Description
High-Output 100W+100W Stereo Audio Power Amplifier Module
The STK4231II is a heavy-duty thick-film hybrid integrated circuit from Sanyo's trusted "Series II" line. Delivering a continuous 100 Watts per channel, this module was the preferred choice for flagship stereo receivers, high-power AV systems, and integrated amplifiers throughout the 1990s.
Engineered for split-power supply systems, the STK4231II provides a balanced analog sound with a Total Harmonic Distortion (THD) of 0.4%. It features an internal constant-current circuit to eliminate power-on "thump," protecting your speakers while offering the rugged thermal reliability Sanyo hybrid chips are known for.
Key Technical Features:
- Continuous Power Output: 100W + 100W (at 8Ω, 20Hz to 20kHz, THD = 0.4%).
- Configuration: 2-Channel Stereo in a 22-Pin SIP (Single In-line Package).
- Thermal Excellence: Optimized substrate designed for high heat dissipation (Thermal Resistance 1.1°C/W).
- Frequency Response: Full-range high-fidelity from 20Hz to 50kHz.
- Operating Voltage: Recommended supply of ±51V (Absolute Maximum ±75V).
- Pin Compatibility: Pin-compatible with the STK4201II series (60W to 100W) for easy cross-referencing and modular upgrades.
Installation & Technical Guide:
As a 200W total output module, the STK4231II generates significant thermal energy. It must be securely mounted to a large, high-mass heatsink using premium thermal silicone grease. Operating this module without a heatsink—even for a five-second diagnostic check—will cause immediate and permanent internal failure.
Technician's Note: Before installation, verify that the power supply rails are symmetrical and discharge all filter capacitors. Always check the output emitter resistors (typically 0.22Ω to 0.47Ω), as they are often damaged when the original module fails.