Other Parts Discussed in Thread: TPS51200, TPS53355, TPS548A20
Hi
My board is using TPS53515 as power supply, buffer SN74LVC1G125DCKT.
For now, I have 4 boards, working around 8 mouths (all day every day). The working temperature on PCB is around 70°C.
Power good pin on 4 TPS53515 and 2 TPS51200 are connected in parallel.
A pull-up resistor and buffer is connected to net and the warning signal conduct via the buffer SN74LVC1G125DCKT.
Phenomenon：
1. On first board, leakage current is around 600uA. We changed SN74LVC1G125DCKT, fault removed.
2. On second board, we removed buffer. The output is 200mV, pull-up resistor is 40.2K, leakage current is around 70uA. However, all output voltage on each power supply as good.
3. The third board, total leakage voltage is 20uA, we switched a small resistor then continue to work.
Summary:
After working in high temperature for long period, the leakage current on pgood pin on both TPS53515RVET，TPS51200DRCT will increased to a unaccepted level. But the output on each power supply are working well.
Is this a common Phenomenon for TPS53515RVET，TPS51200DRCT？Any suggestion for this case to avoid leakage current increase?
