5.1 V regulation at 1 W
The 1N4733AP/TR8 is a 5.1 V Zener diode rated for 1 W continuous power dissipation in the DO-204AL (DO-41) axial-lead package. The ±5% tolerance means the actual breakdown voltage falls between 4.845 V and 5.355 V — tight enough for basic shunt regulation or as a reference in a low-cost supply, but not precise enough for a band-gap-grade voltage reference.
Zener impedance and leakage
Maximum Zener impedance is 7 Ω at the test current (Zzt). This impedance determines how much the output voltage shifts under load: a 10 mA change in Zener current shifts the voltage by roughly 70 mV. Reverse leakage is specified at 10 µA maximum at 1 V reverse bias — well below the breakdown knee, so the diode draws negligible current in the off state. Forward voltage is 1.2 V maximum at 200 mA forward current — a useful number if the diode is occasionally forward-biased in a protection or clamping role.
The DO-41 axial-lead package is through-hole mounted — the leads are soldered into plated through-holes on the PCB, making it suitable for prototyping, rework, and builds where vibration resistance is less critical than board-level repairability.