5 Watt Surmetic 40  Zener  Voltage  Regulators 1N53 Series This is  a complete series of 5 Watt Zener diodes with tight limits and better operating characteristics that reflect the superior capabilities of silicon?oxide  passivated  junctions.  All  this  in an  axial  lead, transfer?molded plastic package that offers protection in all common environmental  conditions. Features • Zener Voltage Range ?  3.3 V to 200 V • ESD Rating of Class 3 (>16 kV) per Human Body Model • Surge Rating of up to 180 W @ 8.3 ms • Maximum Limits Guaranteed on up to Six Electrical Parameters • Pb?Free Packages are Available* Mechanical Characteristics CASE: Void free, transfer?molded, thermosetting plastic FINISH: All external surfaces are corrosion resistant and leads are readily solderable MAXIMUM LEAD TEMPERATURE FOR SOLDERING PURPOSES: 260°C, 1/16 in. from the case for 10 seconds POLARITY: Cathode indicated by polarity band MOUNTING POSITION: Any MAXIMUM RATINGS RatingSymbol Value Max. Steady State Power Dissipation @ TL  = 25°C, Lead Length = 3/8 in Derate above 25°C Junction?to?Lead Thermal Resistance PD Unit 5 40 JL Operating and Storage Temperature Range TJ, Tstg 25 ?65 to +200 (Note 1) W mW/°C °C/W °C Stresses exceeding those listed in the Maximum Ratings table may damage the device.  If any of these limits are exceeded, device functionality should not be assumed,  damage may occur and reliability may be affected. 1. Max operating temperature for DC conditions is 150°C, but not to exceed 200°C for pulsed conditions with low duty cycle or non?repetitive.