Hello Motor driver team,
My customer is asking about safe operation condition not to damage FETs in H-bridge output of DRV8838.
Some condition of Vin or load impedance makes undesired overshoot and undershoot on output waveform during H-bridge switching.
My customer wants to know how much overshoot or undershoot DRV8838 output FET can withstand without damage risk.
What is the maximum overshoot/undershoot voltage? My customer is asking about SOA(safety operation area) of FETs in H bridge. An example is attached.
Here's their test data with 6V input and various PH pin signal(frequency and duty) in customer application. Is it safe operation for DRV8838?
11.5 ohm |
6V |
30khz |
70khz |
100khz |
||||||
duty |
10% |
50% |
90% |
10% |
50% |
90% |
10% |
50% |
90% |
|
Overshoot |
Max |
7.16 |
7.08 |
7.16 |
8.04 |
7.16 |
7.24 |
8.6 |
8.76 |
7.08 |
Undershoot |
Min |
-0.6 |
-0.84 |
-0.92 |
-0.6 |
-0.84 |
-0.44 |
-0.52 |
-0.84 |
-0.84 |
Thank you.