Dear team
The product of TPS563231DRLR (VR4) has been burnt out recently.
The burned-out place is the Pin1 (Vout) and Pin2(SW), please refer to the figure below. Could you help to review the schematic and layout?
RT5010W-D187-RoHS-REV3.5.-0807-t.ziprt5010w-d187_power.pdf
Under what conditions, is there a chance to cause this phenomenon!!
If you need more information from the issue, please kindly suggest me.
Many thanks
Denny
Hi Ruby
The software tool is PADS.
1. would you please do me a favor to capture the waveform of Vin, SW, iL and Vout when it burnt out? And Vin, Vboot, iL and Vout in the same wavform.
=> The ic can't work,
Vin to ground impedance: 17 ohm
Vout: CP283 impedance to ground: 6 ohm
Top layer
Bottom layer
For layout, Could you help to provide some suggestions?
2.How many pcs out of total had this issue?
fail 20pcs / total 400k pcs
3.Would you please do me a favor to take a photo of the broken IC?
Many thanks
Denny
Hi Ruby
Could you have any suggestions on schematic and layout?
I have capture the waveform of VDS of high side and low side mos.
VDS of high side
VDS of low side
Many thanks
Denny
Hi Denny
Here are my comments：
For the schematic,
1. The input cap's voltage tolerance is only 16V but with 12V input, the derating will be large. Also, the output cap's voltage tolerance is a little bit low for 3.3V Vout. So I would recommend to use caps with higher voltage tolerance for both input and output, or add one 22uF cap for the input and another 22uF for the output.
2. I would recommend to add RC snubber to the SW pin to reduce the ring.
For the layout:
Just one tiny thing, I would recommend to move the inductor higher, so that the area of the copper for SW can be reduced a little because it is noisy. And then, enlarge the copper for Vin. Others look good.
BR
Ruby
