TLV758P: Dropout voltage on my customer's condition.

Hey Hattori, 

From the EC Table: 

For Vout=1.35 and using the worst case of Vdo=400mV @500mA

Then Rds=800mOhms

For Vout=1.35V @ 300mA then Vdo=240mV.

Your Vin must be within 1.59V. Therefore, using 1.8V would give you 450mV of headroom. 

Best, 

Edgar Acosta