TPS3823: how to disable TPS3823 when burning program into MCU

Sirui Zhu

Intellectual 2090 points

Part Number: TPS3823
Other Parts Discussed in Thread: TPS3852, TPS3850

Hi team,

If we use TPS3823 to co-work with MCU, the MCU cannot send WDI signal to clear the timmer when burning program. Is there any suggestion to prevent TPS3823 reset MCU in this senario?

Sirui

over 3 years ago

0 Jesse Villanueva over 3 years ago

TI__Mastermind 18690 points

Hi Sirui,

Thank you for your question, I'll be happy to help. Do you know the status of the GPIO during programming?

One thing to note is that when the WDI is set to a high impedance state the watchdog is going to be disabled, so 1 work around opening the WDI line during programing.

Jesse

0 Sirui Zhu over 3 years ago in reply to Jesse Villanueva

TI__Intellectual 2090 points

Hi Jesse,

Thanks for replying. The GPIO will remain high or low during programming, depending on the MCU config, and cannot clear the watchdog timer.

Do you think a 0ohm resistor in series between MCU and WDI works in this case? Desoldering the resistor when programming. Or there are other praticular way to solve this issue?

Sirui

0 Sirui Zhu over 3 years ago in reply to Sirui Zhu

TI__Intellectual 2090 points

Or is there any other device you could recommend to solve the reset during programming issue?

0 Jesse Villanueva over 3 years ago in reply to Sirui Zhu

TI__Mastermind 18690 points

Hi Sirui,

A shorting plug would be my recommendation, but desoldering a 0ohm resistor would work too.

For another device recommendation, a device with a SET pin, such as TPS3850 and TPS3852, should do the trick.

The SET pin will allow you to enable and disable the WD at will.

Jesse

0 Sirui Zhu over 3 years ago in reply to Jesse Villanueva

TI__Intellectual 2090 points

Hi Jesse,

Thanks for the recommend. Customer need online upgrade firmware, so plug or 0ohm resistor don't work for them. I've recommend them to use TPS3850.

Sirui

Power management

Power management forum

TPS3823: how to disable TPS3823 when burning program into MCU