Servo jitter, shake. xiao nrf52840 sense

Products & Technology XIAO
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1

Hello.

Please help me.
microcontroller Xiao nrf52840, servo feetech FT1109M connected to pin 5 and external power supply 5V 5A
a simple code:
#include <Servo.h>
Servo servo;
void setup() {
servo.attach(D1);
}
void loop() {
servo.write(100);
}

The servo rotates to the specified angle and shakes. If I connect the servo to the arduino nano, there is no shaking, everything works fine. Why does the servo shake when connected to the NRF52840 sense?

2

Hi there

And welcome here…

The Nano works because it outputs 5V PWM that the servo expects. The Xiao doesn’t. A logic level shifter or an external PWM driver (like PCA9685) will make it rock solid.

    • nRF52840 GPIOs are 3.3V, while Arduino Nano uses 5V logic.
  • The FT1109M servo is designed for 5V control signals. It may not reliably interpret the 3.3V PWM from the Xiao as a “clean” HIGH signal, especially under load.
  1. Grounding or Current Surge Issues
  • Even with a 5V 5A supply, ground must be shared between the Xiao and the servo power supply.
  • If not shared, the signal reference floats, leading to misinterpreted PWM edges.
  • Also, servo motors create voltage dips/spikes; Xiao may not tolerate that as well as the more forgiving Arduino Nano.

HTH
GL :slight_smile: PJ :v:

Confirm that GND from the Xiao is tied to GND from the servo power supply. :+1:

3

I have no issues driving the FeeTech (and similar) Servo modules with ESPs, NRFs and MG24s.

While the operating voltage is 4.6-6V the signal voltage is 3-8.4V

I would however recommend the use of the NRF library… eg
#include “NRF52_ISR_Servo.h”