TPS565201: High ripple on inductor current

Kazuto Tatsumi

Part Number: TPS565201
Other Parts Discussed in Thread: TPS56528Hi,

According to the WEBENCH result, the inductor current ripple is about 34% at Vin=12V, Vout=5V, Iout=4A. Is it no problem or too high? I have also tried to simulate with TPS56528, but the ripple is 23%, it seems better.
TPS563201
TPS56528

Best Regards,
Kazuto

over 3 years ago

0 Yuchang Zhang over 3 years ago

TI__Mastermind 18510 points

Kazuto-San, As we know, the ripple current is impacted by Fsw and L value, and generally 20%~40% Ioutmax, are all acceptable, so this two results should both be ok.

Yuchang

0 Kazuto Tatsumi over 3 years ago in reply to Yuchang Zhang

TI__Intellectual 2820 points

Hi Yuchang, thanks for your comment.

Around 4A, it seems no problem as you said. However if the load current goes down to 2A, it's still in CCM, and the inductor current ripple ratio is about 80%. Is it still no problem?

I put the WEBENCH below.
https://webench.ti.com/appinfo/webench/scripts/SDP.cgi?ID=2EBE5B0E199C4B4C
Regards,
Kazuto

0 Yuchang Zhang over 3 years ago in reply to Kazuto Tatsumi

TI__Mastermind 18510 points

Kazuto-san,

We recommend to set the ripple current value based on the max Iout spec, such as if the part is 5A ability, you need design Ip-p based on 5A rather than 2A or others. if not, if you use only 100mA, the inductor value will be much bigger, not make sense for 5A part...

Yuchang

0 Kazuto Tatsumi over 3 years ago in reply to Yuchang Zhang

TI__Intellectual 2820 points

Hi Yuchang,

The load current can go up to 5A, but it's not maintained, sometimes go down to 2A in the light load condition. In this case, should I recommend the customer to use bigger inductance to maintain the ripple ratio within 40% at 2A load?

Regards,
Kazuto

0 Yuchang Zhang over 3 years ago in reply to Kazuto Tatsumi

TI__Mastermind 18510 points

Kazuto,

Don't need to do this, keeps 5A design.

Yuchang

Power management

Power management forum

TPS565201: High ripple on inductor current