LMP91000: configuration of C1 and C2 pin

Part Number: LMP91000

Tool/software:

Hello team,

Please review the schematic of LMP91000 and provide the feedback and also what is the use of C1 and C2 what needs to be connected in schematic.

  • Hi Darshan,

    A few notes:

    • Do you have pull-up resistors for SCL & SDA?
    • What is the purpose of the resistor in series with the VREF pin?

    Otherwise looks good.

    The purpose of the C1 and C2 pin is to add an external gain resistor or an external capacitor for filtering. These pins connect across the feedback of the transimpedance amplifier inside the LMP91000. It is not necessary to connect anything to these pins. The LMP91000 comes with programmable TIA gain options, and you would only connect an external gain resistor if those options were not satisfactory. Adding a filter to C1 and C2 is optional as well, and would be needed only if there is noise on the Vout pin.

    Thanks

    -Alex Thompson