STK4221 general description:
The STK4221II IC from SANYO is a dual high power amplifier chip, preferably suited for compact high power audio applications, for example in cars and luxury transport vehicle audio systems. The chip provides a hassle free stereo output through a single package and a hand full of few external components, making the construction of this circuit rather easy and straightforward. However since the idea presented here does not include a CD or a memory card driver circuit, the input may be derived from readymade audio sources like an ipod, CD walkman, cellphone etc. The circuit discussed here is intended specifically for car audio applications and provides a simple alternative for
making a 100 watt car stereo amplifier circuit. The diagram may be understood with the following points: An RC network formed by R5, R6 and C3, C4 together helps to reduce and filter stray frequency interferences and is therefore included at the input of the amplifiers. Capacitors C5 and C6 are the coupling capacitors used for blocking DC. The values of these capacitors are chosen such that it does not introduce high reactance levels at low frequencies. This particularly helps to reduce the influence of the input interference noises over the signal source resistance. The value of these capacitors may also be optimized for reducing the “pop” noise when power is switched ON.
STK4221 features:
- Quiescent current ICCO VCC = ±54V 20 40 100 mA
- Output power POTHD = 0.4%, f = 20Hz to 20kHz 80 W
- Total harmonic distortion THD PO = 1.0W, f = 1kHz 0.3 %
- Frequency response fL, fH PO = 1.0W, dB 20 to 50k Hz
- Input impedance ri PO = 1.0W, f = 1kHz 55 kΩ
- Output noise voltage VNO VCC = ±54V, Rg = 10kΩ 1.2 mVrms
- Neutral voltage VN VCC = ±54V -70 0 +70 mV
- Muting voltage VM -2 -5 -10 V
STK4221 circuit diagram:
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| STK4221 Audio Amplifier 2x80w |
STK4221 pcb layout:
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| STK4221 Audio Amplifier 2x80w |
