JPH01237708A - Semiconductor device - Google Patents

Abstract

PURPOSE:To stabilize a semiconductor device to the fluctuation of a power source voltage, to fluctuate a current, which flows in an output side, to temperature fluctuation and to arbitrarily set a reference voltage with satisfactory accuracy by using a constant voltage source to utilize the band gap of the semiconductor device which is used for a semiconductor integrated circuit, etc. CONSTITUTION:A constant voltage circuit 7 to utilize the band gap of the semiconductor device is composed of a capacitor C for oscillation prevention, PNP transistors TrQ1 and TrQ2, NPN TrQ3-Q7 and resistors R1-R6 and a power source voltage VCC from a voltage source 1 is caused to be a low voltage and outputted to an output terminal 4. Then, a reference voltage Vref is outputted to a reference voltage terminal 6. An emitter area is adjusted so that the current density of the emitter parts of the TrQ6 and Q7 can be same and the voltage of both edges due to the current to flow to the resistor R5 is made constant according to the temperature changed. Then, regardless of the fluctuation of the power source voltage and temperature, the reference voltage Vref is arbitrarily set.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a semiconductor device used in a semiconductor integrated circuit or the like.

[Conventional technology]

FIG. 4 is a circuit diagram of a semiconductor device regarding a reference voltage when a conventional constant current source is used. In the figure, (11 is a voltage source, 12!c power supply voltage V(!Q, )31 is G N
D, +41 is the output terminal VOUT1. (Qj)
, (Q9) are npn transistors, (R5), (R7)
, (R8) is a resistance.

Next, the operation will be explained. npn ) transistor (Q
8), the voltage between the base and emitter of (Q9) is V.
BP6. VBK9, resistance (R9), (R8)
, the current flowing through (R5) is
When the reverse saturation current of npn transistors (Q, 8) and (Q9) is denoted by e, then F and f8 become as follows. However, VT --, q is an electric elementary vagueness, R is Portzmann's constant, and Ti Kelvin temperature. Assuming that hlrE of the npn transistor (Q, 9) is sufficiently large,
It becomes Ia-15. Therefore, the voltage V between Vcc and VL)σT becomes V=R5φ6. Also, the formula 0 becomes approximately.

[Problem to be solved by the invention]

Conventional semiconductor device I! 1 is configured as above, so when a small reference voltage such as 0.1 V from the ms voltage Mac is required, the conventional method does not output accurately against power supply voltage changes and temperature fluctuations. Therefore, there were nine questions regarding the degree of species.

This invention was made in order to solve the above-mentioned problems, and its purpose is to obtain a semiconductor device that can obtain a reference voltage that can be arbitrarily set to a wide variety of degrees regardless of power supply voltage fluctuations and temperature fluctuations. do.

[Means to solve problems]

The rc semiconductor device of the present invention uses a constant voltage source that utilizes a conventional band gap to stabilize against fluctuations in power supply voltage, and also to vary the current flowing to the output side against fluctuations of m degrees. From VC, vcc, v
It is a highly stabilized version of our'r 1sJ1x8E.

[Function] By using a constant voltage source using a band gap, the semiconductor device according to the present invention can operate stably against power supply voltage fluctuations and temperature fluctuations.

〔Example〕

Hereinafter, one embodiment of the present invention will be explained. 1st
The figure is a circuit diagram of a semiconductor device. In the figure, ... is a voltage source, (21 is tsttvcct at GND, 141
is the output terminal (VOUT1, +51,161 is the reference voltage terminal (Vr@f), (71 is the constant voltage circuit using the conventional band gap (q is the rooting prevention capacitor, (Q
l+, (Q2) is I)! 1pl' transistor, (Q
3) ~ (Q,'F) are npn transistor% (R
6) to (R6) are resistances.

Next, the operation will be explained. npn) transistor (Q6
), (Q?) so that the current densities in the emitter parts of
61 is the same reference voltage Vr@t as the reference voltage terminal 151. Also, the resistor (R5) and the resistor (R6) are of the same type.

Here, the temperature Ta W 2! Let the resistance values of resistance (R5) and resistance (R6) at i°C (room temperature) be R5 and R6,
Voltage f Vl applied across resistor (R5), current flowing through (R5)? Vl-R5-engine=-a 7ref ------
−−１−−−■vl ” VC!cVOut
−−−−−−−−−−−■ becomes. Next vc 6 degrees'
The voltage applied across the resistor (R5) when ra changes by ΔTK is 72. When the temperature coefficient of resistance is rα, the resistance (R5
), and the resistance value of the resistor (R6) is R5(1+α
ΔT), R6 (1+αJT), and v2 becomes. Therefore, from ■ and ■, the voltage V applied across the resistor (R5) is V! Vi +=w V, which is constant, has a constant head against temperature fluctuations.

In addition, regarding fluctuations in the power supply voltage Vcc 121, since a voltage source using a conventional band gap is used, Vcc
ref becomes constant and voltage V becomes constant.

Incidentally, FIG. 2 is a circuit diagram showing another embodiment according to the present invention. The difference from the embodiment in FIG. 1 is that the reference voltage is from the power supply voltage Vcc Ill, whereas G N D 1
It starts from 31. In other words, the current mirror circuit is formed from the collector of the npn transistor (Q7).
np) A resistor (R5) is connected to GND+sl after removing the transistor (QIO) and (Q, ll).

By adopting such a configuration, the same effects as the above-mentioned implementation row can be achieved.

Moreover, the structure shown in FIG. 3 can also be used as a bias source related to the temperature coefficient of resistance.

〔Effect of the invention〕

As described above, since the VC of the present invention is constructed using a constant voltage source using a band gap, the VC accuracy is independent of power supply voltage fluctuations and temperature fluctuations (the reference voltage VOUT can be set arbitrarily).

[Brief explanation of the drawing]

Is Figure 1 an example of this invention? 2 and 8 are circuit diagrams of a semiconductor device showing another embodiment gA1 of the present invention, and FIG. 4 is a circuit diagram showing a conventional semiconductor device. In the figure, Il+ is the voltage source % (21 is the source voltage VQC
%・3) is GND, 141 is the output terminal (VOTTt)
, +51 + 161 is the base voltage terminal (Vref),
+71 is a voltage circuit, +c) is a tri prevention capacitor, (q, 2), (Qxo), (Qxx). (Ql2) is a pnp transistor, (Q3)l(Q4)
I(Q5)l(Ql, (Qt), (Qx3), (ci,
x4), (Qla) is npn) transistor, (R1
>, (R2)r(R3), (R4n, (R5), (R
6) is resistance. In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] The base of the current supply part of the constant voltage source using a bandgap is connected to the base of the first transistor, and the first resistor for setting an arbitrary reference voltage is connected between the emitter of the first transistor and GND. A semiconductor device characterized by a circuit configuration in which a second resistor is connected between the collector of the first transistor and a power supply voltage.