TPS22958: Intermittently fails to turn on

peter bradbury

Part Number: TPS22958

Hello TI forum.

The load switch will usually not work. But sometimes after trying a lot, it will start working. And then it might work for a little bit and then suddenly stop working. I have replaced the part twice now on two different boards. One board it is working 100% of the time (So far) the other board is still having trouble. I have three per board. One is switching 1.8v, one is switching 3.3v, and the other is switching 5v. They all have 5v bias.

CARRIER_PWR_ON is 1.8v high but even if I try 3.3V it makes no difference. I appreciate the help.

over 3 years ago

0 peter bradbury over 3 years ago

Prodigy 10 points

Just to add: I have replaced CT (C218 in the schematic above) to 1000 pF to reduce rise time. Makes no difference in regard to intermittent operation. It does speed up rise time in other working switches.

0 peter bradbury over 3 years ago

Prodigy 10 points

Also would like to add:

The working switch (VIN is 1.8V), the voltage on CT pin is 9.17V

The failing switches the voltage on CT pin is ~0.6V -0.75V

0 Kalin Burnside over 3 years ago in reply to peter bradbury

TI__Genius 13300 points

Hello Peter,

In order to better understand the event and to solve this quicker could you provide scope shots of Vin, Von, Vout, and Iout during the event?

Regards,

Kalin Burnside

0 Kalin Burnside over 3 years ago in reply to Kalin Burnside

TI__Genius 13300 points

Hello Peter,

Since I haven't heard from you in 10 days I am going to go ahead and close this thread.

Regards,

Kalin Burnside

Power management

Power management forum

TPS22958: Intermittently fails to turn on