MAX9708：20W/40W, Filterless, Spread-Spectrum, Mono/Stereo, Class D Amplifier

The MAX9708 mono/stereo, Class D audio power amplifier delivers up to 2 x 21W into an 8Ω stereo mode and 1 x 42W into a 4Ω load in mono mode while offering up to 87% efficiency. The MAX9708 provides Class AB amplifier performance with the benefits of Class D efficiency, eliminating the need for a bulky heatsink and conserving power. The MAX9708 operates from a single +10V to +18V supply, driving the load in a BTL configuration. The MAX9708 offers two modulation schemes: a fixed-frequency modulation (FFM) mode, and a spread-spectrum modulation (SSM) mode that reduces EMI-radiated emissions. The MAX9708 can be synchronized to an external clock from 600kHz to 1.2MHz. A synchronized output allows multiple units to be cascaded in the system. Features include fully differential inputs, comprehensive click-and-pop suppression, and four selectable-gain settings (22dB, 25dB, 29.5dB, and 36dB). A pin-programmable thermal flag provides seven different thermal warning thresholds. Short-circuit and thermal-overload protection prevent the device from being damaged during a fault condition. The MAX9708 is available in a 56-pin TQFN (8mm x 8mm x 0.8mm) package and is specified over the extended -40°C to +85°C temperature range.

Key Features

2 x 21W Output Power in Stereo Mode (8Ω, THD = 10%)
1 x 42W Output Power in Mono Mode (4Ω, THD = 10%)
High Efficiency: Up to 87%
Filterless Class D Amplifier
Unique Spread-Spectrum Mode
Programmable Gain (+22dB, +25dB, +29.5dB, +36dB)
High PSRR (90dB at 1kHz)
Differential Inputs Suppress Common-Mode Noise
Shutdown and Mute Control
Integrated Click-and-Pop Suppression
Low 0.1% THD+N
Current Limit and Thermal Protection
Programmable Thermal Flag
SYNC Input/Output
Available in Thermally Efficient, Space-Saving 56-Pin TQFN Package

MAX9708: Simplified Block Diagram

Applications/Uses

Automotive
LCD TVs
PC/HiFi Audio Solutions
PDP TVs

DataSheet

title	Download file
MAX9708 Data Sheet	MAX9708.pdf

Parametrics

Part Number	Class	Spkr. Amp. V_CC (V)	Spkr. Amp. V_CC (V)	Spkr. Amp. I_CC (mA)	P_OUT into 4Ω @ 1% THD+N (W)	P_OUT into 4Ω @ 10% THD+N (W)	P_OUT into 8Ω @ 1% THD+N (W)	P_OUT into 8Ω @ 10% THD+N (W)	Spkr. Amp. Half Pwr. THD+N (%)	SNR (dB)	PSRR (dB)	Package/Pins	Budgetary Price
Part Number	Class	min	max	typ	min	min	min	min	Spkr. Amp. Half Pwr. THD+N (%)	A- Weighted	min	Package/Pins	See Notes
MAX9708	D	10	18	20	32	42	16	21	0.15	95	90	TQFN/56	$2.98 @1k

Design kits & evaluation modules

MAX9708EVKIT

Quality and Environmental Data

MAX9708.pdf

Ordering Information

Part Number	Status	Package	Temp	RoHS
MAX9708ETN+D	Active	TQFN,;56 pin;65.6 mm²	-40°C to +85°C	Lead Free
MAX9708ETN+TD	Active	TQFN,;56 pin;65.6 mm²	-40°C to +85°C	Lead Free
MAX9708ETN/V+TD	No Longer Available	TQFN,;56 pin;65.6 mm²	-40°C to +85°C	Lead Free

MAX9708.pdf MAX9708