JPH05327473A - Ill injector current supply circuit - Google Patents

Abstract

PURPOSE:To reduce the drop of voltage of a current supply circuit by amplifying a reference current by a current mirror circuit and generating an injector current. CONSTITUTION:A power supply circuit 10 serves as a current mirror circuit which consist mainly of the NPN type transistors TRQ6, Q8, etc. The bases of the TRQ6-Qn re connected with each other with their emitters also connected to each other. In such a constitution of the current mirror circuit, a reference current Iref is inverted and amplified into an inverted current. Then the current Iref supplied to the circuit 10 and the inverted circuit are jointed together and supplied to the IIL gate circuits 2, 3, etc., as an injector current Iinj. In this case, the current amplification factor is decided by the current driving ability ratio between the TRQ6 and the TRQ8-Qn. Then the current driving ability is decided by the sizes of the emitter areas of those TRs.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an IIL injector current supply circuit, and more particularly, to an improved circuit for supplying an injector current to an IIL gate circuit having an IIL gate structure which is a kind of bipolar IC structure. Regarding

[0002]

2. Description of the Related Art FIG. 2 shows an example of a conventional IIL injector current supply circuit. Here, 1 is a current supply circuit,
Reference numerals 2 and 3 are IIL gate circuits. IIL gate circuit 2
Is a NOT gate having an IIL gate structure and has the most basic configuration. Other IIL gate circuits are also configured by this combination of basic gate structures. The IIL structure has a high degree of integration.
A large number of gate circuits are provided.

Since the IIL gate circuit is a current-driven gate element, the current supply circuit 1 supplies the current necessary for the operation of a large number of IIL gate circuits 2 and 3 as the injector current Iinj. Usually, only one or two current supply circuits 1 are provided in the IC in order to improve the degree of integration of the IC. Therefore, the current value of the injector current Iinj is required to be about several mA to several tens mA. Moreover, it is necessary to be stable at a constant value as the sum of the drive currents required for each gate circuit.

Therefore, the conventional current supply circuit 1 has the logic I
Even in the manufacturing process of C, a constant current circuit having a small current value that is easy to manufacture is provided to temporarily generate a highly accurate reference current Iref of about several tens μA to several hundreds μA. Then, the reference current Iref is amplified by the transistors Q1 and Q2 connected in Darlington to generate an injector current Iinj. This injector current Iinj is transferred to the transistor Q1,
The injector current Iinj is stable because it is determined by the amplification factor according to the resistance ratio of the bias resistors R1 and R2 of Q2 and the reference current Iref is accurate. Therefore, the IIL gate circuits 2 and 3 can operate stably.

[0005]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention II
In the L injector current supply circuit, when the reference current is amplified to generate the injector current, the Darlington transistor circuit is used and the amplification factor is set by the bias resistor. Therefore, a voltage drop occurs at this resistor. On the other hand, there is a demand for lowering the power supply voltage of the IC from the viewpoints of measures against withstand voltage accompanying the improvement of the degree of integration of the IC and saving of battery power. The IIL-IC is no exception and must meet this requirement.

However, in the current supply circuit having the conventional configuration, there is a voltage drop across the resistor in addition to the voltage drop across the amplifying transistor, so that the voltage drop is large. Moreover, I
In order to operate the IL gate, the voltage to the IIL gate needs to be maintained above a certain value. If this goes on,
This is a problem because the demand for lowering the power supply voltage of the IC cannot be met. An object of the present invention is to solve the above-mentioned problems of the prior art, and to reduce the voltage that drops when the injector current is generated. II
It is to realize a supply circuit of L injector current.

[0007]

The structure of the injector current supply circuit for an IIL of the present invention which achieves the above object is to generate an injector current by amplifying a predetermined reference current and supply it to the IIL gate circuit. IIL
In the injector current supply circuit of, the current mirror circuit that receives the reference current that flows in as an input signal and generates an inversion current that is inverted and amplified by the reference current is output, and the sum of the reference current and the inversion current. Is output as the injector current.

