Hello, I had previously inquired about using the MPM3695-10 for generating a 0.95V output using a 3.3V input (link here MPM3695-10 Vin=3.3V - #4 by Krishan.FAE )
I received my boards yesterday. The 0.95V output does not come up. I connected the VCC pins to an external 3.3V supply (same 3.3V supply connected to VIN). There is no dips in the 3.3V output, and the PWRGD_P3V3 is 3.3V. Is there something wrong with the design? The schematic is below:
Well sure something is wrong. Shouldn’t there be a pullup on the TAKE pin for instance. It seems that is the signal to get it started.
R1 is the pullup for TAKE_0V95. Pulled up to 3.3V
Do you have an EVAL board, is this your first time with this chip? Is the I2C hooked up? Can you talk to the chip
No, I do not have an EVAL board.
Yes, this is my first time using this chip.
No, I don’t have I2C connected.
What is the voltage at the CTRL pin?
3.3V. It is coming from the PWRGD pin on the 3.3V power supply. And it is up and working.
Well I am out of ideas, maybe someone at MPS could help. Have you compared your layout to the EVAL board layout?
I appreciate the help! Yes, it compares to the EVAL. I have another MPM3695-10 on board that is outputting the 3.3V from a 12V input. The same layout is used on that and it is working great.
Faulty component, solder bridge? Not even a wiggle?
I have 2 boards doing the same thing. Checked all component values, soldering, etc…
