CN211402631U

CN211402631U - Device for testing open and short circuit of circuit by using chip pin characteristics

Info

Publication number: CN211402631U
Application number: CN201922116429.8U
Authority: CN
Inventors: 徐欢夏
Original assignee: Jiangsu Liankang Electronics Co ltd
Current assignee: Jiangsu Liankang Information Co.,Ltd.
Priority date: 2019-12-02
Filing date: 2019-12-02
Publication date: 2020-09-01
Anticipated expiration: 2029-12-02

Abstract

The utility model discloses a device for testing circuit open and short circuit by utilizing chip PIN characteristic, which comprises a testing device and an integrated circuit to be tested, wherein the testing device comprises a DC input module, a display module, a voltage stabilizing circuit, a microprocessor, an analog-digital converter and an analog multiplexer, the integrated circuit to be tested comprises a protection diode, the display module and the analog-digital converter are connected on the corresponding port of the microprocessor, the input end of the analog multiplexer is connected with the PIN PIN of the integrated circuit to be tested, the output end of the analog multiplexer is connected with the input end of the analog-digital converter, the problem that each PIN in the integrated circuit has the protection diode with VDD and GND is solved, and the protection diodes all exist in a serial mode, when one of the light emitting diodes in the string is damaged, a short circuit occurs, which causes high current and high voltage to be accumulated on the integrated circuit, and the whole string is burned out, thereby requiring the test of the integrated circuit.

Description

Device for testing open and short circuit of circuit by using chip pin characteristics

Technical Field

The utility model belongs to the technical field of the circuit test, especially, relate to an utilize device of chip pin characteristic test circuit open short circuit.

Background

An IC, i.e. an integrated circuit, is a miniature electronic device or component, and is made up through such technological steps as interconnection of the elements and wires of transistor, resistor, capacitor and inductor, etc. and through multilayer or tunnel wiring to form a complete electronic circuit, and packaging in a tube.

Each pin, VDD and GND of the integrated circuit has a protection diode, and the protection diodes are all in the form of a string, and when one of the leds in the string is damaged, a short circuit occurs, resulting in high current and high voltage being accumulated on the integrated circuit, which may cause the entire string to burn out, thereby requiring testing of the integrated circuit.

SUMMERY OF THE UTILITY MODEL

In order to overcome every pin and VDD and GND all have the protection diode in integrated circuit, and the protection diode all exists with the tandem mode, has one of them emitting diode damage to take place the short circuit when the tandem, causes high current, high voltage gathering on integrated circuit, can cause the burnout of whole tandem, consequently need test integrated circuit, the utility model provides an utilize device of chip pin characteristic test circuit to open the short circuit adopts following technical scheme:

the utility model provides an utilize device of chip PIN characteristic test circuit short circuit, includes testing arrangement and integrated circuit that awaits measuring, and testing arrangement includes DC input module, display module, voltage stabilizing circuit, microprocessor, analog-to-digital converter and analog multiplexer, and the integrated circuit that awaits measuring includes the protection diode, and display module and analog-to-digital converter connect on microprocessor's corresponding port, and analog multiplexer input and the integrated circuit's that awaits measuring PIN foot is connected, and analog multiplexer output is connected with analog-to-digital converter's input.

Furthermore, the voltage stabilizing circuit is electrically connected with the integrated circuit to be tested, and the input end of the voltage stabilizing circuit is connected with a computer through a USB interface.

Further, the microprocessor is an AT89C52 singlechip.

Further, the display module is an LED display.

Has the advantages that: the utility model discloses an adopt DC input module, display module, voltage stabilizing circuit, microprocessor, the testing arrangement that analog-to-digital converter and analog multiplexer combined together, carry out the circuit test to the integrated circuit that awaits measuring, simple structure, efficiency of software testing is high, can pass through the study of microprocessor to the integrated circuit parameter of different models simultaneously, can realize that the integrated circuit of multiple model tests, and the utility model discloses can carry out the integrated circuit test alone, whether the switch-on welding that is connected with integrated circuit on also can testing PCBA board is opened, the short circuit, has had this kind of test method, PCBA is after the paster upper part, just can go out the welding effect with the very swift test of this kind of method, and need not assemble into the real machine and test to improve efficiency of software testing.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a schematic diagram of the PIN to VDD test of the present invention;

fig. 3 is a schematic diagram of the VSS to PIN test of the present invention.

In the figure: 1-testing device, 2-integrated circuit to be tested;

101-DC input module, 102-display module, 103-voltage stabilizing circuit, 104-microprocessor, 105-analog-to-digital converter, 106-analog multiplexer, 107-USB interface, 108-computer, 201-protection diode.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

Please refer to fig. 1, which illustrates an apparatus for testing open/short circuit of a circuit by using chip PIN characteristics, comprising a testing apparatus 1 and an integrated circuit 2 to be tested, wherein the testing apparatus 1 comprises a DC input module 101, a display module 102, a voltage stabilizing circuit 103, a microprocessor 104, an analog-to-digital converter 105 and an analog multiplexer 106, the integrated circuit 2 to be tested comprises a protection diode 201, the display module 102 and the analog-to-digital converter 105 are connected to corresponding ports of the microprocessor 1, an input end of the analog multiplexer 106 is connected to a PIN of the integrated circuit 2 to be tested, and an output end of the analog multiplexer 106 is connected to an input end of the analog-to-.

The voltage stabilizing circuit 103 is electrically connected with the integrated circuit 2 to be tested, the input end of the voltage stabilizing circuit 103 is connected with the computer 108 through the USB interface 107, the microprocessor 104 is an AT89C52 single chip microcomputer, and the display module 102 is an LED display.

