Transistor Can Packages TO-72 Case style, Metal Can
TO-72 Metal Can, 4-Terminal
The TO-72 package is a 4 pin device in a metal can. This is a through-hole device.
As with any package, any number of uses will be found for a TO-72 metal can, as in a photodiode with phototransistor, or a Dual-Gate FET. Of course the pin functions change depending on what circuit resides within the device.
Like any other metal case, a number of heat sinks are possible which will also fit a TO-18, or a TO-78 package. Check the thermal Resistance of the heat sink and use thermal grease if required.
The 2N4416A N-Channel FET uses the TO-72 package as;
Lead 1 = source, lead 2 = drain, lead 3 = gate, lead 4 = case.
The 2N2857 Low-Power NPN Transistor uses the TO-72 package as;
Lead 1 = emitter, lead 2 = base, lead 3 = collector, lead 4 = case (electrically connected).
PNP Switching Transistor 2N4261.
