12/11/2022 0 Comments H bridge with mosfet![]() When S2 and S3 are closed the motor gets power and spins in the other direction. When switches S1 and S4 are closed the motor gets power and spins. The circuit consists of four switches which complete the circuit when applied in pairs. The H-Bridge is given it's name based on the basic circuit which demonstrates it's operation. This is easily demonstrated by applying a 9-volt battery to the leads of a small motor and then switching the terminals to change directions. The motor direction is changed by switching the polarity of the voltage in order to turn the motor one way or the other. This will continue until the current has decreased to 0, at which point the capacitor will start discharging and current will start flowing in the opposite direction.The H-Bridge is a circuit which can drive a DC motor in forward and reverse. It follows that if you want to reverse the current very quickly, you must minimize inductance and maximize voltage.Īlso bear in mind that when you change directions on the H-bridge, the inductor will reverse the direction of current in the capacitor and charge it. This is a fundametal property of inductors: The rate at which you can reverse the current in L1 is limited by the inductance and the voltage you can apply to it (in this case, determined by C1). There will be current in the diodes only transiently as the H-bridge is changing states, so depending on how fast the switching is, and what the current in that time is, you may remain within the MOSFET's operating parameters. Note that the diodes drawn need not actually be diodes, they can be the inherent body diode of the MOSFETs if your design parameters allow. Also you could consider a discrete driver. ![]() If switching speed is not critical, you may be able to the MOSFETs directly with a microcontroller.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. Archives
December 2022
Categories |