7.5 V regulation with 1 W thermal budget
The 1N4737AP/TR8 is a 7.5 V Zener diode from Microchip Technology's 1N4737 family, rated for 1 W continuous power dissipation in the DO-204AL (DO-41) axial-lead package. The ±5% tolerance on the nominal 7.5 V Zener voltage means the actual regulation point sits between 7.125 V and 7.875 V at the specified test current — a figure to budget into the output rail tolerance for the downstream load. Maximum Zener impedance is 4 Ohms (Zzt), which defines the incremental resistance at the operating point; a lower impedance gives tighter regulation as the load current varies, and this value is typical for a 1 W device at this voltage.
Temperature range and leakage
Reverse leakage is specified at 10 µA maximum with 5 V reverse bias — well below the Zener knee, so standby power loss in a reverse-biased shunt configuration stays under 50 µW per diode. Forward voltage drop is 1.2 V maximum at 200 mA forward current, a parameter that matters if the diode sees brief forward conduction in a bidirectional clamp topology.