JPS6190511A - Semiconductor integrated circuit - Google Patents

Abstract

PURPOSE:To prevent malfunction of a circuit due to leakage current and defect by providing the 1st and 2nd p-n junction elements connected in series poled the same and connecting a signal path having an optional impedance to a common connecting point between the 1st and 2nd p-n junctions to compensate the leakage current of the p-n junction elements. CONSTITUTION:A leakage current flows to the 1st and 2nd junction capacitors respectively by a reverse bias potential, and each current is assumed to be the same by applying the same reverse bias potential to the capacitors and arranging closely the 1st and 2nd junction capacitors on one semiconductor circuit substrate so as to be nearly of the same area with the same structure. Thus, a leakage current IL1 flows from an input terminal to the 1st junction capacitor 7 in the grounding direction, a leakage current IL2 flows from the reference voltage circuit 8 to the 2nd junction capacitor 7 in the direction of the input terminal 7, the relation of IL1=IL2 is established and each leakage current to the 1st and 2nd junction capacitors is compensated by the mutual leakage current.

Description

[Detailed Description of the Invention] [Industrial Application Separation] The present invention is a semi-quadruple assembly [! In 2 circuits, I6 for bow)
Archery 51! Is it on the I8 route? The present invention relates to a semiconductor integrated circuit that compensates for leakage current of connected PN junction elements, prevents circuit malfunctions and defects caused by leakage current, and is easy to configure.

[Conventional technology]

Conventionally, junction capacitors using PN junction elements have been used for signal path AC coupling, filters, etc. in signal processing circuits in semiconductor integrated circuits. Figure 2 shows a conventional implementation of a signal processing circuit using a low-pass filter with junction valley elbow, and an amplifier circuit 1.
．． 6. Resistance 3. The output terminal 2 of the amplifier circuit 1 is composed of a PN junction capacitor 4 and a resistor 3. A common connection point between the resistor 3 and the junction capacitor 4 is connected to the input terminal 5 of the amplifier circuit 60, and a constant reverse bias potential is applied to the junction capacitor 4. It forms a low-pass filter with a constant cut-off wave number determined by the resistivity value of 3 and the capacitance value of junction volume 4. [Problems to be solved by the invention] Such conventional (b) roadside In this case, a leakage current due to the reverse bias voltage flows in the junction capacitor 4, but this leakage current cannot be ignored, especially when the junction area is large. There were drawbacks such as bias potential deviation and operational problems such as not responding when a small signal was input.

An object of the present invention is to provide a semiconductor integrated circuit in which leakage current of a PN fitting element in a signal processing circuit of a semiconductor integrated circuit is compensated for and operational defects caused by the leakage current are improved.

[Means for solving problems]

According to the invention, the signal path includes first and second PN junction elements connected in series in the same conductive direction, and has a unique impedance at a common connection point of the first and second PN junction elements. A semiconductor integrated circuit is obtained, in which the first and twentieth PN junction elements are connected to each other, and substantially equal reverse bias potentials are applied to each of the first and 20th PN junction elements.

〔Example〕

Next, the present invention will be explained in more detail with reference to the drawings.

FIG. 1 is a circuit diagram of an embodiment according to the present invention, and FIG.
Functional elements that are the same as those in the figures are given the same reference numerals.

The output terminal 2 of the amplifier circuit 1 is grounded via the resistor 3 and each first junction 4, and the common connection point between the resistor 3 and each first junction 4 is connected to the input terminal 5 of the RA width circuit 6. At the same time, the power terminal of the first and second junctions 7 is connected to the input terminal 5 so that the second junction valley ki7 is connected in series with the first junction capacitor in the direction of the same sensitive electric power. The other power terminal of the voltage 7 is connected to the reference voltage circuit 8, and the first terminal is connected to the reference voltage circuit 8. An equal reverse bias potential is applied to each of the second junctions, and their capacitance values are set to be the same.

In this implementation, the first. An IJ current of 17mm is applied to each of the second junction valley lids due to the reverse bias potential.
By arranging each of the bonded parts on the same semiconductor integrated circuit board in close proximity to each other so that they have the same structure and approximately the same area, the first. It can be assumed that equal leakage current flows through each of the second junction capacitances K.

Therefore, a leakage current It,1 flows in the direction of the grounding force from the input terminal 5 to the first junction capacitor 4, but at the same time, leakage current also flows from the reference voltage circuit 8 in the direction of the input terminal 50 in each of the second junctions 7. IL2 flows, which causes IL
l = It, 1, and the respective leakage currents of the first and second junction capacitances are compensated by mutual leakage currents, and apparently the junction capacitances are connected to the resistor 3 and the input terminal 5 of the amplifier circuit 60. The influence of leakage current does not appear in .

〔Effect of the invention〕

As described above, according to the present invention, the leakage current of the PN junction element connected to the signal path can be compensated for, the operational defects caused by the leakage current can be improved, and a semiconductor integrated circuit with an easy configuration can be realized. can be provided.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing an embodiment of the present invention, and FIG. 2 is a circuit diagram showing a conventional example. 1.6... Amplifier circuit, 2... Output terminal, 3... Resistor, 4.7... Junction awards, 5
...Input terminal, 8...Reference voltage circuit.

Claims (1)

[Claims] 1. A signal path comprising first and second PN junction elements connected in series in the same conductive direction, and having an arbitrary impedance at a common connection point of the first and second PN junctions. A semiconductor integrated circuit characterized in that: is connected to the semiconductor integrated circuit. 2. The semiconductor integrated circuit according to claim 1, wherein substantially equal reverse bias potentials are applied to each of the first and second PN junction elements.