The temperature control module made of max1978 chip broke down again

秋天的琴湖

The temperature control module made of max1978 chip broke down again [Copy link]

 

The board made of max1978 chip has a large current at the beginning of power-on, and then it will become smaller. When powered on, the large current often cannot be reduced. After inspection, it was found that there is a structure similar to an H bridge inside the chip, and the grounded nmos tube is always broken down. I don't know if it is a problem with pid control or the H bridge peripheral circuit. Thank you for your help

qwqwqw2088

Burning MOS tubes may be caused by large current. The reason for the large current should be carefully checked to see if the MOS tube power is insufficient or the peripheral circuit of the bridge is unreasonable. PID control generally sets parameters. If the parameter settings are unreasonable, many accidents will occur.

电子微创意

It should be related to the control loop parameter setting, for infrared?

秋天的琴湖

almost

秋天的琴湖

It is a problem of static electricity and power supply. It must be grounded strictly.

fengchao989

I also encountered this problem. Some of them broke down after running for a period of time, and some broke down as soon as they were powered on. What improvements did the OP make to solve it?

guitianxia

The MAX1978 /MAX1979 are the smallest, safest, and most accurate fully monolithic temperature controllers for Peltier thermoelectric cooler (TEC) modules. On-chip FETs and thermal control loop circuitry minimize external...

秋天的琴湖

Since power-on overshoot and electrostatic interference can damage devices, we should add protection.

xiaxingxing

I have used similar TEC control chips. I used ADN8834, and the chip burned for a while. I remember that the NMOS to ground burned out. Later I found out that the cause was the pulse voltage caused by hot plugging.

YangSQ

Just add a 6V~7.5V TVS tube to the output end

秋天的琴湖

YangSQ posted on 2020-12-2 17:33 Just add a 6V~7.5V TVS tube to the output end

Has the host practiced it?

17805569

Can you please send me the AD library of MAX1978? I am also working on it.

qwqwqw2088

17805569 Published on 2020-12-15 22:42 Can you please send me the AD library of MAX1978? I am also working on it.

TQFN;48 package

You can find a package like this and then refer to the manual to modify the size. The modification should not be too big.

秋天的琴湖

TVS tube is a good thing.

秋天的琴湖

xiaxingxing posted on 2020-12-1 17:30 I have used similar TEC control chips. I used ADN8834, and the chip burned for a while. I remember that the NMOS to ground was also burned. Later I found out that the reason was...

TVS tube can solve this pulse voltage

秋天的琴湖

fengchao989 posted on 2018-12-27 08:10 I also encountered this problem. Some of them were broken down after running for a period of time, and some were broken down as soon as they were powered on. What improvements did the OP make to solve it?

Add TVS tube

秋天的琴湖

xiaxingxing posted on 2020-12-1 17:30 I have used similar TEC control chips. I used ADN8834, and the chip burned for a while. I remember that the NMOS to ground was also burned. Later I found out that the reason was...

How did you solve it?

秋天的琴湖

YangSQ published on 2020-12-2 17:33 Just add a 6V~7.5V TVS tube to the output end

The output terminal you are talking about is between VCC and GND, right?

秋天的琴湖

TVS tube, SMBJ5.0A

秋天的琴湖

Overcurrent and overvoltage protection chip, has anyone tried it?