collector of NPN transistor Q1 is connected to the drain of PMOS transistor P4, and the emitter of NPN transistor Q1 The electrode is connected to one end of the resistor R1, the base of the NPN transistor Q1 and the base of the NPN transistor Q2 are connected to the external reference voltage VBG, the collector of the NPN transistor Q2 is connected to the drain of the PMOS transistor P6, and the emitter of the NPN transistor Q2 is connected to the resistor One end of R2, the other end of resistor R1 and resistor R2 are grounded to GND; the collector of NPN transistor Q3 is connected to the drain of PMOS transistor P10, and the base of NPN transistor Q3 is simultaneously connected to the collector of NPN transistor Q4 and PMOS transistor P12 The drain of NPN transistor Q3 is connected to the base of NPN transistor Q4 and one end of resistor R4 at the same time, the other end of resistor R4 is connected to one end of resistor R3 and the drain of PMOS transistor P8 at the same time, the other end of resistor R3 is connected to The emitters of the NPN transistor Q4 are all grounded.

电阻R1～电阻R4为恒温电阻或负温度系数电阻，且电阻R3和电阻R4为可变电阻。The resistors R1 to R4 are constant temperature resistors or negative temperature coefficient resistors, and the resistors R3 and R4 are variable resistors.

本发明与现有技术相比的优点在于：The advantage of the present invention compared with prior art is:

1、电流合成电路输出的最终电流I_out由第一路电流产生电路输出电流I0和第二路电流产生电路输出电流I4乘以比例系数k1、k2后相加得到。其中，电流I0为正温度系数电流；当低于某个温度阈值(T0)时，电流I4的温度系数由电阻R4控制；而当高于T0时，电流I4降低到0，温度阈值T0由电阻R3控制。1. The final current I _out output by the current synthesis circuit is obtained by multiplying the output current I0 of the first current generating circuit and the output current I4 of the second current generating circuit by the proportional coefficients k1 and k2 and then adding them together. Among them, the current I0 is a positive temperature coefficient current; when it is lower than a certain temperature threshold (T0), the temperature coefficient of the current I4 is controlled by the resistor R4; and when it is higher than T0, the current I4 is reduced to 0, and the temperature threshold T0 is controlled by the resistor R4 R3 control.

2、本发明所述的电流源电路通过调节可变电阻R3和R4的值，及系数k1和k2，可以得到温度系数可控可变的输出电流，使得低温下电流的温度系数可调，电流不会过小，高温下维持正温度系数特性，能同时满足高速模拟及射频电路在高低温下对电流源的不同需求。2. The current source circuit of the present invention can obtain an output current with a controllable and variable temperature coefficient by adjusting the values of the variable resistors R3 and R4, and the coefficients k1 and k2, so that the temperature coefficient of the current at low temperature is adjustable, and the current It will not be too small, maintain positive temperature coefficient characteristics at high temperatures, and can meet the different needs of high-speed analog and RF circuits for current sources at high and low temperatures.

附图说明Description of drawings

图1为本发明的一种用于高速模拟及射频电路的电流源的结构示意图；Fig. 1 is a kind of structural representation of the current source that is used for high-speed analog and radio frequency circuit of the present invention;

图2为电流I0和I4合成为输出电流I_out的一种温度特性曲线示意图；Fig. 2 is a schematic diagram of a temperature characteristic curve in which current I0 and I4 are synthesized into an output current _Iout ;

图3为改变电阻R4来改变I_out在-55℃～T0段电流温度系数的一种仿真示意图；Fig. 3 is a simulation schematic diagram of changing the current temperature coefficient of I _out at -55°C to T0 by changing the resistor R4;

图4为改变电阻R3来改变I_out温度阈值T0的一种仿真示意图。FIG. 4 is a simulation schematic diagram of changing the temperature threshold T0 of I _out by changing the resistor R3.

具体实施方式Detailed ways

本发明提出的一种用于高速模拟及射频电路的电流源，结合附图详细说明如下。A current source for high-speed analog and radio frequency circuits proposed by the present invention is described in detail as follows in conjunction with the accompanying drawings.

