Is a class AB stereo audio power amplifier designed for quality hi-fi applications using a TDA2009A module. It is easy to construct and has a minimum of external components. The module has output current protection and thermal protection. This is the data book circuit which gives an excellent sound. The supply voltage required for this kit is 8 - 24V DC at 1 to 2 Amps. Maximum output power will only be obtained with a power supply of at least 20V and greater than 1.5 A, and using 4 ohm speakers. The power supply should be well filtered to reduce mains hum, the on board capacitors alone are not adequate for this purpose but are necessary to ensure stability. Extra filtering is unnecessary if operating from a battery.
Operation.
The circuit is very straight forward. Most of the circuitry is contained within the amplifier module. C1 & C2 are input coupling capacitors and block DC, as do C10 & C11 which are the output coupling capacitors, and C6 & C7 which block DC from the feed back loop. R1/R2 (and R3/R4) set the level of feed back. The gain is equal to 1 +(R1/R2) = 68 or 37 dB. C8/R5 (and C9/R6) provide a high frequency load for stability where loudspeaker inductive reactance may become excessive. C4 and C5 provide power supply decoupling or filtering. The absolute maximum supply voltage for this Kit is 28V. Check the power supply voltage and polarity before connecting to the board. We found no trouble in getting this kit to work. If yours does not work, first check all external wiring, make sure there are no shorts, then check all the component positions and orientation. Also check all solder joints and make sure there are no solder bridges.
Specifications :
D.C. Input : 8 – 24V at 1 – 2 A
Power output : > 10W RMS /channel, 4 ohm load, 24V DC supply.
> 6W RMS /channel 8 ohm load 24V DC supply.
> 4W RMS /channel, 4 ohm load 12V DC supply.
S/N ratio : > 75 dBA re. 10W output.
Frequency response : ~ 10 Hz to 50 kHz –3 dB
Gain : ~ 36 dB Input level : ~ 100 mV for full output
Circuit Diagram
Operation.
The circuit is very straight forward. Most of the circuitry is contained within the amplifier module. C1 & C2 are input coupling capacitors and block DC, as do C10 & C11 which are the output coupling capacitors, and C6 & C7 which block DC from the feed back loop. R1/R2 (and R3/R4) set the level of feed back. The gain is equal to 1 +(R1/R2) = 68 or 37 dB. C8/R5 (and C9/R6) provide a high frequency load for stability where loudspeaker inductive reactance may become excessive. C4 and C5 provide power supply decoupling or filtering. The absolute maximum supply voltage for this Kit is 28V. Check the power supply voltage and polarity before connecting to the board. We found no trouble in getting this kit to work. If yours does not work, first check all external wiring, make sure there are no shorts, then check all the component positions and orientation. Also check all solder joints and make sure there are no solder bridges.
Specifications :
D.C. Input : 8 – 24V at 1 – 2 A
Power output : > 10W RMS /channel, 4 ohm load, 24V DC supply.
> 6W RMS /channel 8 ohm load 24V DC supply.
> 4W RMS /channel, 4 ohm load 12V DC supply.
S/N ratio : > 75 dBA re. 10W output.
Frequency response : ~ 10 Hz to 50 kHz –3 dB
Gain : ~ 36 dB Input level : ~ 100 mV for full output
Circuit Diagram
Comments