Other Parts Discussed in Thread: TPS23881,
Tool/software:
Hi Sir,
I used the TPS23882RTQR + SRAM (TPS23881_2_SRAM_CODE_v15) to implement a 48-port 802.3at Type 2 PSE Ethernet switch and found a problem when we doing power cycle test.
The PSEs tested with Sifos’s Multi-Port Live PD Emulation and are set to Class 4 load (30W per port).
At every power cycle, we loaded the SRAM code into the PSE and check if the download was successful.
But there are random ports at random time have lower power supply from the TPS23882 (Found once abnormal in 6x times).
We dumped the contents of the abnormal port's (port 18 to 20) registers and did not find any fault events occurring.
However, the channel (2-4) request class result indicated that they were “Class 4+ - Type-1 Limited” and assigned class are 3.
You also could see the power allocation we are setting “2-pair 30W” for each channel.
Below are the initial commands sent to the TPS23882,
Write 0x1a 0xdf
Write 0x12 0xff
Write 0x29 0x33
Write 0x14 0xff
Write 0x15 0xf0
We do
Do you have any experience with this problem? Thanks~
