MAX98502 19-6145 Rev 0 12/11 Boosted 2.2W Class D Amplifier with Automatic Level Control General Description Features The MAX98502 is a high-efficiency, Class D audio ampli- S Boosted Class D Output fier that features an integrated boost converter to deliver S Integrated Automatic Level Control a constant output power over a wide range of battery S Output Power supply voltages. 2.2W into 8I, 10% THD+N The boost converter operates at 2MHz, requiring only a 1.7W into 8I, 1% THD+N small (2.2FH) external inductor and capacitor. 4.1W into 4I, 10% THD+N The automatic level control has a battery tracking func- 3.4W into 4I, 1% THD+N tion that reduces the output swing as the supply voltage S Wide 2.5V to 5.5V Supply Voltage Range drops, preventing collapse of battery voltage. S Undervoltage Lockout Protection The amplifier has differential inputs and an internal fully S High Total Efficiency of 87% differential design. The MAX98502 also features three S High Step-Up Switching Frequency (2MHz) gain settings (6dB, 15.5dB, and 20dB) that are select- able with a logic input. S Active Emission Limiting for Low EMI The MAX98502 is available in a small, 0.5mm pitch 16-bump WLP package (2.1mm x 2.1mm). It is specified over the extended -40NC to +85NC temperature range. Ordering Information Applications PART TEMP RANGE PIN-PACKAGE Cell Phones MAX98502EWE+ -40NC to +85NC 16 WLP Smartphones +Denotes a lead(Pb)-free/RoHS-compliant package. GPS Devices Typical Application Circuit appears at end of data sheet. Mobile Internet Devices Active Speaker Accessories Simplified Block Diagram BATTERY V LX BAT B4 A3 V CCOUT A2 BOOST CONVERTER SDBST D4 SDSPK C3 CONTROL MAX98502 GAIN B2 A1 PVDD RKNEE B3 B1 SPKP INP D2 DIFFERENTIAL OUTPUT GAIN C1 SPKN INN D3 INPUT STAGE C4 A4 D1, C2 AGND BSTPGND SPKPGND 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.Boosted 2.2W Class D Amplifier with Automatic Level Control ABSOLUTE MAXIMUM RATINGS V to AGND .........................................................-0.3V to +6V Duration of SPK Short Circuit to PVDD or BAT SPKPGND ..............................................................Continuous V to BSTPGND, AGND .................................-0.3V to +6V CCOUT PVDD to SPKPGND .................................................-0.3V to +6V Duration of Short Circuit Between SPKP and SPKN ..............................................................Continuous BSTPGND, SPKPGND to AGND ......................... -0.3V to +0.3V Continuous Power Dissipation, Multilayer Board (T = +70NC) GAIN to AGND ........................................-0.3V to (V + 0.3V) A BAT SDBST, SDSPK to AGND ........................................-0.3V to +6V WLP (derate 20.4mW/NC above +70NC)........................1.33W Junction Temperature .....................................................+150NC All Other Pins (excluding LX) to AGND ..................-0.3V to +6V Operating Temperature Range .......................... -40NC to +85NC Current Into/Out of LX, V , BSTPGND .....................Q3.9A CCOUT Storage Temperature Range ............................ -65NC to +150NC Continuous Current Into/Out of SPK , PVDD, Soldering Temperature (reflow) ......................................+260NC SPKPGND ..................................................................Q800mA Continuous Input Current (all other pins) ........................Q20mA Duration of Short Circuit Between V CCOUT and BSTPGND ...................................................... Continuous PACKAGE THERMAL CHARACTERISTICS (Note 1) WLP Junction-to-Ambient Thermal Resistance (q ) ..........49C/W JA Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four- layer board. For detailed information on package thermal considerations, refer to 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 = 3.6V, R = J between SPKP and SPKN, A = +6dB, C = 1FF, 20Hz to 22kHz AC measurement bandwidth, T = T to BAT L V IN A MIN T , unless otherwise noted. Typical values are at T = +25NC.) (Note 2) MAX A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Power-Supply Rejection Ratio PSRR T = +25NC, V = 2.5V to 5.5V 95 dB A BAT (Note 3) 3.7 T = +25NC, SDSPK = SDBST = V A BAT I VBAT 0.1 0.15 T = +25NC, V = 0V, SDBST = V A SDSPK BAT Quiescent Current mA T = +25NC, PVDD = 5.55V, SDSPK = A I 1.7 2.7 PVDD SDBST = V BAT Combined Efficiency E P = 1.7W, f = 1kHz, Z = 8I + 68FH 87 % OUT SPK Shutdown Current I V = V = 0V, T = +25NC 0.04 1.5 FA SHDN SDSPK SDBST A Turn-On Time t Time from power-on to full operation 10 12 ms ON BOOST CONVERTER Battery Supply Voltage Range V 2.5 5.5 V BAT Soft-Start Interval t 5.6 ms ON Undervoltage Lockout UVLO V falling 2.1 2.2 2.3 V BAT Boost Converter Output Voltage V I = 0mA 5.45 5.5 5.65 V VCCOUT LOAD Output Current Limit I V R = 3.6V 1.5 A MAX BAT Input Current Limit I Startup, V = 0V 0.3 0.5 A LIMIT CCOUT nMOS Current Limit I 3.3 A LX,MAX pMOS Turn-Off Current Limit 10 mA 2 MAX98502