JPS62130367A - Electronic device driving circuit - Google Patents

Abstract

PURPOSE:To reduce the waveform distortion of a pin output signal by mounting >=2 relays among plural relays of an electronic device on a module independent of a circuit board and providing necessary wiring. CONSTITUTION:Read relays R1-R4 are mounted on the module 16 independent of the circuit board and wired mutually in the module 16. This module 15 is mounted on the circuit board, but only oneside terminal pins P1-P4 of the relays R1-R4 are inserted into through holes of the circuit board at this time and the remaining terminal pins are not inserted into through holes. Thus, the number of terminal pins inserted into through holes is decreased, so the stray capacity is reduced correspondingly. Further, the relay R4 is added, but when input/output pins need not be connected to circuits of relays R5-Rn, the relay R4 is opened to disconnect the circuits of the relays R5-Rn from the input/output pins, thereby reducing the stray capacity which operates as a long on the input/output pins.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a testing apparatus for electronic devices such as (1)C, and more particularly to an electronic device drive circuit in an electronic device testing apparatus.

[Prior Art] An electronic device drive circuit of an electronic device inspection apparatus is -.
In general, each pin of the electronic device is provided with a plurality of relays (usually reed relays) for switching connections between pins of the electronic device to be tested and drivers, comparators, etc. (for example, 10 relays).

Conventionally, such relays are mounted directly on a circuit board of an electronic device driving circuit, and the terminal pins of the relay are routed through through-holes and surface patterns of the circuit board.

[Problem to be solved] In conventional electronic device drive circuits, the relay was mounted and the wiring structure was as described above, so the stray capacitance of the relay and its wiring was large, and the pin output signal of the electronic device was There was a problem with severe waveform distortion.

Furthermore, since the relays have to be arranged in a plane on one circuit board, there is also the problem that the mounting space is relatively large.

[Objective of the Invention] The first object of the present invention is to solve the problems described in There is something to look at.

[Means for Solving the Problems] To achieve this object, the present invention provides an electronic device drive circuit of an electronic device testing apparatus, in which at least a plurality of relays for switching connections between pins of the electronic device and a driver, etc. The seven components on two sides are mounted on a module independent from the circuit board of the electronic device drive circuit, the necessary wiring is made, and the module is mounted on the circuit board.

[Operation] Relays mounted on a module are not subject to any restrictions on their placement, so it is possible to arrange and wire them so that their stray capacitance is minimized.

Further, in order to mount the module, its terminal pin is inserted into a through hole of a circuit board, and what is connected to the module terminal pin is an r pin at one end of a part of the relay. In other words, the number of relay terminal pins inserted into the through holes is reduced compared to the case where all the relays are directly mounted on the circuit board. Through-hole l'2 clearance 1i)
is quite large, so a reduction in the number of r/bins at one end of the relay greatly contributes to a reduction in stray capacitance.

Thus, stray capacitance in the relay circuit portion of the electronic device drive circuit is reduced, and waveform distortion of the output signal at the pin of the electronic device is reduced.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic circuit diagram showing one embodiment of an electronic device driving circuit according to the present invention. A large number of similar electronic device drive circuits are provided in a portion called a test head of an electronic device testing apparatus, corresponding to the pins of the electronic device to be tested, but only one pin is shown in this figure.

In FIG. 1, a driver 10 applies a driving voltage to a specific input/output pin of the electronic device DV to be tested when driving the electronic device DV. Comparators 12 and 14 perform level comparison to check the normality of the human output signals.

R1-Rn are board relays for connecting and switching the human output pin of the electronic device DV to the driver IO, comparators 12, 14, etc. Here, reed relay R4
is not provided conventionally, and is added in this embodiment.

Conventionally, such reed relays for connection switching are mounted directly on the circuit board of the electronic device drive circuit, and all the terminal pins of the reed relays are inserted into through-holes on the circuit board, and the total floating due to the through-holes is The capacity was quite large.

Furthermore, since the reed relays had to be arranged in a plane, the wiring became quite long, and the stray capacitance caused by the wiring was also quite large. As a result, there was a problem in that the stray capacitance in the reed relay circuit portion was quite large, and the output signal of the electronic device was considerably distorted.

On the other hand, in this embodiment, reed relay R1
, R2, R3, and R4 are mounted on a module 16 independent from the circuit board, and interconnected within the module 16. Since the reed relays R1 to R4 have a higher degree of freedom in arrangement than when directly mounted on a circuit board, they can be arranged within the module 16 so that the stray capacitance of the wiring is minimized.

This module 16 is mounted on a circuit board. At that time, the terminal pins PL and P on one side of reed relays R1, R2, R3, and R4 are inserted into the through holes of the circuit board.
2. P3. P4 (or the module terminal pin connected to it); the remaining terminal pins are not inserted into the through holes.

In this way, since the number of terminal pins inserted into the through holes is reduced, stray capacitance is reduced accordingly.

Since the stray capacitance of the through hole is quite large, the effect of reducing the electrostatic field fit is large.

As described above, according to this embodiment, the stray capacitance of the connection switching reed relay and the wiring can be reduced to a considerable extent compared to the equivalent conventional electronic device drive circuit.

Further, in this embodiment, a reed relay R4 is added, and its effect on L1 will be explained. Conventionally, a relay such as reed relay R4 was not provided, so the circuits of reed relays R5 to Rn were always connected to the input/output pins of the electronic device DV, and the stray capacitance of the circuits of these reed relays was the load on the input/output pins. It was acting as.

In this embodiment, when it is not necessary to connect the input/output pins to the circuits of reed relays R5 to Rn, opening the reed relay R4 disconnects the circuits of those relays R5 to Rn from the input/output pins, and Stray capacitance that acts as a load on the pin can be reduced.

In this embodiment, the connection switching relay is a reed relay, but the type of the relay is not limited thereto.

Further, in this embodiment, only four of the connection switching relays are modularized, but it is also effective to modularize as many relays as α on two sides. However, the effect of reducing stray capacitance tends to increase as the number of modularized relays increases.

[Effects of the Invention] As described in 1-1 above, the present invention provides an electronic device driving circuit of an electronic device testing apparatus, in which at least two of a plurality of relays for switching connections between pins of an electronic device and a driver, etc. is mounted on a module independent from the circuit board of the electronic device drive circuit, the necessary wiring is done, and the module is mounted on the circuit board, so the stray capacitance of the circuit of the connection switching relay is reduced compared to the conventional method. Thus, it is possible to realize an electronic device drive circuit that reduces waveform distortion of the pin output signal of the electronic device.

[Brief explanation of drawings]

FIG. 1 is a schematic circuit diagram showing an embodiment of an electronic device driving circuit according to the present invention. 10... Driver, 12.14... Comparator,
16...Module, DV...Electronic device, R1
-Rn...Reed relay for connection switching.

Claims (1)

[Claims] (1) In an electronic device testing apparatus, in an electronic device drive circuit that includes a plurality of relays for switching connections between pins of an electronic device to be tested and a driver, etc., at least two of the plurality of relays are An electronic device drive circuit characterized in that it is mounted on a module independent from the circuit board of the device drive circuit, necessary wiring is made, and the module is mounted on the circuit board.