设PMOS管P1、P2、P3、P7、P9、P11上的电流分别为I0、I1、I2、I3、I4、I5，则PMOS管P1、P2、P7、P11上的电流成比例镜像关系，PMOS管P2上电流I1为PMOS管P1上电流I0的k1倍，PMOS管P7上电流I3为PMOS管P1上电流I0的k3倍。PMOS管P3、P9上的电流成比例镜像关系，PMOS管P3上电流I2为PMOS管P9上电流I4的k2倍，其中k1、k2、k3为1～10之间的正数。Assuming that the currents on the PMOS transistors P1, P2, P3, P7, P9, and P11 are I0, I1, I2, I3, I4, and I5 respectively, then the currents on the PMOS transistors P1, P2, P7, and P11 are in a proportional mirror relationship, and the PMOS The current I1 on the tube P2 is k1 times of the current I0 on the PMOS tube P1, and the current I3 on the PMOS tube P7 is k3 times of the current I0 on the PMOS tube P1. The currents on the PMOS transistors P3 and P9 are in a proportional mirror relationship, and the current I2 on the PMOS transistor P3 is k2 times the current I4 on the PMOS transistor P9, wherein k1, k2, and k3 are positive numbers between 1 and 10.

电流源由第一路电流产生电路(100)、第二路电流产生电路(200)和电流合成电路(300)三个部分组成。电流合成电路(300)的输出电流I_out即为最终输出的电流，该电流由PMOS管P2上电流I1和PMOS管P3上电流I2相加得到，其中电流I1为电流I0的k1倍，电流I2为电流I4的k2倍，可以得到输出电流I_out的表达式如下。The current source is composed of three parts: a first current generation circuit (100), a second current generation circuit (200) and a current synthesis circuit (300). The output current _Iout of the current synthesis circuit (300) is the final output current, which is obtained by adding the current I1 on the PMOS transistor P2 and the current I2 on the PMOS transistor P3, wherein the current I1 is k1 times the current I0, and the current I2 It is k2 times of the current I4, the expression of the output current I _out can be obtained as follows.

I_out＝k1*I0+k2*I4 (1)I _out =k1*I0+k2*I4 (1)

电流I0为随温度增加而增大的电流(PTAT电流)，由基准电压V_BG通过NPN管Q1和电阻R1产生。设NPN管Q1的基极和发射极之间的压差为V_BE1，则电流I0的表达式为：The current I0 is a current (PTAT current) that increases with temperature, and is generated by the reference voltage V _BG through the NPN transistor Q1 and the resistor R1. Assuming that the voltage difference between the base and the emitter of the NPN transistor Q1 is V _BE1 , the expression of the current I0 is:

$I I 00 = = \frac{{V V}_{BG BG} - - {V V}_{BE BE 11}}{R R 11} - - - - - - ((22))$

基准电压V_BG从外部输入，为与温度无关的电压，V_BE1为负温度系数的电压，这里设R1为恒温度系数的电阻，所以I0为正温度系数的电流。另外，对于R1为负温度系数的电阻，以上结论同样适用。The reference voltage V _BG is input from the outside and is a temperature-independent voltage. V _BE1 is a voltage with a negative temperature coefficient. Here, R1 is a resistor with a constant temperature coefficient, so I0 is a current with a positive temperature coefficient. In addition, the above conclusion is also applicable to the resistor with negative temperature coefficient of R1.

同样的，由基准电压V_BG通过NPN管Q2和电阻R2产生另一组正温度系数电流，该电流通过PMOS管P6镜像到P4、P5、P8、P10和P12，以保证电路正常工作。Similarly, another set of positive temperature coefficient current is generated by the reference voltage V _BG through the NPN transistor Q2 and the resistor R2, and the current is mirrored to P4, P5, P8, P10 and P12 through the PMOS transistor P6 to ensure the normal operation of the circuit.

