5.6 V zener with tight regulation window
The 1N4734CPE3/TR12 is a 5.6 V zener diode from Microchip Technology's standard reference family, rated for 1 W continuous power dissipation in the DO-204AL (DO-41) axial-lead package. The ±2% tolerance on the nominal voltage gives a regulation window of roughly 5.49 V to 5.71 V, tighter than the common 5% grade — useful when the downstream circuit needs a stable reference or clamp threshold without trimming.
Thermal and impedance profile
Maximum impedance (Zzt) is 5 Ohms at the zener knee — this is the dynamic resistance the diode presents when conducting at its test current. A lower impedance means the voltage stays flatter across the operating current range, which matters when the zener serves as a shunt regulator or voltage reference in a bias supply. The 1 W power limit in the DO-41 body means the junction-to-ambient thermal path through the axial leads and PCB copper sets the real-world derating — at 25°C ambient the full watt is available, but above that the allowable dissipation drops linearly per the datasheet derating curve. Reverse leakage is specified at 10 µA maximum when 2 V is applied across the junction — this is well below the zener voltage, so the diode is in the off-state. The low leakage keeps standby current negligible in battery-powered circuits where the zener sits across a rail as overvoltage protection. Forward voltage drop is 1.2 V maximum at 200 mA forward current — a standard silicon junction characteristic. If the part is used in a bidirectional clamp or as a general-purpose rectifier in a pinch, the forward conduction loss at 200 mA is about 240 mW.
The DO-204AL (DO-41) axial package is a through-hole format with 0.025-inch diameter leads on 0.300-inch nominal lead spacing. It inserts into standard 0.040-inch PCB holes and is wave-solder compatible. The Tape & Reel (TR) packaging option feeds into automatic insertion equipment for volume assembly.