18w amp schematic using HA13118
18 Watt Audio Amplifier
Kit 105 is a class AB audio power amplifier using the Hitachi HA13118 module. It easy to construct and has a minimum of external components. The module has a high power output from a low voltage supply using the bridge tied method, and a high gain of 55dB. This will be especially useful in applications where the input signal is a low level, without requiring the use of a separate pre-amplifier, eg. a guitar practice amplifier.
Full current, and thermal protection is provided by the IC, making it extremely reliable.
D.C. Input : 8-18V, 1-2A
Power Output : 18W, 4 Ohm, 18V
>10W, 4Ohm, 18V
>5W, 8 Ohm, 18V
>6W, 4 Ohm, 12V
The supply voltage required for this kit is 8-18V DC, at least 1 to 2 Amps. Maximum output power will only be obtained with a power supply of 18V at greater than 2A, using a 4 ohm speaker. The power supply should be well filtered to reduce mains hum, a regulated supply will reduce noise even further. Extra filtering is unnecessary if operating from a battery supply.