2N3762 Transistor Derating Guide

2N3762 Temperature-Power Derating Curve [2N3763, 2N3764, 2N3765]
PNP Silicon Switching Transistor. Package, TO-39 metal Can [TO-5, TO-46, U4].
PNP 2N3762 applications; Core driver.

Use the Graph to obtain maximum operational power based on junction temperature. Derating Curves for Transistors
The graph depicts the maximum allowable power dissipation at some ambient temperature [in still air]. Maximum operational power dissipation is achievable only at 25C. Above 25C the maximum package power dissipation, must be reduce to insure that the devices junction temperature remains constant. The higher the ambient temperature is increased the lower the allowable power dissipation, as depicted in the transistor curves.

An alternate derating method; Derate linearly at 5.71 mW/⁰C for TA > +25⁰C

Graph Notes:
1. Maximum theoretical derate design curve. This is the true inverse of the worst case thermal resistance value. All devices are capable of operating at < TJ specified on this curve. Any parallel line to this curve will intersect the appropriate power for the desired maximum TJ allowed.
2. Derate design curve constrained by the maximum junction temperature (TJ < 200^oC) and power rating specified.
3. Derate design curve chosen at TJ < 150^oC, where the maximum temperature of electrical test is performed.
4. Derate design curve chosen at TJ < 125^oC, and 110⁰C to show power rating where most users want to limit TJ in their application.

Refer to MIL-PRF-19500/396; Semiconductor Device Transistor, PNP, Silicon, Switching, Types 2N3762, 2N3762L, 2N3762U4, 2N3762UA, 2N3763, 2N3763L, 2N3763U4, 2N3763UA, 2N3764, and 2N3765, JAN related components, [TO-5, TO-39, TO-46 through-hole device, or U4/UA surface mount package]
Different transistors use different packages;
2N3762L and 2N3763L reside in a TO-5 package.
2N3762 and 2N3763 reside in a TO-39 package.
2N3764 and 2N3765 reside in a TO-46 package.

2N3762 Maximum Electrical Characteristics:
Collector Emitter Voltage = 40 volts dc
Power Dissipation 25⁰C = 1 Watt
Operating Temperature = -65 to +200⁰C
Note at 200⁰C, maximum operational wattage is 0 watts

Transistor Manufacturers, vendors. Heat Sink Manufacturers for small metal cans.

Lead Code: 1 is Emitter, lead 2 is Base, and lead 3 is Collector [Case Style is left].

Refer to MIL-PRF-19500; General Specification for Semiconductor Devices

How to Derate; Guideline for Derating Electronic Components

Technical Definitions:

Ambient Temperature. Ambient temperature is the air temperature measured below a semiconductor device, in an environment of substantially uniform temperature, cooled only by natural air convection, and not materially affected by reflective and radiant surfaces.

Thermal Compound Thermal grease will increases the thermal conductivity between the case and heat sink.

Thermal Conductivity The property of a material that indicates its ability to conduct heat.

Thermal Resistance. Thermal resistance is the temperature rise, per unit power dissipation, of a junction above the temperature of a stated external reference point under conditions of thermal equilibrium.