SNVSBB0A May 2019 – November 2019 ATL431LI-Q1 , ATL432LI-Q1
PRODUCTION DATA.
The ATL431LI-Q1 requires an input resistance in this application to source the reference current (IREF) needed from this device to be in the proper operating regions while turning on. The actual voltage seen at the ref pin is VREF = VIN - IREF × RIN because IREF can be as high as 4 µA. TI recommends to use a resistance small enough that mitigates the error that IREF creates from VIN.