设NPN管Q3发射极与Q4基极的交点为A点，R4一端与R3一端的交点为B点，设温度阈值为T0。Set the intersection of the emitter of NPN transistor Q3 and the base of Q4 as point A, the intersection of one end of R4 and one end of R3 as point B, and set the temperature threshold as T0.

当温度T<T0时，电流从A点流向B点，且Q4的基极电流可忽略不计，根据基尔霍夫定律，可计算出I4的表达式：When the temperature T<T0, the current flows from point A to point B, and the base current of Q4 is negligible. According to Kirchhoff's law, the expression of I4 can be calculated:

$I I 44 = = \frac{11}{R R 33 + + R R 44} * * [[{V V}_{BE BE 44} - - \frac{k k 33 * * R R 33}{R R 11} (({V V}_{BG BG} - - {V V}_{BE BE 11}))]] ((T T < < T T 00)) - - - - - - ((33))$

当温度T>T0时，电流由B点流向A点，此时NPN管Q3进入截止区，电流流向Q4管的基极。由于电流I4是由PMOS管P9上电流镜像得到的，而P9上的电流等于Q3上的电流，所以电流I4为0。When the temperature T>T0, the current flows from point B to point A. At this time, the NPN transistor Q3 enters the cut-off region, and the current flows to the base of the Q4 transistor. Since the current I4 is obtained by the current mirror on the PMOS transistor P9, and the current on P9 is equal to the current on Q3, the current I4 is 0.

设I4＝0，得出电阻R3的表达式为Assuming I4=0, the expression of resistance R3 is obtained as

$R R 33 = = \frac{R R 11}{k k 33} * * \frac{{V V}_{BE BE 44}}{{V V}_{BG BG} - - {V V}_{BE BE 11}} - - - - - - ((44))$

公知地，V_BE的表达式为Well known, the expression of V _BE is

${V V}_{BE BE} = = \frac{kT kT}{q q} ln ln \frac{{I I}_{c c}}{{I I}_{s the s}} - - - - - - ((55))$

这里可以将V_BE看成是与温度相关的函数，即为V_BE(T)，对于一个给定的温度T0，可以进一步得出R3的表达式为Here, V _BE can be regarded as a temperature-related function, that is, V _BE (T). For a given temperature T0, the expression of R3 can be further obtained as

$R R 33 = = \frac{R R 11}{k k 33} * * \frac{{V V}_{BE BE 44} ((T T 00))}{{V V}_{BG BG} - - {V V}_{BE BE 11} ((T T 00))} - - - - - - ((66))$

T0即为温度阈值，可根据电路需要设定一个温度T0，代入表达式就能确定R3的值。T0 is the temperature threshold. A temperature T0 can be set according to the needs of the circuit, and the value of R3 can be determined by substituting it into the expression.

当温度T<T0时，设R1、R3、R4为恒温度系数的电阻，对I4进行求导可得I4的温度系数为When the temperature T<T0, set R1, R3, R4 as resistances with constant temperature coefficients, and derivate I4 to get the temperature coefficient of I4 as

$\frac{&PartialD; &PartialD; I I 44}{&PartialD; &PartialD; T T} = = \frac{11}{((R R 33 + + R R 44))} * * ((\frac{{&PartialD; &PartialD; V V}_{BE BE 44}}{&PartialD; &PartialD; T T} + + \frac{k k 33 * * R R 33}{R R 11} * * \frac{{&PartialD; &PartialD; V V}_{BE BE 11}}{&PartialD; &PartialD; T T})) - - - - - - ((77))$

已知V_BE1和V_BE4为负温度系数的电压，故V_BE1和V_BE4对温度T求导为负数，由上式得出I4也为负温度系数电压。在设计时，R3由温度阈值T0决定，当R3确定后，改变R4的值就能调节I4的温度系数。对于R1、R3、R4为负温度系数的电阻时，结论类同，此处不再进行推导。It is known that V _BE1 and V _BE4 are voltages with negative temperature coefficients, so the derivatives of V _BE1 and V _BE4 to temperature T are negative numbers, and I4 is also a voltage with negative temperature coefficients from the above formula. When designing, R3 is determined by the temperature threshold T0. After R3 is determined, the temperature coefficient of I4 can be adjusted by changing the value of R4. When R1, R3, and R4 are resistors with negative temperature coefficients, the conclusions are similar, and the derivation will not be carried out here.

