SNVS771C May 1998 – December 2016 LM138 , LM338
PRODUCTION DATA.
The input supply to LM138 and LM338 must be kept at a voltage level such that its maximum input to output differential voltage rating is not exceeded. The minimum dropout voltage must also be met with extra headroom when possible to keep the LM138 and LM338 in regulation. TI recommends a capacitor be placed at the input to bypass noise.