MAX9724A/MAX9724B 19-3597 Rev 6 3/09 60mW, DirectDrive, Stereo Headphone Amplifier with Low RF Susceptibility and Shutdown General Description Features The MAX9724A/MAX9724B stereo headphone ampli- Improved RF Noise Rejection (Up to 67dB Over fiers are designed for portable equipment where board Typical Amplifiers) space is at a premium. These devices use a unique No Bulky DC-Blocking Capacitors Required DirectDrive architecture to produce a ground-refer- Low-Power Shutdown Mode, < 0.1A enced output from a single supply, eliminating the need Adjustable Gain (MAX9724A) or Fixed -1.5V/V for large DC-blocking capacitors, saving cost, board Gain (MAX9724B) space, and component height. The MAX9724 sup- Low 0.02% THD+N presses RF radiation received by input and supply traces acting as antennas and prevents the amplifier High PSRR (80dB at 1kHz) Eliminates LDO from demodulating the coupled noise. The MAX9724A Integrated Click-and-Pop Suppression offers an externally adjustable gain while the 2.7V to 5.5V Single-Supply Operation MAX9724B has an internally preset gain of -1.5V/V. The Low Quiescent Current (3.5mA) MAX9724A/MAX9724B deliver up to 60mW per channel into a 32 load and have low 0.02% THD+N. An 80dB Available in Space-Saving Packages at 1kHz power-supply rejection ratio (PSRR) allows 12-Bump UCSP (1.5mm x 2mm) these devices to operate from noisy digital supplies 12-Pin Thin QFN (3mm x 3mm x 0.8mm) without an additional linear regulator. Comprehensive Ordering Information click-and-pop circuitry suppresses audible clicks and pops on startup and shutdown. GAIN PIN- TOP PART (V/V) PACKAGE MARK The MAX9724A/MAX9724B operate from a single 2.7V to 5.5V supply, consume only 3.5mA of supply current, MAX9724AEBC+TG45 Adj. 12 UCSP +ADH feature short-circuit and thermal-overload protection, MAX9724AETC+ Adj. 12 TQFN-EP* +AAT and are specified over the extended -40C to +85C MAX9724BEBC+TG45 -1.5 12 UCSP +ADI temperature range. The devices are available in tiny 12- bump UCSP (1.5mm x 2mm) and 12-pin thin QFN MAX9724BETC+ -1.5 12 TQFN-EP* +AAU (3mm x 3mm x 0.8mm) packages. Note: All devices specified over the -40C to +85C operating range. Applications +Denotes lead(Pb)-free/RoHS-compliant package. DVD Players Cellular Phones T = Tape and reel. *EP = Exposed paddle. Smart Phones MP3 Players Pin Configurations appear at end of data sheet. Notebook PCs PDAs Handheld Gaming Consoles UCSP is a trademark of Maxim Integrated Products, Inc. DirectDrive is a registered trademark of Maxim Integrated Products, Inc. Block Diagrams MAX9724B MAX9724A DirectDrive OUTPUTS DirectDrive OUTPUTS LEFT ELIMINATE DC-BLOCKING LEFT ELIMINATE DC-BLOCKING AUDIO CAPACITORS AUDIO CAPACITORS INPUT INPUT SHDN SHDN RIGHT RIGHT AUDIO FIXED GAIN ELIMINATES AUDIO INPUT EXTERNAL RESISTOR INPUT NETWORK Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com. EVALUATION KIT AVAILABLE60mW, DirectDrive, Stereo Headphone Amplifier with Low RF Susceptibility and Shutdown ABSOLUTE MAXIMUM RATINGS V to GND..............................................................-0.3V to +6V Continuous Input Current into PV ..................................260mA DD SS PV to SV .........................................................-0.3V to +0.3V Continuous Input Current (any other pin).........................20mA SS SS PGND to SGND .....................................................