Hi all,
I used UCD9244+UCD74120 to generate 1.0V to supply the Keystone II SOC's core power.
Now we have not mounted the SOC yet. We just debug the UCD9244+UCD74120.
And I met a problem that is the dramatically changing in voltage which UCD9224 detects.
My design is the same as page 40 in the attached pdf file 6403.K2H_K2EVM-HK_SCH_A104_Rev4_0.pdf EXCEPT I removed the MCP9700AT so there is no temperature related voltage into the TEMP/AuxADC pin of UCD9244.
The TEMP/AuxADC pin of UCD9244 is just connected with one 1000pF capacitor to GND.
And in the Fusion Digital Power software, I got the voltage that the UCD9244 detects, namely is what the UCD74120 generates changes dramatically.
I must raise the Overvoltage value above 1.5V, otherwise this channel will be closed immediately.
Does the no connection to temperature related voltage to TEMP/AuxADC of UCD9244 causes this problem?
Or something else?
Regards,
Feng