BD537 Bipolar Transistor NPN 80V 4A

The BD537 Bipolar Transistor NPN 80V 4A is an NPN power transistor for switching and amplifying larger currents than small-signal parts such as the BC547 or 2N2222 can handle. With a collector-emitter voltage rating of 80 V and a collector current of 4 A, it suits audio amplifier output stages, power supplies and drivers for motors, relays and lamps.

BD537 Bipolar Transistor NPN 80V 4A Specifications

• Type: NPN bipolar junction transistor (BJT)
• Collector-emitter voltage: 80 V
• Collector current: 4 A
• Terminals: 3 (base, collector, emitter)
• Use: power switching and linear amplification

BD537 Bipolar Transistor NPN 80V 4A Applications

• Audio power amplifier output and driver stages
• Linear voltage regulators and power supply pass stages
• Driving DC motors, solenoids, relays and lamps from a microcontroller
• Switching circuits and electronic loads
• Repair and replacement work in power electronics

What's in the Box

• 1 × BD537 NPN transistor

Tip: Always use a base resistor when driving it from a microcontroller pin, and add a flyback diode such as the 1N4007 across inductive loads like motors and relays. At higher currents mount it on a heatsink, and check the pinout in the datasheet before soldering.

Orders placed before 14:00 are ready for pickup the same day. Delivery across Lebanon usually takes 1–3 working days.