ISO1430: ISO1430 Driver is getting damaged

hilal a

Part Number: ISO1430

Tool/software:

Hello ,

We are using ISO1430BDWR with isolated power supply, during our testing we found that output resistance across the RS485 become 2 ohm. The driver is little bit getting heated up , Any suggestion for this issue

Regards

Aziz

7 days ago

0 Andrew J 6 days ago

TI__Mastermind 28745 points

Hello Aziz,

Thank you for reaching out. 2-ohms is very close to a short which could cause device heating when power is applied.

hilal a said:
during our testing we found that output resistance across the RS485 become 2 ohm.

Can you please provide additional details on how you are measuring 2-ohms? Which pins are our measuring and where on the schematic?

Best,
Andrew

0 hilal a 5 days ago in reply to Andrew J

Prodigy 170 points

Measured between the Driver output pin A & B to Ground . I have question since this is a isolated transceiver, if the isolated grounds got shorted is there any chance the chip get damaged

Regards

Aziz

0 Andrew J 4 days ago in reply to hilal a

TI__Mastermind 28745 points

Hi Aziz,

The 2-ohm resistance is unusual. For next steps see below:

Confirm that the device is non-functional (no outut switching).
Un-power the device and measure pin resistance. Also measure the VCC to GND resistance.
Replace the device with a new ISO1430 and see if the board begins to work. Remove the new unit if the PCB works and return the suspected damaged unit. This will confirm if the unit is damaged.

To answer "if the isolated grounds got shorted is there any chance the chip get damaged":

No, connecting GND1 and GND2 would not damage the device, and it will continue to function. However, isolation barrier would be bypassed side 1 and side 2 pins would not be isolated.

Best:
Andrew

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ISO1430: ISO1430 Driver is getting damaged