HI :
I have met a problem about TPS54326 and TPS54626. In my system ,I need some voltage ,including 1.0V ,3.3V and 5V . There are power sequence requirement of these voltages , First 1.0V ,then 3.3V and 5V .
1.0V is privided by TPS54326 , 3.3V is provided by TPS54626 ,5V is provided by TPS54326. To meet the power seqence. I pull up the Power GOOD signal of 1.0v's TPS54326 and it is connected with the 5v's TPS54326 and 3.3'v TPS54626 Enable control signal. But I find that 3.3V can work correctly while 5V cannot work.
we also do test .first we cut off all the 3.3V and 5v load ,the problem still exits. Sometimes we use touch the 5V's TPS54326 Enable control signal using multimeter , it can work sometimes. But the board power down and power up again ,5V has no output. it looks very strange.
We have checked the solding condition and confirm that there is no problem about the solding. We also measure the Software start and EN control signal , it looks good . The input voltage is stabe,12V .
All the TPS54326 and TPS54626 component parameters have been checked and it is designed by the webbench tool.
I have a questtion , Can I connect the PG signal of TPS54326 with the other TPS54326 and 54626 Enable signal ?
