![]() That means that this H-bridge cannot be run at 0% or 100% duty cycle. This isn't very good, but it says: "The bootstrapping method for achieving the high mosfet gate voltages avoids the need for an additional DC to DC power supply, but for the bootstrapping to work, there needs to be time to recharge the bootstrapping capacitor. If you're going to switch the top FET on for a bit, you have to first start with the lower FET on so that the boost cap is charged to ~12V, when Vs then goes high the top of the cap goes above 12V to supply the >12V for the top FETs gate through HO. "they clearly state: motor control in one of their applications" Yes but every FET H bridge that google has found so far is continuously switching between high and low. I have enough parts to make 1 new board but that's pretty much it.Thank you very much. (both EN1 and DIR1 are 3.3v signals,DIR1 is digital High/Low, but EN1 is a PWM VCC is 12v and VDD is not being utilized here but it would be 3.3) I was wondering if you guys can help me troubleshoot this issue and perhaps get this board working. I've created this exact same circuit 3 times and I'm running out of them but I've had no luck finding what the problem is. I checked a few volrages and the Vs is sitting at around 9.5v with respect to ground (drops quickly to 7.8 volts when measured by a multimeter or oscilloscope) but the voltage across both tantalum capacitors is 0. ![]() I have tried it with a DC motor and a 5k resistor connected to the load, no chance with either of them. I checked everything and found out I'm missing a connection here: I just botched a few wires to make that connection but it still wouldn't work. HO on the U1 and LO on the U2) and this is the arrangement of H bridge itself after ordering the parts and the PCB, I started testing it, but I had no luck and it wouldn't work. I went with the suggested circuit as provided in the gate driver datasheet I just used a transistor to invert the IN signal to the second chip, so the opposite mosfets turn on (e.g. I used the FDMC7696 for both high side and low side mosfets. ![]() I designed an H bridge using the DGD0506A gate drivers. ![]()
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