-0.3V to +0.3V Continuous Power Dissipation (T = +70C, Multilayer board) A C1P to PGND..............................................-0.3V to (V + 0.3V) 12-Bump UCSP (derate 6.5mW/C above +70C) ........519mW DD C1N to PGND............................................(PV - 0.3V) to +0.3V ................................................................................154 C/W SS JA PV and SV to PGND..........................................-6V to +0.3V 12-Pin TQFN (derate 16.7mW/C above +70C) .........1333mW SS SS IN to SGND (MAX9724A)..........................-0.3V to (V + 0.3V) ..................................................................................60C/W DD JA IN to SGND (MAX9724B).............(SV - 0.3V) to (V + 0.3V) ..................................................................................11C/W SS DD JC OUT to SV (Note 1) ....-0.3V to Min (V - SV + 0.3V, +9V) Operating Temperature Range ...........................-40C to +85C SS DD SS OUT to V (Note 2) ......+0.3V to Max (SV - V - 0.3V, -9V) Storage Temperature Range .............................-65C to +150C DD SS DD SHDN to GND.........................................................-0.3V to +6V Junction Temperature......................................................+150C OUT Short Circuit to GND ........................................Continuous Lead Temperature (soldering, 10s) .................................+300C Short Circuit between OUTL and OUTR ....................Continuous Bump Temperature (soldering) Reflow............................+235C Note 1: OUTR and OUTL should be limited to no more than 9V above SV , or above V + 0.3V, whichever limits first. SS DD Note 2: OUTR and OUTL should be limited to no more than 9V below V , or below SV - 0.3V, whichever limits first. DD SS 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 = 5V, PGND = SGND, SHDN = 5V, C1 = C2 = 1F, R = , resistive load reference to ground for MAX9724A gain = -1.5V/V DD L (R = 20k, R = 30k) for MAX9724B gain = -1.5V/V (internally set), T = -40C to +85C, unless otherwise noted. Typical values IN F A are at T = +25C, unless otherwise noted.) (Note 3) A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS GENERAL Supply Voltage Range V Guaranteed by PSRR test 2.7 5.5 V DD Quiescent Current I 3.5 5.5 mA CC Shutdown Current I SHDN = SGND = PGND 0.1 1 A SHDN Shutdown to Full Operation t 180 s SON Input Impedance R MAX9724B, measured at IN 12 19 28 k IN Output Offset Voltage V (Note 4) 1.5 10 mV OS V = 2.7V to 5.5V, T = +25C 69 86 DD A Power-Supply Rejection Ratio PSRR f = 1kHz, 100mV (Note 4) 80 dB P-P f = 20kHz, 100mV (Note 4) 65 P-P R = 32, THD+N = 1% 30 63 L Output Power (TQFN) P mW OUT R = 16, THD+N = 1% 42 L R = 32, THD+N = 1% 25 45 L Output Power (UCSP) P mW OUT R = 16, THD+N = 1% 35 L Voltage Gain A MAX9724B (Note 5) -1.52 -1.5 -1.48 V/V V Channel-to-Channel Gain Tracking MAX9724B 0.15 % R = 1k, V = 2V , f = 1kHz 0.003 L OUT RMS IN Total Harmonic Distortion Plus THD+N % R = 32, P = 50mW, f = 1kHz 0.02 L OUT IN Noise (TQFN) (Note 6) R = 16, P = 35mW, f = 1kHz 0.04 L OUT IN R = 1k, V = 2V , f = 1kHz 0.003 L OUT RMS IN Total Harmonic Distortion Plus THD+N R = 32, P = 45mW, f = 1kHz 0.03 % L OUT IN Noise (UCSP) (Note 6) R = 16, P = 32mW, f = 1kHz 0.05 L OUT IN BW = 22Hz to 22kHz 102 R = 1k, L V = 2V OUT RMS A-weighted 105 Signal-to-Noise Ratio SNR dB BW = 22Hz to 22kHz 98 R = 32, L P = 50mW OUT A-weighted 101 2 MAX9724A/MAX9724B