PDF datasheet of 85.9 KB covering the 1N5221 through 1N5279B zener diodes, indexed under schematics. The B in the range name points to the tolerance grade documented. Use the voltage table to identify a failed zener from its marking, check the expected breakdown voltage during testing, or choose a suitable substitute. Any PDF viewer will display it. Pay attention to tolerance letter, power dissipation and the cathode band, and note that data from different vendors may differ slightly in test conditions.
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