100 watt mosfet amplifier PCB only
Price Rs 129.00 Each
Assembled & Tested Amplifier Board
Price Rs 549.00 Each
100 watt mosfet amplifier pcb
In making this simple but exceptionally well performing amplifier, we took inspiration from the original HITACHI lateral mosfet circuit from 1970's which was used in many famous sound systems and guitar amplifiers.
you can find the the original circuit HERE and an old British version HERE.
Very few components required, just one capacitor in signal path.
Experience uncolored sound of this simple circuit, you will love it.
New version of PCB having Space for Fitting Heatsinks easily.
With this amp you can make -
CLICK HERE to download 100 watt mosfet amplifier circuit diagram
Input stage works as a transconductance amplifier (voltage in - current out).
This stage consist of Long Tailed Pair (LTP) made of Q1 & Q2 working as differential amplifier.
Input signal received at the base of Q1 is amplified and sent to VAS from collector.
Negative feedback (NFB) received at the base of Q2 from output determines overall gain and balance of the amplifier. Current is supplied to the LTP by resistor R4.
In simple words input signal is amplified by the input pair Q1 & Q2 and sent to VAS for further amplification.
Voltage Amplification Stage (VAS)
As the name suggests, all the voltage gain of the amplifier is achieved in VA Stage.
Signal received from input stage at the base of Q5 is Voltage amplified and sent to the gate of mosfet Q7.
In simple words signal received from input stage is amplified by Q3 & sent to output stage.
Output Stage ( OPS )
This circuit has Class B output stage, so each half of the signal is amplified by each N-channel and P-channel mosfet.
Zobel Network - made of R15 & C6, provides protection against high frequency oscillations.
In simple words signal received from VAS is given to the output mosfets. Output mosfet conduct high current to drive the speakers load.