How to measure the quality of A3120 optocoupler?

Novices don't know how to measure the quality of the optocoupler, the master teaches you a trick, and you can learn it in a few minutes.

It is a device that uses light as the medium to transmit electrical signals, A3120 optocoupler is a special optocoupler that drives FETs or IGBTs, and the 5 pins are negative voltage inputs, usually using -5V voltage.

The function is: when the optocoupler pin has a current flowing through, the pin outputs a high level, drives the IGBT module to turn on, and when the pin light-emitting diode is cut off, the voltage of the pin is negative voltage through the 5-pin negative power supply, and the post-stage IGBT is quickly cut off, so as to ensure that the IGBT will not be damaged.

Uses: Light is used as the medium to transmit electrical signals, usually the light emitter (infrared light-emitting diode LED) and the light receiver (photosensitive semiconductor tube, photoresistor) are encapsulated in the same tube shell. When the input terminal is energized, the luminaire emits light, and after the light receiver receives the light, it generates photocurrent, which flows out from the output terminal, thus realizing the "electricity-optical-electric" conversion.

Optocoupler uses light as the medium to couple the input signal to the output optocoupler, because it has the advantages of small size, long life, no contact, strong anti-interference ability, isolation between output and input, one-way transmission of signals, etc., it has been widely used in digital circuits.

Features::

l 2A minimum peak current output.

l 15kV insulation withstand voltage.

l Maximum low-potential output (except negative bias) l 5mA supply current.

l Undervoltage lockout.

l 500ns maximum switching time l 15-30V wide voltage working environment, -40-150 degrees working temperature l Industrial temperature range: -40-100 degrees l Safety certification: UL, VDE0884 Application:

IGBT MOSFET driver.

AC motors. Brushless DC drive.

Inverter switching power supply.

Truth Table: Typical Circuit Connections:

It is HCPL-3120, which drives IGBT and MOSFET in isolation, and the driving current can reach 2A

For more details, you can see the datasheet

It is a device that uses light as a medium to transmit electrical signals, A3120 optocoupler.

It is specially designed to drive the spring hood FET.

Or a dedicated optocoupler for IGBTs, pin 5 is the negative voltage input, usually using -5V voltage.

The function is: when there is a current flowing through the optocoupler pin, the pin outputs a high level.

Drive the IGBT module to turn on when the foot LEDs.

At cut-off, the voltage of the pin is negative through the negative power supply of 5 pins, which provides a fast cut-off of the post-stage IGBT, so as to ensure that the IGBT will not be damaged.

According to the internal structure of the optocoupler, two multimeters can be used to measure its quality, that is, a mechanical watch is connected to the pin of the internal light-emitting tube, the black pen is connected to the anode of the internal light-emitting diode, and the red pen is connected to the cathode. When connected, the other two feet should be measured by the 10,000 meter to conduct energy, and when the mechanical watch is disconnected, it is cut off again.

This can only roughly measure the quality of the optocoupler, and it is best to use the substitution method to distinguish the good from the bad.

Hello, it is a pleasure to serve you and give you the following answer: you can use A331K instead of A331J. Causes of the problem:

The A331J is an old-fashioned optocoupler that may no longer be able to meet the needs of current applications and may fail. Solution: A331K can be used to replace A331J, because A331K is a new type of optocoupler, its performance is better than A331J, and it can better meet the current application requirements.

Steps: 1. First, check whether A331J exists in the circuit diagram, and if it exists, please remove it. 2. Then, install the A331K in its original position and fix it on the circuit board.

3. Finally, check whether the circuit connection is correct to ensure that the electric fiber is running normally. Related knowledge: A331K is a new type of optocoupler, which uses the latest technology, with high precision, high reliability, low cost and other advantages, can meet the needs of today's applications.