Prince Charming
Member level 2
Hello, I've been building a full H bridge with Arduino and I need 2 separate PWM signals one of which will trigger the first couple of MOSFETs and the second one will trigger the second couple. I found doing it in Arduino unreliable and I didn't want to write a separate code for it so I wanted to do it with analog electronics. Below is my circuit:
Basically when pin10 is 5V, Q1 activates and makes the !pin10 0V and when pin10 is 0V then the voltage divider makes !pin10 5V. pin10 and !pin10 trigger IR2110. I wanted to turn the MOSFETs on with a delay because they will probably take some time to turn on and if two couples are on at the same time this will cause a short circuit. I assumed around 200ns delay is enough. C1(4.7pf) and R2(10k) will generate a delay for !pin10. The delay on pin10 will be created by the C2 and R4. When the !pin10 is high Q4 will discharge the capacitor C2 and make it ready to delay the next signal.
The capacitors will probably have enough time to discharge as my maximum switching frequency will be 60Hz.
I need assistance with the circuit in general and also I want to choose fast switching parts for diodes and transistor. If you can advise me some of the fastest transistor and diodes I would be glad.
One more thing is, the purpose of Q6,C3 and R5 is to stop !pin10 output if no signal comes from Arduino for some time (around a second, I can increase it to 3 seconds to make sure it won't cut too early).
H bridge circuit if you are wondering:
Well I've just noticed that I have no control over duty cycle of the negative half phase with this circuit that's why it is wrong. But still let's consider I needed a PWM signal with duty ratio of 1, would it work?
Thanks.
Basically when pin10 is 5V, Q1 activates and makes the !pin10 0V and when pin10 is 0V then the voltage divider makes !pin10 5V. pin10 and !pin10 trigger IR2110. I wanted to turn the MOSFETs on with a delay because they will probably take some time to turn on and if two couples are on at the same time this will cause a short circuit. I assumed around 200ns delay is enough. C1(4.7pf) and R2(10k) will generate a delay for !pin10. The delay on pin10 will be created by the C2 and R4. When the !pin10 is high Q4 will discharge the capacitor C2 and make it ready to delay the next signal.
The capacitors will probably have enough time to discharge as my maximum switching frequency will be 60Hz.
I need assistance with the circuit in general and also I want to choose fast switching parts for diodes and transistor. If you can advise me some of the fastest transistor and diodes I would be glad.
One more thing is, the purpose of Q6,C3 and R5 is to stop !pin10 output if no signal comes from Arduino for some time (around a second, I can increase it to 3 seconds to make sure it won't cut too early).
H bridge circuit if you are wondering:
--- Updated ---
Well I've just noticed that I have no control over duty cycle of the negative half phase with this circuit that's why it is wrong. But still let's consider I needed a PWM signal with duty ratio of 1, would it work?
Thanks.
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