The working principle is as follows: because the PIN of the integrated circuit 2 outputs an analog signal, the microprocessor 104 cannot recognize the analog signal, and therefore the analog signal is converted into a digital signal by the analog-to-digital converter 105, so that the microprocessor 104 can read the analog voltage, and the analog multiplexer 106 is selected to select which path of voltage to measure, and the selection can be controlled by the microprocessor 104, so that the use of one analog-to-digital converter 105 is realized, the resource cost is saved, and the structure is simplified.

Meanwhile, the voltage drop inside each integrated circuit 2 is different, and in order to enable the test device 1 to be generalized, before testing, the test device 1 learns a normal integrated circuit 2, learns the parameters of each pin, and adds four display modes of "IC open circuit", "IC short circuit", "adjacent pin short circuit" and "IC normal" in the display module 102.

The PIN foot that sends a signal for integrated circuit 2 by testing arrangement 1, because integrated circuit 2's PIN foot is inside to have protection diode 201, protection diode 201 itself has the pressure drop to can test out the correct pressure drop of this PIN foot, and whether reach this PIN foot and open a way or the short circuit, the utility model discloses efficiency of software testing is high, can carry out integrated circuit 2's test alone, and whether the switch-on welding that is connected with integrated circuit 2 on also can testing PCBA board is opened, the short circuit, has had this kind of test method, and PCBA is after the paster upper part, just can be with the test that this kind of method is very swift out the welding effect, and need not assemble into the real machine and test, thereby improves efficiency of software testing.

Signal testing principle:

IC open circuit test:

as shown in fig. 2, VDD of the integrated circuit 2 is set to 0V, the microprocessor 104 of the testing apparatus 1 sends high level data to the PIN of the integrated circuit 1 to be tested, the microprocessor 104 reads an output signal of the PIN of the integrated circuit 1, if the measured level is not changed, the diode between VDD and the PIN is open, the display module 102 displays "IC open", if the measured level is equal to the parameter learned by the microprocessor 104, the circuit is normal, and the display module 102 displays "IC normal".

As shown in fig. 3, VSS of the integrated circuit 2 is set to a high level, the microprocessor 104 of the testing apparatus 1 sends low level data to the PIN of the integrated circuit 2 to be tested, the microprocessor 104 reads the PIN output signal of the integrated circuit 1, if the level is not changed, the VSS is open to the PIN, the display module 102 displays "IC open", and if the measured level is equal to the parameter learned by the microprocessor, the circuit is normal, and the display module displays "IC normal".

IC short circuit test:

as shown in fig. 2, VDD of the integrated circuit 2 is set to 0V, the microprocessor 104 of the testing apparatus 1 sends high level data to the PIN of the integrated circuit 2 to be tested, the microprocessor 104 reads the PIN output signal voltage drop of the integrated circuit 2, if the voltage drop of the internal protection diode of the integrated circuit 2 is normal, the display module 102 displays "IC normal", if the voltage drop is lower than the voltage drop of the internal protection diode of the integrated circuit 2, the display module 102 displays "IC short".

As shown in fig. 3, VSS of the integrated circuit 2 is set to a high level, the microprocessor 104 of the testing apparatus 1 sends low level data to the PIN of the integrated circuit 2 to be tested, the microprocessor 104 reads the PIN output signal voltage drop of the integrated circuit 2, if the voltage drop of the diode inside the integrated circuit 2 is normal, the display module 102 displays "IC is normal", and if the voltage drop is lower than the voltage drop of the diode inside the integrated circuit 2, the display module 104 displays "IC is short-circuited" with VSS.

Short circuit test of IC adjacent PIN PINs:

the VDD of the integrated circuit 2 is set to be 0V, the microprocessor 104 of the testing device 1 sends low level data to a first PIN PIN of the integrated circuit 2 to be tested, the microprocessor 104 of the testing device 1 sends high level data to a second PIN PIN of the integrated circuit 2 to be tested, the microprocessor 104 reads the output signal voltage drop of the second PIN PIN of the integrated circuit 2, if the low level data exists, the adjacent PIN PINs of the integrated circuit 2 are in short circuit, the display module 102 displays 'adjacent PIN short circuit', if the high level data exists, the display module 102 displays 'IC normal'.

It is obvious to a person skilled in the art that the invention is not restricted to details of the above-described exemplary embodiments, but that it can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.

Claims

1. The utility model provides an utilize device of chip pin characteristic test circuit open short circuit which characterized in that: the test device comprises a DC input module, a display module, a voltage stabilizing circuit, a microprocessor, an analog-to-digital converter and an analog multiplexer, wherein the integrated circuit to be tested comprises a protection diode, the display module and the analog-to-digital converter are connected to corresponding ports of the microprocessor, the input end of the analog multiplexer is connected with a PIN PIN of the integrated circuit to be tested, and the output end of the analog multiplexer is connected with the input end of the analog-to-digital converter.

2. The apparatus for testing open and short circuit of circuit by using pin characteristics of chip as claimed in claim 1, wherein: the voltage stabilizing circuit is electrically connected with the integrated circuit to be tested, and the input end of the voltage stabilizing circuit is connected with a computer through a USB interface.

3. The apparatus for testing open and short circuit of circuit by using pin characteristics of chip as claimed in claim 1, wherein: the microprocessor is an AT89C52 singlechip.

4. The apparatus for testing open and short circuit of circuit by using pin characteristics of chip as claimed in claim 1, wherein: the display module is an LED display.