This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

MAX3232: MAX3232 failed - without heating issue

Part Number: MAX3232

We are seeing the MAX3232C failures which is used for communication in our project. We saw 2 failures out of 10 boards. Remaining 8 boards will communicate properly.  Can you help us to understand failure modes and possible cause of failure of this IC. Our Part of Design is attached for your reference.

 

Failed IC condition is as of below:

VCC = + 5V

Pin No.

Pin Name

Capacitor Value ( Ceramic Capacitor)

Measured Voltage

1

C1+

0.1µF (Pin1 to Pin3)

+0.3V

2

V+

0.1µF (Pin2 to GND)

+0.03V

3

C1-

 

+0.05V

4

C2+

0.1µF (Pin4 to Pin5)

+0.05V

5

C2-

 

+0.04V

6

V-

0.1µF (Pin6 to GND)

+0.3V

7

Dout2

 

+0.3V

8

RIN2

 

+0.3V

9

Rout2

 

+0.73V

10

DIN2

 

+5.02V

11

DIN1

 

+5.02V

12

ROUT1

 

+0.7V

13

RIN1

 

+0.3V

14

DOUT1

 

+0.3V

15

GND

 

0V

16

VCC

0.1µF (VCC to GND)

+5.03V

 

Note : IC not heating up and not taking abnormal current.

 

 

 

  • Girish,

    Thanks for providing the measurement data. But somehow I didn't see your design file. Also it would be helpful for debug if you could take some waveforms of V+/V- pins of the failed parts.

    From my experience with MAX3232, in many times the likely root cause is electrical overstress of the charge pump pins (V+/V-), whose abs max is 7V/-7V. The first thing you can check is if the voltage rating of the external capacitors is at least 10V. Then you can look for if there are any abnormal overshoot voltage on these pins during operation. To help understand the failure, you can also contact TI quality team through your vendor. They will do failure analysis on the failed parts.

    Regards,
    Hao