将式(2)和(3)代入式(1)可得Substituting equations (2) and (3) into equation (1), we can get

${I I}_{out out} = = k k 22 * * \frac{11}{R R 33 + + R R 44} * * {V V}_{BE BE 44} + + ((\frac{k k 11}{R R 11} - - k k 22 * * k k 33 * * \frac{R R 33}{R R 11 * * ((R R 33 + + R R 44))})) * * (({V V}_{BG BG} - - {V V}_{BE BE 11})) ((T T < < T T 00)) - - - - - - ((88))$

${I I}_{out out} = = k k 11 * * \frac{{V V}_{BG BG} - - {V V}_{BE BE 11}}{R R 11} ((T T > > T T 00)) - - - - - - ((99))$

由此可见，当T<T0时，Iout为温度系数可控可变的电流，通过调节可变电阻R3和R4的值，及系数k1和k2可以改变温度系数；当T>T0时，Iout为正温度系数电流。It can be seen that when T<T0, Iout is a current with a controllable and variable temperature coefficient, and the temperature coefficient can be changed by adjusting the values of variable resistors R3 and R4, and the coefficients k1 and k2; when T>T0, Iout is positive temperature coefficient current.

电流I0和I4合成为输出电流I_out的一种温度特性曲线如图2所示，其中横轴为温度，单位为摄氏度(℃)，温度范围为-55～125℃，纵轴为电流，单位为微安(uA)。该图由上下两组曲线组成，上面一组曲线分别为电流I0和I4随温度的变化图，下面的曲线为输出电流I_out随温度的变化图，可以看到图2情况下的温度阈值为T0＝50℃，The current I0 and I4 are synthesized into a temperature characteristic curve of the output current I _out as shown in Figure 2, where the horizontal axis is temperature, the unit is Celsius (°C), the temperature range is -55 to 125°C, and the vertical axis is current, the unit is is microampere (uA). The figure is composed of two sets of curves. The upper set of curves is the variation diagram of current I0 and I4 with temperature, and the lower curve is the variation diagram of output current I _out with temperature. It can be seen that the temperature threshold in the case of Figure 2 is T0 = 50°C,

改变电阻R4来改变输出电流I_out在-55℃～T0段电流温度系数的一种仿真示意图如图3所示，其中横轴为温度，单位为摄氏度(℃)，温度范围为-55～125℃，纵轴为电流，单位为微安(uA)。设电阻R3为一固定值，从上到下的三条输出电流I_out曲线对应三个不同的电阻值R4，并且I_out电流系数在-55℃～T0改变，这里温度阈值T0＝50℃。A schematic diagram of a simulation of changing the temperature coefficient of the output current I _out in the range of -55°C to T0 by changing the resistor R4 is shown in Figure 3, where the horizontal axis is the temperature, the unit is Celsius (°C), and the temperature range is -55 to 125 ℃, the vertical axis is the current, the unit is microampere (uA). Assuming that the resistor R3 is a fixed value, the three output current I _out curves from top to bottom correspond to three different resistance values R4, and the I _out current coefficient changes from -55°C to T0, where the temperature threshold T0=50°C.

改变电阻R3来改变输出电流I_out的温度阈值T0一种的仿真示意图如图4所示，其中横轴为温度，单位为摄氏度(℃)，温度范围为-55～125℃，纵轴为电流，单位为微安(uA)。设电阻R4为一固定值，从下到上的三条输出电流I_out曲线对应三个不同的电阻值R3，且对应三个不同的温度阈值T0，分别为50℃，70℃，90℃。A simulation schematic diagram of changing the temperature threshold T0 of the output current I _out by changing the resistor R3 is shown in Figure 4, where the horizontal axis is temperature, the unit is Celsius (°C), the temperature range is -55 to 125°C, and the vertical axis is current , the unit is microampere (uA). Assuming that the resistor R4 is a fixed value, the three output current I _out curves from bottom to top correspond to three different resistance values R3, and correspond to three different temperature thresholds T0, which are 50°C, 70°C, and 90°C respectively.

