DRV8701: DRV8701 Charge pump capacity

Hello Pritesh,

I will be happy to assist you. Most of our devices have a charge pump capacity of 12mA at the higher voltages. However to power the FETS you should be able to adjust the current applied. The peak drive current of the gate drivers is adjustable through the IDRIVE pin. Peak source currents may be set to 6, 12.5, 25, 100, or 150 mA. The peak sink current is approximately 2× the peak source current. Adjusting the peak current changes the output slew rate, which also depends on the FET input capacitance and gate charge. More information about this including graphs of its behavior can be found on section 7.3.5 of the datasheet on page 18.

Please let me know if you have other questions:

https://www.ti.com/lit/ds/symlink/drv8701.pdf?ts=1628523664132&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FDRV8701

If this is not sufficient I would also take at look at DRV8705 as the gate drivers support up to 62-mA source and 62-mA sink peak gate drive current capability.

https://www.ti.com/lit/ds/symlink/drv8705-q1.pdf?ts=1628523264007&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FDRV8705-Q1

Best,

Pedro Arango Ramirez. 

Pritesh,

The DRV8705-Q1 has up to 15mA, but that is the highest in the portfolio.  Is it possible to switch as lower frequency like 20kHz?  Still out of the audio band and would help your situation.

We do not have any suggested modifications for increasing the charge pump capacity as this would affect reliability as the internal metal connections are sized for the specification in the datasheet.  

Regards,

Ryan

Hello Pritesh,

As Ryan said in the previous post the DRV8705-Q1 is the highest rated device with up to 15mA, none of our devices can go higher than that for the charge pump. My suggestions would be to lower the frequency or choose FETs with lower gate charge. 

Best,

Pedro Arango Ramirez