PAM8403 class-D amp
PAM8403 stereo class-D amplifier board · 2.5–5.5 V · 2 × 3 W into 4 Ω · gain 24 dB (× 16, bridge-tied) · filterless: the speaker coil averages the 250 kHz PWM · inputs AC-coupled · never ground L− or R−
Try it on the benchThe lab drops it on an empty bench and opens its datasheet card.
Typical part: Diodes Inc. PAM8403 module
Pins
- 5V
- GND
- L in
- R in
- L+
- L−
- R+
- R−
Ratings and limits
| Supply | 2.5–5.5 V |
|---|---|
| Power | 3 W per channel into 4 Ω at 5 V |
| Gain | 24 dB |
| Efficiency | ≈ 85–90 % |
How to use it
Each speaker goes between its + and − outputs (bridge-tied): never connect a − output to ground or to the other channel. Feed it line level from a DAC, phone or ESP32 through a volume pot.