Tool/software:
Hi support team,
I have a question about the LMR43620MB5RPER.
When using FB resistors with this device, does it output a VOUT equal to the FB resistor setting, and does it output 5 V if VOUT is directly connected to the VOUT/FB pin?
Regards,
Dice-K
Hi Dice-K,
Yes. This device has an internal feedback divider that will set the output voltage such that if FB is directly shorted to the output side of the output inductor, the device will operate with its fixed voltage (in this case 5 VOUT).
When using a FB resistor ladder, it will output the VOUT equivalent to the VOUT set by that ladder. Due to the internal FB divider, the resistor ladder must follow the requirements as outlined in section 9.2.2.2.1 of the datasheet. I have included the relevant excerpt from the datasheet for your convenience below:
Thank you,
Joshua Austria
