MPM3632S, R4 and max capacitive load

Dear mps Tech-team,

we are using MPS3632S in our design, could you please let me know the answer for below question:

  1. which tolerance for R4 (connected from VOUT to OUT_S) is your recommendation ? what’s the purpose of adding R4?
  2. is there a maximum capacitive load for of this regulator?

thanks a lot.

Highly appreciate for a qucik response.

Chen

Hi Chen,

Thank you for contacting the MPS Forum. I’m looking at your question and will work on getting you an answer soon.

Thanks,
Brendan Schoemehl
Field Applications Engineer
Monolithic Power Systems | MPS Now

  1. We recommend using a 1% tolerance of R4. The purpose of this resistor is usage as a sense resistor in order to aid in the output sense function of the device. We are essentially connecting the output to the internal ramp through a series resistor based on Figure 1 of the datasheet.

  2. This device is a COT device, meaning too much output capacitance on this device will ruin the operation and regulation of this device. While there is no stated output capacitance max value, I would recommend about 66uF max with a 0.1uF decoupling cap, where 44uF + 0.1uF is perfect for typical applications.

Thanks,
Brendan