JPS6145785B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a wiring inspection device that automatically and quickly inspects the quality of wiring in electronic devices and the like.

Conventionally, relays, SCRs, and the like have often been used as elements for switching each wiring terminal in wiring inspection equipment. However, in recent years, the amount of wiring in electronic devices has become extremely large, often reaching tens of thousands of wires, and relays, SCRs, etc. are not suitable for large-capacity wiring inspection equipment in terms of operating speed, power consumption, and space they occupy. It is not suitable as a switching element. Therefore, field effect transistor (hereinafter abbreviated as FET)
Devices have been developed that use the switching element as a switching element, but the ON resistance value is several hundred ohms, which is large compared to relays, etc., and the variation is also large, so the reliability is not sufficient.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a wiring inspection device that eliminates the above-mentioned drawbacks and can perform wiring inspection automatically and at high speed.

According to the present invention, a first FET group connects each wiring terminal to the first common line, a second FET group connects each of the wiring terminals to the second common line, and a reference wiring terminal connects the first FET group to the first common line. a first relay that connects to a common line, a second relay that connects the reference wiring terminal to the second common line, and any FET of the first and second FET groups and the first and second relays. a selection section having a means for selecting and opening/closing; a power source that supplies voltage to the first common line; a detection section that senses the voltage of the second common line and calculates and outputs a resistance value; It consists of a storage section that stores the ON resistance value of each FET of the second FET group, and a control section that controls the selection section, inspects the wiring state based on the output of the detection section and the information of the storage section, and outputs it to the outside. An automatic wiring inspection device is obtained.

The figure is a block diagram showing one embodiment of the present invention, in which the device to be inspected 1 has wiring terminals P ₁ , P ₂ , P ₃ , and a reference wiring terminal P ₄ , and P 1 and P 3 are wiring terminals P 1 , P ₂ , P ₃ , and a reference wiring terminal P 4 . are connected to form circuit 2. FETs S ₁₁ , S ₁₂ , and S ₁₃ form a first FET group, and FETs S ₂₁ , S ₂₂ , and S ₂₃ form a second FET group. The drain terminals of the FETs in the first FET group are all connected to the power supply 6 through the first common line 4, and the other terminals are connected to the respective wiring terminals. Further, the source terminals of the FETs of the second FET group are all connected to the detection unit 7 for detecting the voltage level through the second common line 5, and the other terminals are connected to the respective wiring terminals. The FETs of the 1st FET group are
When turned on, the corresponding wiring terminal is connected to the power supply,
When the FETs of the second FET group operate, the corresponding wiring terminals are connected to the detection section 7. Each FET can be independently opened and closed by a signal from the selection section 8. relay
One terminal of _R1 is connected to the power supply 6 through the first common line 4.
The other terminal is connected to the reference wiring terminal _P4 . Furthermore, one terminal of the relay _R2 is connected to the detection section 7 for detecting the voltage level through the second common line 5, and the other terminal is connected to the reference wiring terminal _P4 . When relay R ₁ closes, reference wiring terminal P ₄ is connected to the power supply, and when relay R ₂ closes, reference terminal P ₄ is connected to detection section 7 . Relays R ₁ and R ₂ can be opened and closed independently by signals from selection section 8. The pre-memory section 10 receives each output from the detection section 7.
The ON resistance value of each FET is stored and sent to the control unit 9 as necessary. Control unit 9
controls all FETs and relays through the selection section 8, and at the same time receives the output from the detection section 7 and the ON resistance value of the FET from the storage section 10, judges whether the wiring is good or bad, and outputs the result.

