BFY51 Transistor
From DT Online
Description
The BFY51 Collector is connected to the positive (+ve) supply via the load. NB If the load is inductive i.e. has coil windings such as a relay, solenoid or motor, then it is usual to connect a diode across it to prevent the Back EMF from damaging the transistor. (Cathode to supply). The input is connected to the Base via a limiting resistor (typically 1K). The Emitter is connected to the negative (-ve) supply (0V).
Features and Applications
Uses: As current amplifiers and electronic switches, for example, Motor Drive Amplifiers, Audio Amplifiers.
Data: Voltage between Collector and Emitter 6 - 30Volts max.
- Power handling capacity 800mWatts max.
- Current handling capacity 1 Amp max.
- Amplification (gain) greater than 50.
Note: Older Transistors such BFY51 may sometimes be difficult to obtain but 2N3053 is a good substitute (i.e. it is NPN, can operate with similar voltage and current and has the same TO-5 metal case and pin-out). BC548B is a another, lower power, equivalent with a TO-92 plastic case but many others exist and can be found in transistor equivalents tables).
