LM2577T-12 LM2577T-12/LB03 LM2577T-12/LF03 LM2577T-12/NOPB LM2577T-12V LM2577T-15 LM2577T-15/LB03 LM2577T-15/LF03 LM2577T-15/NOPB LM2577T-3.3