125W Class D Audio Power Amplifier

The IC combination of the LM4651 driver and the LM4652
power MOSFET provides a high efficiency, Class D subwoofer
amplifier solution.
- Output Power, 1% THD 125W
- Load Impedance 4Ω
- Input Signal level 3V RMS (max)
- Input Signal Bandwidth 10Hz − 150Hz
- Ambient Temperature 50°C (max)
- Supply voltage +- 20V

LM4651
The LM4651 is a fully integrated conventional pulse width
modulator driver IC. The IC contains short circuit, under
voltage, over modulation, and thermal shut down protection
circuitry. The LM4651also contains a standby function which
shuts down the pulse width modulation minimizing supply
current. The LM4652 is a fully integrated H-bridge power
MOSFET IC in a TO-220 power package. The LM4652 has a
temperature sensor built in to alert the LM4651 when the die
temperature of the LM4652 exceeds the threshold. Together,
these two IC’s form a simple, compact high power audio
amplifier solution complete with protection normally seen
only in Class AB amplifiers. Few external components and
minimal traces between the IC’s keep the PCB area small
and aids in EMI control.

Features
- Conventional pulse width modulation.
- Externally controllable switching frequency.
- 50kHz to 200kHz switching frequency range.
- Integrated error amp and feedback amp.
- Turn−on soft start and under voltage lockout.
- Over modulation protection (soft clipping).
- Externally controllable output current limiting and
thermal shutdown protection.
- Self checking protection diagnostic.

LM4651 Datasheet Pdf