Stk411-210e Circuit Diagram

1. Key Features of STK411-210E

• Dual channel (stereo)
• Output Power: ~15W to 25W per channel into 4Ω or 8Ω (depending on supply voltage)
• Supply Voltage: Typically ±18V to ±28V
• Built-in thermal shutdown & overcurrent protection
• Low distortion

4. Schematic Reference (Text-based)

Here is a more formal schematic description (single channel shown; duplicate for stereo):

              +Vcc ──┬────────────┐
                   100µF          │
                    │            (7)
   INPUT ──┬────2.2µF───(2)      STK411-210E
           │                      │
          22kΩ ──┬────────────────(6)─── TO SPEAKER
           │     │                 │
          GND    │                 │
               1kΩ                (3)─── GND
                │                 
               GND                 
         (Feedback network)

Gain formula:
Av = 1 + (R_feedback / R_input) stk411-210e circuit diagram

Part 1: Key Specifications and Features

Before diving into the circuit diagram, let’s establish what this IC is capable of. Understanding the electrical limits is crucial for designing or repairing a circuit around this chip. Dual channel (stereo) Output Power: ~15W to 25W

| Parameter | Rating | | :--- | :--- | | Output Power (Typical) | 70W + 70W (Stereo) at 6Ω, 1kHz, 10% THD | | Output Power (Max) | 80W + 80W | | Recommended Supply Voltage (Vcc) | ±45V to ±55V (Symmetrical) | | Maximum Supply Voltage | ±65V | | Quiescent Current | 80 mA (Typical) | | Load Impedance | 6Ω to 16Ω | | Total Harmonic Distortion (THD) | 0.08% (at 1kHz, 50W) | | Input Impedance | 55 kΩ (Typical) | | Package | SIP-22 (Single Inline Package with 22 pins) | Transformer: 2x15V AC secondary (30V CT)

Key Feature: The STK411-210E employs a self-biasing, quasi-complementary output stage. It includes built-in over-voltage, over-temperature, and over-current protection circuits, making it relatively rugged for a hybrid IC.

4. Power Supply Design

The STK411-210E requires a split supply (±Vcc). A recommended supply:

• Transformer: 2x15V AC secondary (30V CT), 50VA minimum.
• Rectification: Full-wave bridge (4x 3A diodes).
• Filter caps: 4700µF to 6800µF per rail (35V rating).
• Decoupling: 100nF ceramic + 100µF electrolytic near IC pins 6 & 7.

Power calculation:
For ±21V into 8Ω: Max output swing ≈ ±19V (losses). Pmax = (19²)/(2×8) ≈ 22W peak, but thermally limited to 15W continuous per channel.