I have issue with this device.
(1) TPS76901-EP quoted internal reference as 1.124V
(2) TPS76901-Q1 quoted internal reference as 1.224V
The TPS76901-EP was shipped from Digikey for pre-production qualification test (next year it will be volume production),
I have fitted the TPS76901-EP on board with R2 = 150K and R1 = 249K which provide 3V3 (based on Q1 datasheet). I get 3V0 rather than 3V3 (or 3.26V).
I also get 3V0 into 1K load.
I build a breadboard with nothing on circuit except the TPS76901 and have 1uF cap on VIN and VOUT. I use VIN = 5V from bench PSU. It confirm 3V0 output for all three devices. The equation in datasheet (Q1) say it should be 3V3 but uncertain which VREF is correct.
I check the FB pin and measured 1.20-1.21V (that with 1K load). (NB: there is possibility of DVM loading effects).
In order to make O/P to 3.3V, I adjusted the R1=270K and it seem stable over the load to 50mA.
Q1: Is this device defective, has the internal VREF set incorrectly or ?
Q2: Can you confirm which is correct VREF voltage between EP and Q1 as this is confusing?
