CN105808855A - InP heterojunction bipolar transistor circuit based on diode compensation - Google Patents

Abstract

The present invention discloses an InP heterojunction bipolar transistor circuit based on diode compensation. The InP heterojunction bipolar transistor circuit comprises a power unit module (1) and a current compensation module (2). The current compensation module is connected to an input end of the power unit module, so as to control an input current of the power unit module; the power unit module consists of a first Indium Phosphide heterojunction bipolar transistor Q1, and current compensation module consists of a second Indium Phosphide heterojunction bipolar transistor Q2 and a resistance R; and a collector of Q2 is short-connected to a base and, as a diode, connected to a base of Q1, and the resistance R is used as a control switch and connected between an emitter of Q2 and the ground. According to the InP heterojunction bipolar transistor circuit based on diode compensaiton, which is disclosed by the present invention, the self-heating effect of the InP heterojunction bipolar transistor is compensated at the cost of quite a few chip area according to a negative feedback compensation principle, so that direct current operating points are stabilized, linearity of transistor outputting is improved, and the circuit can be used for guiding direct current bias design of radio-frequency and microwave circuits.

Description

InP heterojunction bipolar transistor circuit based on diode compensation

Technical field

The invention belongs to technical field of circuit design, particularly to a kind of InP heterojunction bipolar transistor circuit based on diode compensation, the self-heating effect of InP heterojunction bipolar transistor can be improved, for instructing the direct current biasing of radio frequency and microwave circuit to design.

Background technology

Heterojunction of indium phosphide bipolar transistor InPHBT has the frequency characteristic of superelevation, bigger power density and the good linearity, is widely used in the circuit of microwave and millimeter wave and higher frequency.But, the high power density of InPHBT is easily caused the operating temperature of device and circuit and constantly raises.The device junction temperature increased can directly affect the electric property of device, increases the weight of self-heating effect, causes component failure, affects circuit reliability.Therefore, the self-heating effect improving InPHBT is significant for improving circuit stability.

For being operated in the InPHBT of forward amplification region, self-heating effect and it is on the impact of device electrology characteristic such as shown in expressions below:

T_j=T_A+R_thV_CEI_C

$I_C=I_S\exp \{\frac{q}{{\mathrm{\η\κT}}_A}\[V_{BE}+\mathrm{\φ}(T_j-T_A)\]\}$

$\mathrm{\φ}=-\frac{\∂V_{BE}}{\∂T}|I_C=const$

$\mathrm{\β}=\frac{\mathrm{\β}0}{1-\frac{V_{CE}}{V_A}}\exp \[\frac{\mathrm{\φ}(T_j-T_A)}{V_T}\]$

Wherein, T_jFor device junction temperature, T_AFor ambient temperature, R_thFor transistor thermal resistance, V_CEFor collector voltage, I_CFor collector current, I_SFor reverse saturation current, η is ideal factor, and κ is Boltzmann constant, V_BEFor emitter junction voltage, φ is thermal-electrical feedback coefficient, and β is device current gain, V_AFor the Early voltage of device, V_TFor thermal voltage.

By above formula it can be seen that device junction temperature T_jAlong with V_CEIncrease and increase.It is I for base bias current_BInPHBT, work as I_BTime less, I_CLess, T_jIncrease inconspicuous, by T_jThe I that change causes_C、V_BEVarying less, direct current biasing point is stable, and therefore self-heating effect can be ignored.Work as I_BTime bigger, I_CRelatively big, along with V_CEIncrease, device junction temperature T_jDramatically increasing, self-heating effect is obvious, collector current I_CAnd device current gain beta raises with device junction temperature and reduces, causing direct current biasing point unstable, that causes that transistor exports is non-linear.

In the design of large signal circuit, the linearity and stability are most important, and particularly with InPHBT, it increasingly focuses on the reliability of circuit in the application of Aero-Space and military field.Accordingly, it would be desirable to adopt process means or reach to suppress the purpose of the self-heating effect of InPHBT by the design of circuit structure, with the reliability of boost device and circuit.

At present, InPHBT is mainly optimized design from technological angle by the approach alleviating self-heating effect.Such as, by using the InP Asia colelctor electrode of the n+ of ion implanting to replace traditional InGaAs Asia colelctor electrode, the thermal resistance of InPHBT is reduced；Use Ballasting resistance to reduce device thermal resistance, carry out domination set electrode current by degenerative principle and alleviate the self-heating effect impact on device.But these methods can increase the complexity of HBT preparation technology mostly, chip area is significantly increased or the scope of application has limitation.

Summary of the invention

Present invention aims to the deficiency of above-mentioned prior art, a kind of InP heterojunction bipolar transistor circuit based on diode compensation is proposed, when being intended to the complexity not increasing HBT preparation technology, remove to improve the self-heating effect of InPHBT from the angle of circuit structure design.

For achieving the above object, the present invention includes power unit module, and this power unit module adopts an InP heterojunction bipolar transistor Q1 composition, it is characterised in that, input at power unit module is connected to current compensation module, for controlling the input current size of power unit module；

Described current compensation module, it is made up of a 2nd InP heterojunction bipolar transistor Q2 and resistance R, and the colelctor electrode of Q2 and base stage are shorted together, it is connected with the base stage of Q1 as diode, resistance R is as controlling switch, and its one end connects the emitter stage of Q2, other end ground connection.

