I am trying to run a small servo, MG90S, using an ESP32 development board.
I read the stall current is 700mA, so I bought this small boost converter on Amazon, rated to 5V and 1A.
https://www.amazon.com/dp/B091CRCZ65?With no load, I noticed the servo was occasionally glitching.
I hooked up my scope, and measured 800mA peak.
However, 3ms after the load ramps down, the 5V output shoots up to 7V for 1 ms, before coming back down.
I tried adding a 10uF capacitor on both 3.7V, as well as 5V. But the problem is still there.
Is there something else I can do, or a suggestion of a small simple boost converter for my application I can buy?
Edit:
Also, I see "4R7" on the inductor on the board. Given this is 4.7uH, then the energy should just be 1/2*4.7uH*(400mA)^2 = 4.7uJ
If I wanted to make sure the voltage does not overshoot above 6V, if the load is suddenly disconnected, then 1/2*C*[(6V)^2 - (5V)^2] = 4.7uJ will calculate the minimum capacitance? I calculate C = 6nF.
So it does not seem like there is insufficient capacitance to soak up the energy. The converter itself isn't responding for some reason and continues switching..?