3.3V Step-Up/Step-Down Voltage Regulator S9V11F3S5

I’m using this regulator to step down 6v to 3.3v, however, from Vout I am reading a constant 4.85v. There is no load on the circuit… I just connected a 6v battery to “gnd” and “in” on the regulator. When I use my multi-meter to measure from “gnd” to “out” is when I get the 4.85v reading. Any ideas on why it isn’t 3.3v?


Could you post pictures of your test setup that show both sides of the board and all connections including the soldering? Have you ever gotten 3.3V out? Have you ever connected the output to a load?


Here is a link to some pictures of it. (They were to big to upload) I never got 3.3v out of it. It has always been 4.85. Never connected a load to it because 4.85 is to much for what I’m powering. (rfduino that requires 3.6v max) Thank you!

Thanks for the pictures. Your connections look okay and I was able to check that based on the resistors populated that you do have the 3.3V version of the regulator. It might be that the internal pull-down resistor on the SEL pin is not connected well. Could you try connecting the SEL pin to ground and see if the output changes?


I connected SEL to ground and I’m getting the exact same 4.85v reading. Is it possible to send me another regulator?

Since connecting SEL to ground did not work, it seems the regulator is probably damaged, though I did not see any physical signs of it on the board. Please email us at support@pololu.com with a reference to this thread and your order information and we will see what we can do.