Switching power supply drive circuit
Posted on Dec 11, 2010 5493
Driver circuit diagram: The main function of the driving circuit is variable width pulse width controller output power amplifier, as a drive signal to high voltage power switch
ing device. Driving circuit generally have a role in isolation, often coupling transformer to achieve the high-voltage power switching devices incentive isolation between the input and output stages and, while both when the power switching device is turned off, reverse bias is applied, to accelerate the device on and off. When the drive MOSFET device, a conventional drive circuit is driven by a transformer to achieve. Taking into account the leakage inductance and lead inductance drive transformer to the main MOSFET having a large Cg-s high-speed charging and discharging cause difficulties, therefore, the usual way is to use a MOSFET driver drive transformer having a smaller Cg-S of the totem type driving circuit then this circuit driven by the main MOSFET. As shown, the drive transformer primary input is the output signal of the drive signal control circuit, the output after shaping circuit shaping process after isolation transformer. Transformer isolators, optocouplers isolate both have anti-interference function, after shaping by Totem drive circuit drives the main MOSFET tube.