Next, the operation of the present invention will be explained. Control unit 9
It is assumed that the wiring information of the device to be inspected is input and stored in advance. First, the ON resistance value of each FET is measured and stored in the storage unit 10. of each FET
The method for measuring ON resistance value will be explained using FET _S11 as an example. Connect unit 3, in which wiring terminals P ₁ , P ₂ , P ₃ , and reference wiring terminal P ₄ are all short-circuited, to the wiring inspection device, turn on FET S ₁₁ and relay R ₂ , and check other FETs,
Turn off all relays. By doing so, the power supply voltage is connected to the detection section through FET S ₁₁ , terminals P ₁ , P ₂ , P ₃ and relay R ₂ . Relay R ₂
Since the ON resistance and the wiring resistance of the wiring terminals P ₁ , P ₂ , and P ₃ are approximately 0, the ON resistance value of the FET S ₁₁ can be calculated from the voltage and current input to the detection unit 7. By sending the calculated value to the storage unit 10
Registration of the ON resistance value of FET S ₁₁ is completed. Remaining
The ON resistance value of the FET is also measured using the same procedure and registered in the storage unit 10. Next, the device to be inspected 1 is connected to the wiring inspection device, and all FETs and relays are turned OFF using a signal from the control section 9. First, the wiring circuit 2 is tested for continuity. For this we first need to use the FET
Turn on _S11 and apply power supply voltage to wiring terminal _P1 . next
Turn on FET S ₂₃ and connect wiring terminal P ₃ and detection section 7. If there is a wire between the wire terminals P ₁ and P ₃ , the power supply voltage is applied to the detection section 7 and from the detection section 7 to the control section 9 .
The resistance value between the wiring terminals P ₁ and P ₃ is sent to the control unit 9, and the resistance value is sent from the storage unit 10 based on this resistance value.
The sum of the ON resistance values of FETs S ₁₁ and S ₂₃ is subtracted, and as a result, the control unit 9 determines that the wiring terminals P ₁ and P ₃ are in a conductive state. If there is no wire between the wire terminals P ₁ and P ₃ , no voltage will be applied to the detection section 7 and an extremely high resistance value will be sent from the detection section 7 to the control section 9 .
In this case, it is determined that there is an insulating state between the wiring terminals P ₁ and P ₃ and it is stored as a defect. Next, an insulation test is performed between the wiring circuit 2 and all other wiring terminals. For this, first
Turn on FETs S ₁₁ and S ₁₃ and connect wiring terminals P ₁ and P ₃ to the power supply. Next, turn on FET S ₂₂ and connect wiring terminal P ₂ to detection section 7. If the wiring circuit 2 is insulated from the wiring terminal _P2 , no voltage is applied to the detection section 7. If there is continuity between the wiring circuit 2 and the wiring terminal _P2 , a voltage is applied to the detection unit 7, and the control unit 9 detects the voltage between the wiring circuit 2 and other terminals using the same means as in the continuity test. It is determined that there is continuity and it is stored as a defect. The above-described inspection is performed on all the wiring circuits of the device to be inspected 1, and the control section 9 outputs the defective locations stored in the process, and the inspection is completed.

As described above, according to the present invention, FETs with small drive current are used as switching elements, and each FET is turned on.
Since the resistance value is corrected, it is possible to realize a small device with low power consumption and high accuracy in determining whether the wiring is good or bad. Furthermore, continuity and insulation between a large number of wiring terminals can be tested automatically and at high speed. For example, it is possible to speed up inspections after assembly in factories, etc., which can reduce the cost of products. The effect is extremely large.

[Brief explanation of the drawing]

The figure is a block diagram showing an embodiment of the wiring inspection device according to the present invention, in which 1 is a device to be inspected, 2 is a wiring circuit, 3 is a short circuit unit, 4 is a first common line, 5 is a second common line, 6 is a power supply, 7 is a detection section, 8 is a selection section,
9 is a control unit, 10 is a storage unit, S ₁₁ , S ₁₂ and S ₁₃ are
The first FET group, S ₂₁ , S ₂₂ , and S ₂₃ are the second FET group, and R ₁ and R ₂ are relays.

Claims (1)

[Claims] 1 A first FET group that connects each wiring terminal to the first common line, a second FET group that connects each wiring terminal to a second common line, and a reference wiring terminal that connects to the first common line. a first relay that connects the reference wiring terminal to the second common line, and an arbitrary FET of the first and second FET groups.
a selection unit having means for selecting and opening/closing the first and second relays, a power source for supplying voltage to the first common line, and sensing the voltage of the second common line to calculate and output a resistance value. a detection unit for controlling the ON resistance value of each FET of the first and second FET groups, and a storage unit for controlling the selection unit and inspecting the wiring state based on the output of the detection unit and the information in the storage unit. Automatic wiring inspection device consisting of a control unit that outputs to the outside.