Can this drive circuit work at 5KHZ?

飞絮

Can this drive circuit work at 5KHZ? [Copy link]

I have a project that requires driving a 2A load at a working frequency of 5KHZ. I plan to use the following circuit, but I wonder if it can reach a frequency of 5K.

Fred_1977

Does your load change with the frequency?

maychang

"I am going to use the following circuit, but I wonder if it can reach 5K frequency."

Just based on the 4.7k resistor of R3, the 5kHz square wave will definitely have tilted edges.

maychang

If you want a similar circuit to work at a higher frequency, the rising and falling edges of the current in the MOS tube must be steep enough, and the driving circuit cannot use a resistor to pull up, it must be a push-pull circuit (both pull-up and pull-down rely on transistors).

maychang

The driving voltage used in this circuit is less than 6V, which is a bit too low. It is better to reach 8~9V. Otherwise, the MOS tube may not be fully turned on. You can see this from the manual of IRF540.

飞絮

Thank you for your replies. I have switched to using a dedicated circuit to drive the MOS tube. I think it is not feasible to simply drive high-frequency loads in this way.

Gen_X

maychang published on 2021-12-24 20:40 The driving voltage used in this circuit is less than 6V, which is a bit too low. It is better to reach 8~9V. Otherwise, the MOS tube may not be fully turned on. For this, look at the IR ...

This is good advice!

fjdeepblue

6N137 is a high-speed optocoupler, 5K is no problem, it is mainly MOS driven, and needs to be changed to push-pull drive.

xutong

It's not a big deal to make the pull-up resistor smaller. Do you need a very steep edge?

振动试验仪器

The circuit of the driver board of the power amplifier used in the vibration test bench can be used as a reference. Use 6N137 to isolate the input, and after being buffered by 74LS06, the push-pull circuit composed of 2N2222 and 2N2907 can drive the 540 MOS tube.

振动试验仪器