Amplifier circuit board with speaker protection

Electronics Help Care April 17, 2026 Uncategorized

This is the amplifier circuit board with speaker protection using transistors. here use 2sc5200 and 2sa1943. This is the transistor board only here needs an amplifier driver circuit board. It’s a mono amplifier circuit board. Here, use 6 transistors. 2sc5200 and 2sa1943. We can also use another transistor. PNP and NPN transistors. we can use 25-0-25 voltage to 70-0-70 voltage in this circuit.

1 Pair (2SC5200 + 2SA1943) transistoes can make

Using ±35V supply → about 80W – 100W RMS (8Ω). Using ±45V supply → about 120W – 150W RMS (8Ω). Using ±50V supply → up to 150W – 180W RMS (8Ω).

Basic Specification for 2sc5200

Transistor Type is NPN Power Transistor
Transistor Collector-Emitter Voltage (Vceo): 230V
Transistor Collector-Base Voltage (Vcbo): 230V
Transistor Emitter-Base Voltage (Vebo): 5V
Transistor Collector Current (Ic): 15A
The Power Dissipation (Pc): 150W
The transistor Gain (hFE): 55 – 160
Transition Frequency is (fT): ~30 MHz.

Basic Specification for 2sa1943

Transistor Type is PNP Power Transistor
Transistor Collector-Emitter Voltage (Vceo): 230V
Transistor Collector-Base Voltage (Vcbo): 230V
Transistor Emitter-Base Voltage (Vebo): 5V
Transistor Collector Current (Ic): 15A
The Power Dissipation (Pc): 150W
The transistor Gain (hFE): 55 – 160
Transition Frequency is (fT): ~30 MHz.

This is a Stereo amplifier circuit diagram using transistors 2SC5200 and 2SA1943. It’s a dual-channel audio amplifier circuit board. left and right channels. Each channel can make 150 watts of output. We can use a minimum 25-0-25 voltage to 50-0-50 voltage. Here needs AC voltage. We can also use other transistors. any type of PNP and NPN transistors.