Hi Ti member,
I have one question about the output current report problem (not accurate) with the TPS40400.
MY evaluated board is TPS40400EVM-351, therefore the current sense element is the inductor's DCR.
The inductor value is 0.47uH, and its DCR=0.85mohm.
According the application condition and inductor's parameters, I filled it in “Fusion Digital Power Designer” program.
However, the output current report value is not accuracy.
Please refer the test result as below table.
Condition: Vin=12V, Vout=5V, Iout Cal Gain: 0.85mohm | ||||||||||
Real Iout (A) | 2 | 4 | 6 | 8 | 10 | 12 | 14 | 16 | 18 | 20 |
Iout_read (A) | 5.38 | 7.69 | 9.81 | 11.81 | 14 | 16 | 18.38 | 20.56 | 22.81 | 25.25 |
**Note: (1). “Real Iout” is the real output current (sink from E-loader)
(2). “Iout_read” is the value read from Fusion.
Would you help to give me some suggestions that would get more accurate output current through PMbus?
Best Regards,
Lance