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TDA2005-Based 4W-8W Stereo Power Amplifier
The circuit has been constructed to design a stereo power amplifier with the use of a single integrated circuit TDA2005 with 4W to 8W power output.Power Amplifier – a type of amplifier built and designed for the purpose of delivering and supplying sufficient and maximum high output power to directly drive loudspeakers or loads, within a given percent of distortion TDA2005 – a class B dual audio power amplifier in multiwatt package specifically designed for car radio applications and 20W bridge power booster stereo amplifiers due to its high current capability, high reliability, output AC & DC short circuit to ground, high output power, flexible for being bridge or stereo booster amplifier with or without bootstrap and with programmable gain and bandwidth, very low number of external components, very inductive load, load dump voltage surge, and very simple mounting system with no electrical isolation between the heatsink and the package
The general purpose of an amplifier is to take a signal from a source and uses a power amplifier that makes it suitable to drive a loudspeaker where the only thing that matters is the strength of the signal that differentiates the input signal and the output signal. In a class AB amplifier, as used in this circuit, the crossover distortion is virtually eliminated by having a small amount of bias current that is constantly flowing through the output transistors.
The operation of this power amplifier is handled by the TDA2005 IC module that is constructed easily with the use of minimal components. Some of the features that will best describe this circuit is the capability for thermal protection and output current protection while producing a good quality of audio. The voltage supply would only require the range of 9 V to 18 V at 1 A to 2 A. Given these ranges, the maximum output power that will only be taken from a power supply will be at least 15 Vdc at 2 A with a 2 Ohms speaker or a 2 X 4 Ohms speaker that is connected in parallel. In spite of obtaining 15 Vdc only, an estimated 4W per channel can be provided with 1 A supply into 4 Ohms loads.
The DC voltages are being blocked by capacitors C4 & C5 as they function as input coupling while C9-13 function as output coupling capacitors. The capacitors C8-12 are responsible for blocking the DC from the feedback loop to the differential inputs while the level of feedback is being set by R2-3 and R4-5. the stability of high frequency load is provided by C9/R6 and C13/R7 since the inductive reactance of the loudspeaker may become excessive.
The decoupling of power or filtering is provided by C1-2 while the gain is approximately 31 dB without any input attenuation, based from the values of the components. The gain may still be increased by reducing the feedback resistors R3 & R5. while having a maximum supply voltage of 18 V, the polarity should still be checked before the connection.
The power amplifier circuit made from TDA2005 is widely used in quality hi-fi applications by providing sufficient energy for amplification of signals from the AC wall socket. They are widely used in audio systems to drive loudspeakers because the last stage amplifier would require power efficiency attention. This particular 4W power amplifier is commonly used in WCDMA base stations in the pre-drive and driver stage and the output stage in repeaters.