The 1N4744CPE3/TR12 is a 15 V Zener diode from Microchip Technology, rated for 1 W continuous power dissipation in the standard DO-204AL (DO-41) axial-lead package. The ±2% tolerance on the nominal 15 V zener voltage means the actual breakdown sits between 14.7 V and 15.3 V at the specified test current — tight enough for a 15 V rail clamp or a low-voltage reference where a standard 5% part would drift outside the design window.
Thermal and impedance profile
Maximum zener impedance is 14 Ω at the test current — this sets the dynamic resistance the regulator or clamp sees; a 10 mA load step shifts the output by 140 mV, which is predictable for a shunt reference but matters if the load is a sensitive ADC reference input. Reverse leakage is specified at 5 µA maximum at 11.4 V, well below the zener knee — a useful check for standby power budgets where the diode sits across a rail and must not drain the supply before the zener conducts.
Supplied in Tape & Reel (TR) packaging, the reel quantity suits automated insertion equipment for volume builds; the axial leads are taped per EIA-296 standard for radial or axial component feeders.