LM2940T-13+ LM2940T-13+.0 LM2940T-3.3 LM2940T-5 LM2940T-5.0 LM2940T-5.0 电源IC LM2940T-5.0/LF08 LM2940T-5.0/NOPB LM2940T-5.0/NOPB . LM2940T-5.0+