-50% 100 PZ 1/2 W diodo Zener 0.5 W 2.2 V ~ 30 V BZX55C2V2 BZX55C2V4 BZX55C2V7 BZX55C3V0 BZX55C3V3 BZX55C3V6 BZX55C3V9 BZX55C4V3