I would modify this circuit to deliver about 1.2A max. To do that, the voltage divider has to deliver 1.2V to the op amp pin 3, when 5V is input. R1=3.3K, R2=1K should produce about 1.16V. The valve drive and op amp power supply voltage must be greater than about 8V. 10-12V should be OK but you will need a heat sink on the power transistor.
Hi,You will need a PWM frequency of 1.2kHz.
Is there a way to suppress this sound?
Datasheet don't say anything about suitability for PWM or whether dither is needed. Good luck.
Hi,Good to see you have a result.What are you using as a power supply for the solenoid?Can you post a copy of your circuit diagram please?
No, but you could try different PWM frequencies.For the new coil, you have to change the circuit constants to result in 165 mA max = 16.5V across a 100 Ohm coil. Study the design hints in reply #14.That cannot be done without a higher voltage power supply, say 24V.
I don't understand why the current value corresponds to voltage (0.165A to 0.165V).
R1 = 10K, R2 = 340 Ohms to deliver Vout = 0.165V
Ohm's Law. V=IR
You could also increase the value of the current sense resistor, for example to 10 Ohms, leading to 1.65V for 0.165A through the coil, and then use the original voltage divider.
In#22, both coils can't have same resistance but still their Vouts are similar to output current. Doesn't make sense to me.
I hope I explained that clearly enough.
In both cases you have a 1 Ohm sense resistor, producing a voltage proportional to the coil current, according to Ohm's law.
I used FQP30N06L instead.Its a logic level N-Channel MOSFET with Vgs lower than 3V.