MAX9728B

19-3963; Rev 1; 7/09 KIT ATION EVALU ABLE AVAIL 60mW, DirectDrive, Stereo Headphone Amplifiers with Shutdown General Description Features ♦ No Bulky DC-Blocking Capacitors Required ♦ Low-Power Shutdown Mode, < 0.1µA ♦ Adjustable Gain (MAX9728A) or Fixed -1.5V/V Gain (MAX9728B) ♦ Low 0.02% THD+N ♦ High PSRR (80dB at 1kHz) Eliminates LDO ♦ Integrated Click-and-Pop Suppression ♦ 4.5V to 5.5V Single-Supply Operation ♦ Low Quiescent Current (3.5mA) ♦ Available in Space-Saving Packages 12-Pin Thin QFN (3mm x 3mm x 0.8mm) 14-Pin TSSOP (5mm x 4.4mm x 1.1mm) MAX9728A/MAX9728B The MAX9728A/MAX9728B stereo headphone amplifiers are designed for display and notebook applications or portable equipment where board space is at a premium. These devices use a unique, patented DirectDrive™ architecture to produce a ground-referenced output from a single supply, eliminating the need for large DC-blocking capacitors, saving cost, board space, and component height. The MAX9728A offers an externally adjustable gain, while the MAX9728B has an internally preset gain of -1.5V/V. The MAX9728A/ MAX9728B deliver up to 60mW per channel into a 32Ω load and have low 0.02% THD+N. An 80dB at 1kHz power-supply rejection ratio (PSRR) allows these devices to operate from noisy digital supplies without an additional linear regulator. Comprehensive clickand-pop circuitry suppresses audible clicks and pops on startup and shutdown. The MAX9728A/MAX9728B operate from a single 4.5V to 5.5V supply, consume only 3.5mA of supply current, feature short-circuit and thermal-overload protection, and are specified over the extended -40°C to +85°C temperature range. The devices are available in tiny 12pin Thin QFN (3mm x 3mm x 0.8mm) and 14-pin TSSOP packages (5mm x 4.4mm x 1.1mm). Ordering Information PART MAX9728AETC+ MAX9728AEUD+ MAX9728BETC+ MAX9728BEUD+ GAIN (V/V) PIN-PACKAGE Adj. Adj. -1.5 -1.5 12 TQFN-EP* 14 TSSOP 12 TQFN-EP* 14 TSSOP TOP MARK ABC — ABD — Applications Notebook PCs DVD Players LCD/PDP Displays Pin Configurations appear at end of data sheet. CRT TVs Multimedia Monitors Note: All devices specified over the -40°C to +85°C operating range. +Denotes lead(Pb)-free/RoHS-compliant package. *EP = Exposed pad. Block Diagrams MAX9728B MAX9728A LEFT AUDIO INPUT DirectDrive OUTPUTS ELIMINATE DC-BLOCKING CAPACITORS LEFT AUDIO INPUT DirectDrive OUTPUTS ELIMINATE DC-BLOCKING CAPACITORS SHDN SHDN RIGHT AUDIO INPUT RIGHT AUDIO INPUT FIXED GAIN ELIMINATES EXTERNAL RESISTOR NETWORK ________________________________________________________________ Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. 60mW, DirectDrive, Stereo Headphone Amplifiers with Shutdown MAX9728A/MAX9728B ABSOLUTE MAXIMUM RATINGS VDD to GND ..............................................................-0.3V to +6V PVSS to SVSS .........................................................-0.3V to +0.3V PGND to SGND .....................................................-0.3V to +0.3V C1P to PGND..............................................-0.3V to (VDD + 0.3V) C1N to PGND............................................(PVSS - 0.3V) to +0.3V PVSS and SVSS to PGND..........................................-6V to +0.3V IN_ to SGND (MAX9728A)..........................-0.3V to (VDD + 0.3V) IN_ to SGND (MAX9728B) .............(SVSS - 0.3V) to (VDD + 0.3V) OUT_ to SVSS (Note 1) ....-0.3V to Min (VDD - SVSS + 0.3V, +9V) OUT_ to VDD (Note 2) ......+0.3V to Max (SVSS - VDD - 0.3V, -9V) SHDN to _GND.........................................................-0.3V to +6V OUT_ Short Circuit to GND ........................................Continuous Short Circuit between OUTL and OUTR ....................Continuous Continuous Input Current into PVSS ..................................260mA Continuous Input Current (any other pin) .........................±20mA Continuous Power Dissipation (TA = +70°C) 12-Pin TQFN (derate 14.7mW/°C above +70°C) .........1177mW 14-Pin TSSOP (derate 9.1mW/°C above +70°C) ...........727mW Operating Temperature Range ...........................-40°C to +85°C Storage Temperature Range .............................-65°C to +150°C Junction Temperature ......................................................+150°C Lead Temperature (soldering, 10s) .................................+300°C Note 1: OUTR and OUTL should be limited to no more than 9V above SVSS, or above VDD + 0.3V, whichever limits first. Note 2: OUTR and OUTL should be limited to no more than 9V below VDD, or below SVSS - 0.3V, whichever limits first. 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 (VDD = 5V, PGND = SGND, SHDN = 5V, C1 = C2 = 1µF, RL = ∞, resistive load reference to ground; for MAX9728A gain = -1.5V/V (RIN = 20kΩ, RF = 30kΩ); for MAX9728B gain = -1.5V/V (internally set), TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C, unless otherwise noted.) (Note 3) PARAMETER GENERAL Supply Voltage Range Quiescent Current Shutdown Current Shutdown to Full Operation Input Impedance Output Offset Voltage Power-Supply Rejection Ratio VDD ICC ISHDN tSON RIN VOS VDD = 4.5V to 5.5V PSRR f = 1kHz, 100mVP-P f = 20kHz, 100mVP-P Output Power Voltage Gain Channel-to-Channel Gain Tracking Total Harmonic Distortion Plus Noise THD+N POUT AV RL = 32Ω, THD+N = 1% RL = 16Ω, THD+N = 1% MAX9728B (Note 4) MAX9728B RL = 1kΩ, VOUT = 2VRMS, fIN = 1kHz RL = 32Ω, POUT = 50mW, fIN = 1kHz RL = 16Ω, POUT = 35mW, fIN = 1kHz -1.52 30 MAX9728B, measured at IN_ 15 SHDN = SGND = PGND 4.5 3.5