The MAX9701 stereo Class D audio power amplifier provides Class AB amplifier audio performance with the benefits of Class D efficiency, eliminating the need for a heatsink while extending battery life. The MAX9701 delivers up to 1.3W per channel into an 8Ω load while offering 87% efficiency. Maxim's next-generation, low-EMI modulation scheme allows the amplifier to operate without an external LC filter while still meeting FCC EMI emission levels. The MAX9701 offers two modulation schemes: a fixed-frequency (FFM) mode, and a spread-spectrum (SSM) mode that reduces EMI-radiated emissions. The MAX9701 oscillator can be synchronized to an external clock through the SYNC input, allowing synchronization of multiple Maxim Class D amplifiers. The sync output (SYNC_OUT) can be used for a master-slave application where more channels are required. The MAX9701 features a fully differential architecture, a full bridge-tied load (BTL) output, and comprehensive click-and-pop suppression. The device features internally set gains of 0dB, 6dB, 12dB, and 18dB selected through two gain-select inputs, further reducing external component count. The MAX9701 features high 80dB PSRR, less than 0.1% THD+N, and SNR in excess of 88dB. Short-circuit and thermal-overload protection prevent the device from being damaged during a fault condition. The MAX9701 is available in 24-pin thin QFN-EP (4mm x 4mm x 0.8mm), and 20-bump UCSP™ (2mm x 2.5mm x 0.6mm) packages. The MAX9701 is a high-efficiency, low-EMI Class D amplifier designed specifically for mobile device applications, enabling low power consumption and high audio quality.
The MAX9701 stereo Class D audio power amplifier delivers up to 1.3 W per channel into an 8 Ω load while achieving 87 % efficiency. It uses a low‑EMI modulation scheme that eliminates the need for an external LC filter, extending battery life for portable devices.
The device is available in compact 24‑pin thin QFN‑EP and 20‑bump UCSP packages, supports fixed‑frequency and spread‑spectrum modes, and offers internally set gains of 0 dB, 6 dB, 12 dB, and 18 dB selectable via two gain‑select inputs. Protection features include short‑circuit and thermal‑overload shutdown.
| Maximum Output Power | 1.3 W per channel into 8 Ω |
|---|---|
| Efficiency | ≈ 87 % at 8 Ω load |
| THD+N | < 0.1 % |
| Power‑Supply Rejection Ratio (PSRR) | ≈ 80 dB |
| Signal‑to‑Noise Ratio (SNR) | > 88 dB |
| Package Options | 24‑pin thin QFN‑EP (4 mm × 4 mm × 0.8 mm) or 20‑bump UCSP (2 mm × 2.5 mm × 0.6 mm) |
It can deliver up to 1.3 W per channel into an 8 Ω load.
The amplifier reaches about 87 % efficiency when delivering 1 W into an 8 Ω load.