|GLASS PASSIVATED JUNCTION SILICON ZENER DIODES
Built-in strain relief Low inductance Typical ID less than 1.0�A above 11V Plastic package has Underwriters Laboratory Flammability Classification 94V-O High temperature soldering 260�C /10 seconds at terminalsPb free product are available 99% Sn can meet RoHS environment substance directive request
Case: JEDEC DO-214AA, Molded plastic over passivated junction Terminals: Solder plated, solderable per MIL-STD-750, Method 2026 Polarity: Indicated by cathode band Standard packing: 12mm tape (E1A-481) Weight: 0.003 ounce, 0.093 gramRatings at 25�C ambient temperature unless otherwise specified.
Parameter Peak Pulse Power Dissipation TA=50O C (Notes A) Derate above 70O C Peak Forward Surge Current 8.3ms single half sine-wave superimposed on rated load (JEDEC method) Operating Junction and Storage Temperature Range Symbol Value + 150 Units W atts mW/ O C Amps
NOTES: A.Mounted 5.0mm2 (.013mm thick) land areas. B.Measured on 8.3ms, and single half sine-wave or equivalent square wave ,duty cycle=4 pulses per minute maximum
APPLICATION NOTE: Since the actual voltage available from a given zener diode is temperature dependent, it is necessary to determinejunction temperature under any set of operating conditions in order to calculate its value. The following procedure is recommended: Lead Temperature, L , should be determined from: LA is the lead-to-ambient thermal resistance ( C/W) and Pd is the power dissipation. The value for L A will vary and depends on the device mounting method. A is generally 30-40 OC/W for the various clips and tie points in common use and for printed circuit board wiring. The temperature of the lead can also be measured using a thermocouple placed on the lead as close as possible to the tie point. The thermal mass connected to the tie point is normally large enough so that it will not significantly respond to heat surges generated in the diode as a result of pulsed operation once steady-state conditions are achieved. Using the measured value of TL, the junction temperature may be determined by: JL is the increase in junction temperature above the lead temperature and may be found from Figure 2 for a train of power pulses or from Figure 10 for dc power. T JL For worst-case design, using expected limits Z , limits P D and the extremes of may be estimated. Changes in voltage, Z , can then be found from: DV = qVZ DTJ the zener voltage temperature coefficient, is found from Figures 5 and 6. Under high power-pulse operation, the zener voltage will vary with time and may also be affected significantly by the zener resistance. For best regulation, keep current excursions as low as possible. Data of Figure 2 should not be used to compute surge capa-bility. Surge limitations are given in Figure 3. They are lower than would be expected by considering only junction temperature, as current crowding effects cause temperatures to be extremely high in small spots resulting in device degradation should the limits of Figure 3 be exceeded.