Specifically, it comprises NPN type first and second transistors, the bases of the first and second transistors are connected to each other, and the emitters of the first and second transistors are connected to each other. A current mirror circuit is provided which receives the reference current flowing in as an input signal in the collector of the first transistor and receives the inverted current obtained by inverting and amplifying the reference current in the collector of the second transistor. A current is output as the injector current.

[0009]

In the IIL injector current supply circuit of the present invention having such a configuration, the current mirror circuit is used instead of the Darlington transistor when the injector current to be supplied to the IIL gate is generated. And
The reference current is inverted and amplified to generate an inverted current, and the sum of these currents is used as the injector current. Therefore, the bias resistor is unnecessary and the voltage drop due to the resistor does not occur. Therefore, the voltage drop in the current supply circuit can be small, and the IIL-IC can be operated even by the power supply voltage lower than that in the past by that much.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an IIL injector current supply circuit of the present invention will be described below. Figure 1
Is a concrete circuit diagram thereof, 10 is a current supply circuit,
Reference numerals 2 and 3 are IIL gate circuits. The IIL gate circuits 2 and 3 are NOT gates as a typical example of the conventional IIL gate structure.

The current supply circuit 10 is a current mirror circuit mainly composed of NPN type transistors Q6 and Q8. The bases of the transistors Q6 and Q8 to Qn are connected to each other, and the emitters thereof are also connected to each other. Transistor Q6 receives reference current Iref at its collector, and transistors Q8-Qn have their collectors connected to each other and cause an inversion current to flow from power supply Vcc. In the figure, only the transistors Q8 and Qn are shown as a representative, but in reality, a larger number of transistors are connected in parallel to increase the amplification capability.

[0012] And, these many transistor transistors Q
In order to supply a sufficient base current to 8 to Qn, in a normal current mirror, the collector and base of a transistor Q6, which are directly connected, are connected to the base and emitter of a transistor Q7, and the collector thereof is connected to the collectors of a transistor Q8 and the like. It The reference current Iref is inverted and amplified by such a current mirror circuit to generate an inverted current, and the reference current Iref flowing into the current supply circuit 10 is generated.
The ref and the reverse current are merged and supplied to the IIL gate circuits 2 and 3 as the injector current Iinj.

In this case, the current amplification factor is the transistor Q.
6 and the current driving capability of the transistors Q8 to Qn. Furthermore, this drive capability is determined by the size of the emitter area of these transistors. That is,
The amplification factor is determined by the emitter area ratio of the transistor. By the way, in the manufacturing process of a transistor such as an IC, a high accuracy of the area ratio of elements can be easily achieved. Therefore, since the reference current Iref is amplified with an accurate amplification factor to generate an accurate inversion current, the current value of the injector current Iinj which is the sum of these is also stable.

Moreover, in this case, the current mirror circuit does not require a bias resistor. Therefore, the voltage drop when the injector current Iinj is generated is only in the transistors Q7 and Q8. Therefore, even if the voltage value of the power supply Vcc is reduced by the voltage drop in the conventional resistor, the injector current Iinj having a sufficient current value for the IIL gate circuits 2 and 3 and the like.
Can be supplied.

[0015]

As can be understood from the above description, in the IIL injector current supply circuit of the present invention, the injector current is generated by amplifying the reference current by the current mirror circuit. As a result, the voltage drop in the current supply circuit can be small. As a result, there is an effect that it is possible to cope with a reduction in the voltage of the power supply.

[Brief description of drawings]

FIG. 1 is a circuit diagram of an embodiment of an IIL injector current supply circuit having the configuration of the present invention.

FIG. 2 is a circuit diagram of a conventional IIL injector current supply circuit.

[Explanation of symbols]

 1 current supply circuit 2, 3 IIL gate circuit 10 current supply circuit

Claims (1)

[Claims] 1. An injector current is generated by current amplification of a predetermined constant current and is supplied to an IIL gate circuit.
The injector current supply circuit for IL includes a current mirror circuit that receives the constant current that flows in as an input signal, generates a reverse current that is inverted and amplified by the constant current and outputs the constant current and the reverse current. An IIL injector current supply circuit, wherein a sum current is output as the injector current.