Analog Devices Inc. MAX98366 15V Plug-and-Play Class-D Amplifiers
Analog Devices Inc. MAX98366 15V Plug-and-Play Class-D Amplifiers are user-friendly, cost-effective digital input amplifiers that deliver Class-AB audio quality with the efficiency of Class-D technology. Designed for simplicity, the MAX98366 amplifiers automatically detect various PCM and time division multiplexed (TDM) clocking schemes, eliminating the need for I2C configuration. Just apply power, LRCLK, BCLK, and digital audio to start playback. An innovative pinout enables the use of a wafer-level package (WLP) without requiring costly in-pad vias, helping reduce overall system cost. With a wide operating voltage range from 3V to 15V, these amplifiers can deliver up to 15W into an 8Ω load.
The digital audio interface is highly versatile, supporting I2S, left-justified, and 8-channel TDM formats. The interface accommodates sample rates from 8kHz to 192kHz. For rates above 48kHz, it automatically enables a passband of 38.8kHz and higher, making the amplifiers suitable for ultrasound applications. Supported data word lengths include 16-, 24-, and 32-bit in I2S and left-justified modes, and 16- or 32-bit in TDM mode.
Input thresholds are optimized for compatibility with 1.2V and 1.8V logic, while tolerating voltages up to 5.5V. The MAX98366A/B variants feature fast 1ms turn-on times, while the MAX98366C/D models offer 13ms volume ramping during power transitions for smoother audio performance.
By eliminating the need for an external MCLK signal, the Analog Devices MAX98366 amplifiers reduce EMI and simplify board layout. MAX98366 also boasts high jitter tolerance (12ns typical) on BCLK and LRCLK for reliable operation. Integrated features like active emissions limiting, edge-rate control, and overshoot suppression further minimize EMI.
Thanks to filterless spread-spectrum modulation, the MAX98366 removes the need for traditional output filters, reducing component count and simplifying design. These amplifiers are rated for operation across a wide -40°C to +85°C temperature range, suitable for a variety of demanding applications.
Features
- Simple plug-and-play design, no I2C register programming required
- Wide 3V to 15V amplifier supply range
- Wideband filters for fS = 88.2kHz and higher
- 15W output power into 8Ω at PVDD = 15V
- 19.3W output power into 6Ω at PVDD = 15V
- 30mW quiescent power
- 1.1ms turn-on time (for MAX98366A and MAX98366B)
- 92.7% efficiency (7.0W into RL = 8Ω, PVDD = 12V)
- 20μVRMS idle output noise at fS ≤ 48kHz, 37μVRMS at fS > 50kHz
- 112dB dynamic range at fS ≤ 48kHz, 107dB at fS > 50kHz
- -85dB THD+N at 1kHz
- No MCLK required
- 8kHz to 192kHz sample rate range
- Supports left, right, or (left/2 + right/2) output in I2S and left-justified modes
- Sophisticated edge rate control enables filterless Class-D outputs
- Low 0.5μA shutdown current
- Class-D switching frequency trimmed to 6% for improved EMI planning
- Extensive click-and-pop reduction circuitry
- Robust short-circuit and thermal protection
- Space-saving 12-bump WLP package, 1.21mm x 1.78mm, 0.4mm pitch
- -40°C to +85°C operating temperature range
Applications
- Smart speakers
- Wireless speakers
- Smart Internet of Things (IoT) and smart home devices
- Gaming devices (audio and haptics)
- Laptops and tablets
- Cameras
Simplified Block Diagram
Development Tools
Analog Devices Inc. MAX98366 Evaluation Systems
Designed to evaluate the MAX98366A/B/C/D mono Class-D audio amplifiers with ultrasound support.