MAX9728A/MAX9728B 19-3963 Rev 1 7/09 60mW, DirectDrive, Stereo Headphone Amplifiers with Shutdown General Description Features The MAX9728A/MAX9728B stereo headphone ampli- No Bulky DC-Blocking Capacitors Required fiers are designed for display and notebook applica- Low-Power Shutdown Mode, < 0.1A tions or portable equipment where board space is at a Adjustable Gain (MAX9728A) or Fixed -1.5V/V premium. These devices use a unique DirectDrive Gain (MAX9728B) architecture to produce a ground-referenced output from a single supply, eliminating the need for large DC- Low 0.02% THD+N blocking capacitors, saving cost, board space, and High PSRR (80dB at 1kHz) Eliminates LDO component height. The MAX9728A offers an externally adjustable gain, while the MAX9728B has an internally Integrated Click-and-Pop Suppression preset gain of -1.5V/V. The MAX9728A/MAX9728B 4.5V to 5.5V Single-Supply Operation deliver up to 60mW per channel into a 32 load and Low Quiescent Current (3.5mA) have low 0.02% THD+N. An 80dB at 1kHz power-sup- ply rejection ratio (PSRR) allows these devices to oper- Available in Space-Saving Packages ate from noisy digital supplies without an additional 12-Pin Thin QFN (3mm x 3mm x 0.8mm) linear regulator. Comprehensive click-and-pop circuitry 14-Pin TSSOP (5mm x 4.4mm x 1.1mm) suppresses audible clicks and pops on startup and shutdown. The MAX9728A/MAX9728B operate from a single 4.5V Ordering Information to 5.5V supply, consume only 3.5mA of supply current, feature short-circuit and thermal-overload protection, PART GAIN (V/V) PIN-PACKAGE TOP MARK and are specified over the extended -40C to +85C MAX9728AETC+ Adj. 12 TQFN-EP* ABC temperature range. The devices are available in tiny 12- pin Thin QFN (3mm x 3mm x 0.8mm) and 14-pin MAX9728AEUD+ Adj. 14 TSSOP TSSOP packages (5mm x 4.4mm x 1.1mm). MAX9728BETC+ -1.5 12 TQFN-EP* ABD MAX9728BEUD+ -1.5 14 TSSOP Applications Note: All devices specified over the -40C to +85C operating Notebook PCs CRT TVs range. +Denotes lead(Pb)-free/RoHS-compliant package. DVD Players Multimedia Monitors *EP = Exposed pad. LCD/PDP Displays DirectDrive is a registered trademark of Maxim Integrated Pin Configurations appear at end of data sheet. Product, Inc. Block Diagrams MAX9728B MAX9728A 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 Amplifiers with Shutdown ABSOLUTE MAXIMUM RATINGS V to PGND............................................................-0.3V to +6V OUT Short Circuit to SGND ......................................Continuous DD PV to SV .........................................................-0.3V to +0.3V Short Circuit between OUTL and OUTR ....................Continuous SS SS PGND to SGND .....................................................-0.3V to +0.3V Continuous Input Current into PV ..................................260mA SS C1P to PGND..............................................-0.3V to (V + 0.3V) Continuous Input Current (any other pin).........................20mA DD C1N to PGND............................................(PV - 0.3V) to +0.3V Continuous Power Dissipation (T = +70C) SS A PV and SV to PGND..........................................-6V to +0.3V 12-Pin TQFN (derate 14.7mW/C above +70C) .........1177mW SS SS IN to SGND (MAX9728A)..........................-0.3V to (V + 0.3V) 14-Pin TSSOP (derate 9.1mW/C above +70C) ...........727mW DD IN to SGND (MAX9728B).............(SV - 0.3V) to (V + 0.3V) Operating Temperature Range ...........................-40C to +85C SS DD OUT to SV (Note 1) ....-0.3V to Min (V - SV + 0.3V, +9V) Storage Temperature Range .............................-65C to +150C SS DD SS OUT to V (Note 2) ......+0.3V to Max (SV - V - 0.3V, -9V) Junction Temperature......................................................+150C DD SS DD SHDN to GND.........................................................-0.3V to +6V Lead Temperature (soldering, 10s) .................................+300C 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 MAX9728A gain = -1.5V/V DD L (R = 20k, R = 30k) for MAX9728B 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 4.5 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 MAX9728B, measured at IN 15 19 25 k IN Output Offset Voltage V 1.5 10 mV OS V = 4.5V to 5.5V 86 DD Power-Supply Rejection Ratio PSRR f = 1kHz, 100mV 80 dB P-P f = 20kHz, 100mV 65 P-P R = 32, THD+N = 1% 30 63 L Output Power P mW OUT R = 16, THD+N = 1% 42 L Voltage Gain A MAX9728B (Note 4) -1.52 -1.5 -1.48 V/V V Channel-to-Channel Gain MAX9728B 0.15 % Tracking 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 R = 16, P = 35mW, f = 1kHz 0.04 L OUT IN 2 MAX9728A/MAX9728B