Hi all !
I'm here because i'm facing a problem where i'm running a board on which i have 2 big servos (17kg/cm).
Firstly, let me tell you that i'm a noob in electronics.
Let's say, i'm beginning in switching regulators.
Until now, everything was running fine but suddenly, it seems that my +5V is unstable.
My voltage regulation is based on a "LM2576T-5.0 P+".
Symptoms :
- When i plug the +12V on my circuit, it refuses to power on everything until i disconnect the 2 servos.
- If i plug one of the servos, then everything powers off (protection mode of the LM2576 i think)
- When the system is not powering on, if i mesure the normally +5V, it is +1,95V.
- The system won't handle load correctly (if it goes further than 1A, it resets like power is cut then back on then cut then back on etc ...)
I have 2 feelings :
- The inductor (100µH) seems to be a 1/2w (you know the axial ones ; green color ...) ; i think i made a big error when buying it because it is clearly not supporting 3A !
- Could it be the LM2576T-5.0 which was running without heatsink and i don't know if it has suffered from high temperature of today as my circuit is located outside in a closed box of approx. 30cm X 20cm X 10cm. (I did a calculation of the heat sink and it seems it requires, for 3A, a 20°C/W heatsink ; but as it is not running 3A frequently, i thought it was useless to add a heatsink for now ... finally, maybe not)
Hope to have good advices ! Thanks !