What is this IC?

Trying to find a datasheet for it. Best I can make out from markings is:

LB 21 

Package: SOT-89-3

Photo of IC


1 Answer 1


It is a LM317LIPK from Texas Instruments (marking "LB", "21" is a datecode).

Picture from lcsc:

enter image description here

  • \$\begingroup\$ looks like that but its 21 not 84 \$\endgroup\$ Commented Jun 17 at 16:23
  • 1
    \$\begingroup\$ same component, different date of manufacturing (date code) \$\endgroup\$
    – vivier
    Commented Jun 17 at 16:29

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