SLVS905B December 2008 – July 2024 TLV431A-Q1 , TLV431B-Q1
PRODUCTION DATA
TLV431 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 will be Vref=Vin-Iref*Rin. Since Iref can be as high as 0.5µA TI recommends using a resistance small enough that will mitigate the error that Iref creates from Vin.