Active production — 13 V zener, 500 mW, DO-35 axial
The 1N6003C: The ±2% tolerance on the nominal zener voltage makes this part suitable for voltage reference applications where a standard 5% zener would drift outside the regulation window.
Leakage and impedance — the real-world operating margins
Reverse leakage is specified at 100 nA maximum at 9.9 V reverse voltage — that is 76% of the nominal zener voltage, so the diode stays below 1 µA leakage even near the knee, preserving battery life in always-on sense circuits. Maximum zener impedance (Zzt) is 25 Ohms at the test current — a moderately low dynamic resistance that keeps the voltage regulation within a few hundred millivolts across the rated load current swing for a 500 mW part. Forward voltage drop is 1.1 V maximum at 200 mA forward current — useful if the diode is also used as a low-current rectifier or flyback clamp in the same BOM position.
Package and board-fit — DO-35 axial form factor
Supplied in bulk — no tape-and-reel — so the part is typically handled in low-volume assembly, prototyping, or rework where a cut-tape or individual tube presentation is preferred.