MAX9759 19-3691 Rev 1 10/05 3.2W, High-Efficiency, Low-EMI, Filterless, Class D Audio Amplifier General Description Features The MAX9759 mono Class D, audio power amplifier 3.2W into 4 Load (THD+N = 10%) provides Class AB amplifier audio performance with the Filterless Amplifier Passes FCC Radiated benefits of Class D efficiency, eliminating the need for a Emissions Standards with 7.6cm of Cable heatsink and extending battery life. The MAX9759 deliv- ers up to 3.2W of continuous power into a 4 load while 92% Efficiency offering greater than 90% efficiency. Maxims next-gen- High PSRR (81dB at 1kHz) eration, low-EMI modulation scheme allows the amplifi- er to operate without an external LC filter while still Low 0.02% THD+N meeting FCC EMI-radiated emission levels. External Clock Synchronization for Multiple, The MAX9759 offers two modulation schemes: a fixed- Cascaded Maxim Class D Amplifiers frequency modulation (FFM) mode and a spread-spec- trum modulation (SSM) mode. The SSM mode flattens 3.0V to 5.5V Single-Supply Operation the wideband spectral components, reducing EMI-radi- Pin-Selectable Gain (6dB, 12dB, 18dB, 24dB) ated emissions due to the modulation frequency. Furthermore, the MAX9759 oscillator can be synchro- Integrated Click-and-Pop Suppression nized to an external clock through the SYNC input, Low Quiescent Current (8.4mA) allowing the switching frequency to range from 1000kHz to 1600kHz. The SYNC input and SYNC OUT Low-Power Shutdown Mode (10A) output of the MAX9759 allow multiple Maxim Class D Mute Function amplifiers to be cascaded and frequency locked, mini- mizing interference due to clock intermodulation. The Short-Circuit and Thermal-Overload Protection MAX9759 utilizes fully differential input amplifiers, a full- Available in Thermally Efficient Package bridged output, comprehensive click-and-pop suppres- 16-Pin TQFN (4mm x 4mm x 0.8mm) sion, and features four selectable gain settings (6dB, 12dB, 18dB, 24dB). The MAX9759 features high 81dB PSRR, low 0.02% Ordering Information THD+N, and SNR in excess of 90dB. Short-circuit and thermal-overload protection prevents damage to the PIN- PKG device during a fault condition. The MAX9759 operates PART TEMP RANGE PACKAGE CODE from a single 5V supply, consumes 8.4mA of supply MAX9759ETE+ -40C to +85C 16 TQFN-EP* T1644-4 current, and is available in a 16-pin thin QFN package (4mm x 4mm x 0.8mm). The MAX9759 is fully specified +Denotes lead-free package. over the extended -40C to +85C temperature range. *EP = Exposed paddle. Simplified Block Diagram Applications V DD Cell Phones/PDAs Notebook PCs DIFFERENTIAL MODULATOR MONO SPEAKER Portable DVD Players AUDIO INPUT AND H-BRIDGE OUTPUT Flat-Panel PC Monitors LCD TVs SYNC OSCILLATOR INPUT LCD Projectors GAIN G1 SYNC CONTROL G2 OUTPUT SHDN SHDN CONTROL MAX9759 MUTE MUTE CONTROL Pin Configurations appear at end of data sheet. Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com. EVALUATION KIT AVAILABLE3.2W, High-Efficiency, Low-EMI, Filterless, Class D Audio Amplifier ABSOLUTE MAXIMUM RATINGS V to GND..............................................................................6V Continuous Power Dissipation (T = +70C) DD A PV to PGND .........................................................................6V 16-Pin TQFN (derate 16.9mW/C above +70C) .....1349.1mW DD GND to PGND .......................................................-0.3V to +0.3V Junction Temperature......................................................+150C All Other Pins to GND.................................-0.3V to (V + 0.3V) Operating Temperature Range ...........................-40C to +85C DD Continuous Current Into/Out of PV /PGND/OUT+/OUT-....1.7A Storage Temperature Range .............................-65C to +150C DD Duration of OUT+ or OUT- Short Circuit to Lead Temperature (soldering, 10s) .................................+300C V /GND/PV /PGND............................................Continuous ESD Protection (+IBM).........................................................2kV DD DD Duration of Short Circuit Between OUT+ and OUT- ..Continuous Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (V = 5.0V) DD (V = PV = SHDN = MUTE = 5V, GND = PGND = 0V, SYNC = 0V (FFM). Gain = 12dB (G1 = 0, G2 = 1). Speaker load resistor DD DD (R ) connected between OUT+ and OUT-, unless otherwise noted, R = , T = T to T , unless otherwise noted. Typical val- L L A MIN MAX ues are at T = +25C.) (Notes 1, 2) A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS GENERAL Supply Voltage Range V Inferred from PSRR test 3.0 5.5 V DD Quiescent Current I No load 8.4 12 mA DD Mute Current I V = 0V 5.5 8 mA MUTE MUTE Shutdown Current I V = 0V 0.1 10 A DD(SHDN) SHDN Shutdown to Full Operation t 40 ms SON Mute to Full Operation t 40 ms MUTE Common-Mode Rejection Ratio CMRR f = 1kHz, input referred, V = 200mV 67 dB IN P-P Input DC Bias Voltage V 1.3 1.5 1.7 V CM Gain = +24dB 14 20 26 Gain = +18dB 25 36 47 Input Resistance R k IN Gain = +12dB 40 60 80 Gain = +6dB 60 90 120 G1 = 0, G2 = 0 +22 +24 +26 G1 = 1, G2 = 0 +16 +18 +20 Voltage Gain A dB V G1 = 0, G2 = 1 +10 +12 +14 G1 = 1, G2 = 1 +4 +6 +8 Output Offset Voltage V T = +25C 10 50 mV OS A V = 4.5V to 5.5V 62 90 DD f = 217Hz 79 RIPPLE Power-Supply Rejection Ratio PSRR dB (Note 3) 200mV ripple f = 1kHz 81 P-P RIPPLE f = 20kHz 70 RIPPLE 2 MAX9759