The present invention compared with prior art, has the advantage that

Due to the fact that the input at power unit module connects current compensation module, according to degenerative principle, current compensation module can being equivalent to one by switching the nonlinear resistance being connected with power unit module, the disconnection of switch closes by total base stage input current I_BControlling, the size of nonlinear resistance is by the C-E junction voltage V of InPHBT power tube Q1_CEBeing controlled, therefore this nonlinear resistance is used for controlling InPHBT power tube Q1 base stage input current I_B1Size, by control I_B1Regulate the collector current I of InPHBT power tube Q1_C, it is ensured that overall current gain can remain stable within the specific limits, thus realizing the improvement to InPHBT self-heating effect；

Circuit provided by the invention compensate for the self-heating effect of InPHBT to sacrifice less chip area and power gain for cost, and compared with conventional art, the present invention does not increase the complexity of HBT preparation technology, has the scope of application widely.

Accompanying drawing explanation

Fig. 1 is the circuit theory diagrams of the present invention；

Fig. 2 is the output characteristic curve figure of the present invention；

Fig. 3 is the output characteristic curve figure of existing InP heterojunction bipolar transistor.

Detailed description of the invention

Understandable for enabling the above-mentioned purpose of the present invention, feature and advantage to become apparent from, below in conjunction with accompanying drawing, the specific embodiment of the present invention and effect are described in detail.

Referring to Fig. 1, the present invention includes: power unit module 1 and current compensation module 2；Current compensation module 2 is connected to the input of power unit module 1, for controlling the input current of power unit module 1；Wherein, power unit module 1 is made up of indium phosphide the first heterojunction bipolar transistor Q1；Current compensation module 2 is made up of indium phosphide the second heterojunction bipolar transistor Q2 and resistance R.

Described indium phosphide the first heterojunction bipolar transistor Q1, its base stage is connected with input IN, and its colelctor electrode connects outfan OUT, grounded emitter；

The colelctor electrode of described indium phosphide the second heterojunction bipolar transistor Q2 and base stage are shorted together, and are connected with the base stage of Q1 as diode, and resistance R is as controlling switch, and its one end is connected to the emitter stage of Q2, other end ground connection.

The operation principle of the present invention is as follows.

Total base stage input current I_BEnter from input IN, flow into power unit module 1 and 2 two branch roads of current compensation module.Along with total base stage input current I_BChange, as diode Q2 by control current compensation module 2 input resistance, regulate total base stage input current I_BDistribution condition between two branch roads, the base current I to Q1_B1Compensate.As total base stage input current I_BTime less, current compensation module 2 does not work, the base current I of indium phosphide the first heterojunction bipolar transistor Q1_B1Less and be basically unchanged, along with Q1 collector-emitter voltage V_CEIncrease, the collector current I of Q1_CRemaining unchanged, self-heating effect can be ignored, and overall current gain remains stable for；As total base stage input current I_BTime bigger, along with V_CEIncrease, the collector current gain of Q1 declines, and current compensation module 2 works, total base stage input current I_BRedistribute between Q1 and Q2, the base current I of Q1_B1Increase.So, although the current gain of Q1 reduces, but due to the base current I of Q1_B1Increase, the therefore collector current I of Q1_CNot reducing too many, overall current gain remains stable for so that circuit of the present invention can be operated under bigger operating current, reaches to improve the purpose of InPHBT self-heating effect.

The effect of the present invention can be further illustrated by following simulated properties curve chart:

Emulation 1, carries out output characteristics emulation to existing InP heterojunction bipolar transistor, and result is Fig. 3 such as.

Emulation 2, carries out output characteristics emulation to circuit of the present invention, and result is Fig. 2 such as.

Fig. 3 shows, as base current I_BTime bigger, the collector current of existing InP heterojunction bipolar transistor is along with V_CEIncrease be remarkably decreased, occur in that comparatively serious self-heating effect.

And it can be observed from fig. 2 that total base stage input current I_BTime bigger, the collector current I of Q1_CWith V_CEIncrease be held essentially constant, the operating point of circuit remains stable, illustrates, after invention increases current compensation module, the self-heating effect of InP heterojunction bipolar transistor is had obvious inhibition.

The above is the preferred embodiments of the invention, is not limited to the present invention, and for a person skilled in the art, the present invention can have various modifications and variations.All within the spirit and principles in the present invention, any amendment of making, equivalent replacement, improvement etc., all should include within protection scope of the present invention.

Claims (2)

1. the InP heterojunction bipolar transistor circuit based on diode compensation, including power unit module (1), this power unit module (1) adopts an InP heterojunction bipolar transistor Q1 composition, it is characterized in that, input at power unit module (1) is connected to current compensation module (2), is used for controlling the input current size of power unit module (1)；

Described current compensation module (2), it is made up of a 2nd InP heterojunction bipolar transistor Q2 and resistance R, and the colelctor electrode of Q2 and base stage are shorted together, it is connected with the base stage of Q1 as diode, resistance R is as controlling switch, and its one end connects the emitter stage of Q2, other end ground connection.

2. circuit according to claim 1, it is characterised in that an InP heterojunction bipolar transistor Q1, its base stage connects input bias current, and colelctor electrode is as outfan, grounded emitter.