MAX4409 19-2842 Rev 3 6/09 80mW, DirectDrive, Stereo Headphone Amplifier with Common-Mode Sense General Description Features The MAX4409 stereo headphone amplifier combines No Bulky DC-Blocking Capacitors Required Maxims DirectDrive architecture and a common- Ground-Referenced Outputs Eliminate DC-Bias mode sense input, which allows the amplifier to reject Voltages on Headphone Ground Pin common-mode noise. Conventional headphone ampli- Common-Mode Voltage Sensing Eliminates fiers require a bulky DC-blocking capacitor between Ground-Loop Noise the headphone and the amplifier. DirectDrive produces 96dB CMRR a ground-referenced output from a single supply, elimi- nating the need for large DC-blocking capacitors, No Degradation of Low-Frequency Response Due which saves cost, board space, and component height. to Output Capacitors The common-mode voltage sensing corrects for any 80mW per Channel into 16 difference between SGND of the amplifier and the Low 0.002% THD+N headphone return. This feature minimizes ground-loop High 86dB PSRR noise when the HP socket is used as a line out connec- Integrated Click-and-Pop Suppression tion to other grounded equipment, for example, a PC connected to a home hi-fi system. 1.8V to 3.6V Single-Supply Operation Low Quiescent Current The MAX4409 draws only 5mA of supply current, deliv- ers up to 80mW per channel into a 16 load, and has a Low-Power Shutdown Mode low 0.002% THD+N. A high 86dB power-supply rejec- Short-Circuit and Thermal-Overload Protection tion ratio allows this device to operate from noisy digital 8kV ESD-Protected Amplifier Outputs supplies without additional power-supply conditioning. Available in a Space-Saving Package The MAX4409 includes 8kV ESD protection on the 20-Pin Thin QFN (4mm x 4mm x 0.8mm) headphone outputs. Comprehensive click-and-pop cir- cuitry eliminates audible clicks and pops on startup and shutdown. A low-power shutdown mode reduces Ordering Information supply current draw to only 6A. The MAX4409 operates from a single 1.8V to 3.6V sup- PART TEMP RANGE PIN-PACKAGE ply, has short-circuit and thermal overload protection, MAX4409ETP -40C to +85C 20 Thin QFN-EP* and is specified over the extended -40C to +85C tem- *EP = Exposed pad. perature range. The MAX4409 is available in a tiny 20- pin thin QFN (4mm x 4mm x 0.8mm) package. Applications Functional Diagram Notebooks DirectDrive OUTPUTS Desktop PCs ELIMINATE DC-BLOCKING MAX4409 CAPACITORS LEFT Cellular Phones AUDIO INPUT PDAs MP3 Players Tablet PCs SHDN Portable Audio Equipment COM RIGHT DirectDrive is a registered trademark of Maxim Integrated COMMON-MODE AUDIO Products, Inc. SENSE INPUT ELIMINATES INPUT GROUND-LOOP NOISE Pin Configurations and Typical Application Circuit appear at end of data sheet. 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.com80mW, DirectDrive, Stereo Headphone Amplifier with Common-Mode Sense ABSOLUTE MAXIMUM RATINGS PGND to SGND .....................................................-0.3V to +0.3V Output Short Circuit to GND or V ...........................Continuous DD PV to SV -0.3V to +0.3V Thermal Limits (Note 1) DD DD ................................................................. PV to SV .........................................................-0.3V to +0.3V Continuous Power Dissipation (T = +70C) SS SS A PV and SV to PGND or SGND .........................-0.3V to +4V 20-Pin Thin QFN Multilayer (derate 25.6mW/C DD DD PV and SV to PGND or SGND ..........................-4V to +0.3V above +70C)..........................................................2051mW SS SS IN and COM to SGND.................................SV to (SV - 1V) ................................................................................39C/W SS DD JA IN to COM .....................................(COM + 2V) to (COM - 0.3V) ...............................................................................5.7C/W JC SHDN to SGND........................(SGND - 0.3V) to (SV + 0.3V) Junction Temperature......................................................+150C DD OUT to SGND ............................(SV - 0.3V) to (SV + 0.3V) Operating Temperature Range ...........................-40C to +85C SS DD C1P to PGND.............................(PGND - 0.3V) to (PV + 0.3V) Storage Temperature Range .............................-65C to +150C DD C1N to PGND .............................(PV - 0.3V) to (PGND + 0.3V) Lead Temperature (soldering, 10s) .................................+300C SS Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a 4-layer board. For detailed information on package thermal considerations see www.maxim-ic.com/thermal-tutorial. 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 = V = 3V, V = V = 0, SHDN = SV , C1 = C2 = 2.2F, R = R = R1 = R2 = 10k, R = , T = T to PVDD SVDD PGND SGND DD IN F L A MIN T , unless otherwise noted. Typical values are at T = +25C.) (Note 2) MAX A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Supply Voltage Range V Guaranteed by PSRR test 1.8 3.6 V DD Quiescent Supply Current I 5 8.4 mA DD Shutdown Supply Current I SHDN = GND 6 10 A SHDN 0.7 x V IH SV DD SHDN Thresholds V 0.3 x V IL SV DD SHDN Input Leakage Current -1 +1 A SHDN to Full Operation t 175 s SON CHARGE PUMP Oscillator Frequency f 272 320 368 kHz OSC AMPLIFIERS Input Offset Voltage V R = 32 0.5 2.4 mV OS L Input Bias Current I -700 -100 0 nA BIAS COM Bias Current I -1400 -200 0 nA COM Equivalent Input Offset Current I I = (I + I - I ) / 2 2 nA OS OS BIAS(INR) BIAS(INL) COM COM Input Range V Inferred from CMRR test -500 +500 mV COM Common-Mode Rejection Ratio CMRR -500mV V +500mV, R 10 75 96 dB COM SOURCE 1.8V V 3.6V DC (Note 3) 75 86 DD Power-Supply Rejection Ratio PSRR f = 1kHz 76 dB V = 3.0V, RIPPLE DD 200mV ripple (Note 4) P-P f = 20kHz 48 RIPPLE R = 32 65 L Output Power P THD+N = 1%, T = +25C mW OUT A R = 16 55 80 L 2 MAX4409