以上图2到图4三个图只是本电路功能的仿真示意图，图2和图3的温度阈值T0可以根据实际需要选取-55℃～125℃内的其它值。The above three figures from Figure 2 to Figure 4 are only the simulation diagrams of the circuit functions, and the temperature threshold T0 in Figure 2 and Figure 3 can be selected from other values within -55°C to 125°C according to actual needs.

本发明说明书中未作详细描述的内容属本领域专业技术人员的公知技术。虽然结合附图描述了本发明的实施方式，但是本领域普通技术人员可以在所附权利要求的范围内做出各种变形或修改。The content that is not described in detail in the description of the present invention belongs to the well-known technology of those skilled in the art. Although the embodiments of the present invention have been described with reference to the accompanying drawings, various variations or modifications may be made by those skilled in the art within the scope of the appended claims.

Claims

1., for a current source for High Speed Analog and radio circuit, it is characterized in that: comprise first via current generating circuit (100), the second road current generating circuit (200) and electric current combiner circuit (300);

Described first via current generating circuit (100) comprises PMOS P1, PMOS P4, NPN pipe Q1 and resistance R1; Described second road current generating circuit (200) comprises PMOS P7 ~ PMOS P12, NPN pipe Q3, NPN pipe Q4, resistance R3 and resistance R4; Described electric current combiner circuit (300) comprises PMOS P2, PMOS P3, PMOS P5, PMOS P6, NPN pipe Q2 and resistance R2;

The source electrode of PMOS P1, PMOS P2, PMOS P3, PMOS P6, PMOS P7, PMOS P9 and PMOS P11 is all connected to power vd D; The drain electrode of PMOS P1 is connected to the source electrode of PMOS P4, the grid of PMOS P1 is connected to the grid of the drain electrode of PMOS P4 and PMOS P2, PMOS P7, PMOS P11 simultaneously, the drain electrode of PMOS P2 and PMOS P3 is all connected to the source electrode of PMOS P5, and the drain electrode of PMOS P5 outwards exports I as the output terminal of current source _out; After the grid of PMOS P4, PMOS P5, PMOS P6, PMOS P8, PMOS P10, PMOS P12 all links together, be together connected to the drain electrode of PMOS P6; The drain electrode of PMOS P7 is connected to the source electrode of PMOS P8, and the drain electrode of PMOS P9 is connected to the source electrode of PMOS P10, and the grid of PMOS P9 is connected to the grid of PMOS P3 and the drain electrode of PMOS P10 simultaneously, and the drain electrode of PMOS P11 is connected to the source electrode of PMOS P12; The collector of NPN pipe Q1 is connected to the drain electrode of PMOS P4, and the emitter of NPN pipe Q1 is connected to one end of resistance R1, and the base stage of NPN pipe Q1 and the base stage of NPN pipe Q2 are connected to external reference voltages V _bG, the collector of NPN pipe Q2 connects the drain electrode of PMOS P6, one end of the emitter connecting resistance R2 of NPN pipe Q2, the equal ground connection GND of the other end of resistance R1 and resistance R2; The collector of NPN pipe Q3 is connected to the drain electrode of PMOS P10, the base stage of NPN pipe Q3 is connected to the collector of NPN pipe Q4 and the drain electrode of PMOS P12 simultaneously, the emitter of NPN pipe Q3 is connected to the base stage of NPN pipe Q4 and one end of resistance R4 simultaneously, other end one end of connecting resistance R3 and drain electrode, the other end of resistance R3 and the equal ground connection of emitter of NPN pipe Q4 of PMOS P8 simultaneously of resistance R4.

2. a kind of current source for High Speed Analog and radio circuit according to claim 1, it is characterized in that: resistance R1 ~ resistance R4 is constant temperature resistance or negative temperature coefficient resister, and resistance R3 and resistance R4 is variable resistor.