I need to use a 5V, 40mA signal to activate a 25V, 10A H-bridge circuit. Is there some kind of high-power logic buffer out there for this kind of difference?
Standard issue high/low driver IC. I use IR2110 IC's and they can drive 1200V 600 amp IGBT's using a 3.3 or higher logic level input.
Driving Mosfets or IGBT's to switch 25 volts at 10 amps would be no problem for them!
I would go with birdmans idea first. the IR2110 are best suited to high gain transistors and voltage controlled devices like Mosfets and IGBT's.
Given the low cost of logic level Mosfets in the 60 volt 10 amp range they would be a far better choice.
I would recomend one rated for >50V and > 20A might as well double your requirements
I can't do all the work for you find a part and we can have a look
You will need both N-channel and P-channel
Look up a H-brige mosfet circuit.
N-channel is tied to ground and P-channel to V+
N-channel should be pulsed with the PWM because they generally have a lower Rds
Look up a H-brige mosfet circuit.
N-channel is tied to ground and P-channel to V+
N-channel should be pulsed with the PWM because they generally have a lower Rds