Mosfet bridge driver

I think the module wants stable low PWM and direction inputs at startup, so i have to make sure to turn on its power supply before I start the micro controller providing the PWM and DIR inputs.

Because of this, I had to add a filter section with 47uH inductors and uF capacitors between the motor driver and the thermoelectric cooler module. Tccpa Mosfet Driver One small annoyance has shown up--I have to be careful about power sequencing at startup. I have built the circuit attached herein on a PCB. The driver section and the half-bridge circuit were tested individually and worked fine. But when I try to combine them the IR always blows up. And the output of the 12v supply that I used to power the vcc pin of the IR gets messed up as well.

I used 80v ac coming from a variac. How do I fix this problem? This appears to be the main disadvantage of a 4 channel MOSFET based H-bridge topology, that common users find difficult to configure and implement. An alternative approach to making an easy and universal H-bridge driver module that promises high efficiency and yet gets rid of the complex bootstrapping is by eliminating the two high side N-channel MOSFETs, and replacing them P-channel counterparts. One may wonder, if it's so easy and effective then why is it not a standard recommended design?

The answer is, although the approach looks simpler there are a few downsides which may cause lower efficiency in this type of full bridge configuration using P and N channel MOSFET combo. Second danger may be a shoot-through phenomenon, which can cause an instant damage to the devices. That said, it is much easier to take care of the above two hurdles than designing a dicey bootstrapping circuit.

The working of the above H-bridge design is pretty much basic. The idea is best suited for inverter applications for efficiently converting a low power DC to mains level AC. The 12V supply is acquired from any desired power source, such as from a battery or solar panel for an inverter application.

The supply is conditioned appropriately using the uF filter capacitor and through the 22 ohm current limiting resistor and a 12V zener for added stabilization. The stabilized DC is used for powering the oscillator circuit, ensuring that its working is not affected by the switching transients from the inverter. By default, the BC transistors are in the switched ON condition, through their respective base resistive divider potentials. In this situation, the load at the center, which is a transformer primary winding gets no power and remains switched OFF.

When clock signals are fed to the indicated points, the negative signals from the clock pulses actually ground the base voltage of the BC transistors via the uF capacitor. Learn more about using timer in astable mode here. This circuit can be replaced by any other PWM source like an Arduino. The gate driver is a standard two-channel TC , with 1. Here, both the channels have been paralleled for more driving current. Again, if the frequency is higher the gate driver needs to be more powerful.

This is the working part of the circuit that controls the motor. The biggest advantage of this circuit is that it can be scaled to drive motors of all sizes, and not only motors — anything else that needs a bidirectional current signal, like sine wave inverters. When using this circuit even at low powers, proper localized decoupling is a must unless you want your circuit to be glitchy. Also, if constructing this circuit on a more permanent platform like a PCB, a large ground plane is recommended , keeping the low current parts away from the high current paths.

So this simple H-Bridge circuit is the solution for many motor driving problems like bidirectionally, power management and efficiency. Nice idea for learning H-bridge circuits, your logic is right on; some major things you may have missed.

With your circuit as shown this will happen at the transition where one is turning on the is turning off. Examine the Vgs of both upper and lower devices over the full gate voltage swing. You will fine you have them both in the partially enhancement mode where both are trying to conduct. The slower the rise and fall time of the gate the worse this will be. This will create some huge current spikes.

What is shown on the breadboard will work because of the limiting impedance of the interconnections. The primary failure will be either shoot through or VGS over voltage.