Voltage drop when I put load on PWM pin in my jetson nano

I am working with the Jetson nano PWM channel. When I generate PWM it is working perfectly but when I put a load on the PWM channel pin, the voltage drops down by 3.3V to 1.5V.

Is there any way to stable my voltage according to my PWM for example, at 100% duty cycle voltage is 3.3V, and at 50% duty cycle my voltage is 1.5V.

Thanks,
Ridham.

Hi, is this pin one of the 40-pin header? If so, there are some requests to its load as below app note listed.

You can search “jetson-nano-developer-kit-40-pin-expansion-header-gpio-usage-considerations-applications-note” in DLC too.

Hello Trumany,
I go through your reference, and it works for me. Thank you.

Ridham.

Hi Trumany,

I used 2 PWM in jetson nano one is for 12V DC LED and the second one is for a 12V DC stepper motor. Pin no 11 is for direction. When both PWM runs and the direction is 1(3.3V), the light is not working properly, and when the direction pin is 0(0V) light is working perfectly.

Please give me some suggestions for that.

Thank you,
Ridham

Don’t get what you mean. Have you checked the real signal to make sure it fits the request of your LED? Can you share the schematic or diagram of your setting?

Hi Trumany,

Sorry if you don’t understand. I use 12V DC LED and 12V DC Stepper Motor in my project. Both work on the PWM channels from Jetson Nano (Pin 31 & Pin 32). Also, I am using Pin 11 for the stepper motor direction (Pin 11 = HIGH, Motor in forward & Pin 11 = LOW Motor in Reverse). Another thing to mention is that for 12V LED and 12V DC Stepper runs with the help of a PWM signal.

My problem is that when I am using both PWM simultaneously and put the motor in forward (Pin 11 = HIGH) the LED is not working correctly but when I put my motor in reverse (Pin 11 = LOW) the LED start blinking.

For your understanding:
condition 1:
pin 32 (led is on via PWM. 1000HZ frequency)
pin 33 (motor is rotate via PWM. 15kHZ frequency and 50% duty cycle)
pin 11 (for direction pin high 3.3V)
Result: LED is not working

condition 2:
pin 32 (led is on via PWM. 1000HZ frequency)
pin 33 (motor in rotate via PWM. 15kHZ frequency and 50% duty cycle)
pin 11 (for direction pin low 0V)
Result: LED is working

Anything that I need to do with the code or it has some other issues?
Please suggest some solution for the same.

I have also attached a block diagram for your reference.

Thank You,
Ridham.

What is pin 11 doing here? Does it expect to work as GPIO? If so, are you sure you configure it in gpio mode?

Also, why highlight “two pwm” in this topic? Will the LED work if only one PWM is in use?

  1. Pin 11 is configured just as GPIO and used for the direction of the motor.
  2. One PWM is used for MOTOR and another for LED Dimming.

Also, I explain every logic in the above thread please go through it for a better understanding.

There is no update from you for a period, assuming this is not an issue any more.
Hence we are closing this topic. If need further support, please open a new one.
Thanks

Sorry that I cannot get the logic here. Could you just tell me what is your expected result?

Is the GPIO in input mode or output mode?

Why is a GPIO related to the LED PWM? Or that is the question you want to ask?