So apparently during power up the MCU can't be depended on to react quickly enough to take control of the MOS gates and they may misbehave. So it's recommended to put some pull-down resistors (or pull-up if PMOS) on the NMOS gates to keep the in a known state in the absence of everything else.
The possible problem is that the NMOS are being powered from a boostrap circuit and the presence of a pull-down resistor at any value makes the charge in the boostrap cap not last nearly as long as it could since it is constantly leaking current.
Would it do the job to pull the gate driver inputs low instead? Obviously it would if the gate driver had power to it...but what if it doesn't power up in time? It would probably power up a lot faster than the MCU, or it might not (it's being powered from a boost converter that also needs time to set up). Either way, it still might not power on fast enough to propogate the control signal to the MOS gate in time since when the battery is connected, the voltage appears across the MOSFETs right away whereas the driver and it's boost converter need time to power up. Whereas directly pulling the gate low would have the gate always be in a known state even if no power was applied.
Or should I just make it simple and use a ridiculously high pull-down resistor directly on the gate (like 1M or 10M).
The possible problem is that the NMOS are being powered from a boostrap circuit and the presence of a pull-down resistor at any value makes the charge in the boostrap cap not last nearly as long as it could since it is constantly leaking current.
Would it do the job to pull the gate driver inputs low instead? Obviously it would if the gate driver had power to it...but what if it doesn't power up in time? It would probably power up a lot faster than the MCU, or it might not (it's being powered from a boost converter that also needs time to set up). Either way, it still might not power on fast enough to propogate the control signal to the MOS gate in time since when the battery is connected, the voltage appears across the MOSFETs right away whereas the driver and it's boost converter need time to power up. Whereas directly pulling the gate low would have the gate always be in a known state even if no power was applied.
Or should I just make it simple and use a ridiculously high pull-down resistor directly on the gate (like 1M or 10M).
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