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How can I design a MOSFET H-bridge motor driver controlling only 1 PWM for a motor?

I also wish to use BTS50055 Highside High Current Power Switch for current sensing in the motor driver. Could someone explain more about BTS50055?

I'm just not sure if it can drive motors too because I was told that it can replace a MOSFET to simplify the circuit. I don't quite understand how.

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The BTS50055 is not good for fast PWM. If you look at the data sheet in particular "load switching capabilities and characteristics" on page 3 it tells you how fast the device can switch. Turn on time is somewhere in the 100us range typically and turn off might be about 60us. These numbers need to be 1% or less for decent efficiency and 100us represents 1% of 100Hz. If your switching speed is pretty low then use it.

How can I design a MOSFET H-bridge motor driver controlling only 1 PWM for a motor?

If I understand correctly you have a single PWM signal and you want to drive a H bridge with this signal. I'd start by looking for a couple of beafy N channel mosfets like the IRF1010 and then pick a topside/lowside mosfet driver like LTC4444. Feed PWM to the inputs via a couple of logic gates that create a deadband (so both FETs never switch on at once) and this gives you a half H bridge.

Repeat to make the other half but remember to invert the PWM signal. I'd look to be monitoring current on the dc side of things and forget about the BTS50055.

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the problem it's designed to solve is: how do you drive an N-FET which needs a gate voltage near its drain to shut it off and a voltage a bit higher to turn it on when the source voltage is 20-50v or so and you're driving it from 3-5v logic, and the drain voltage jumps up and down as you switch it on/off?

to make an H-bridge you'll need 2 of these and 2 more N-FETS on the ground side - and be very careful about never driving a short through them

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