DATA SHEET AAT2713 Low Noise, Dual 600mA Step-Down Converter with Synchronization General Description Features The AAT2713 is a high efficiency dual synchronous step- V Range: 2.7V to 5.5V IN down converter for applications where power efficiency, Low Noise Light Load Mode thermal performance and solution size are critical. Input Low Ripple PWM Mode voltage ranges from 2.7V to 5.5V, making it ideal for Output Current: systems powered by single-cell lithium-ion/polymer bat- Channel 1: 600mA teries. The AAT2713 incorporates a unique low noise Channel 2: 600mA architecture which reduces ripple and spectral noise. 96% Efficient Step-Down Converter Low No Load Quiescent Current Each converter is capable of 600mA output current and 70A Total for Both Converters has its own enable pin. Efficiency of the converters is Integrated Power Switches optimized over full load range. Total no load quiescent 100% Duty Cycle current is 70A, allowing high efficiency even under light 1.7MHz Switching Frequency load conditions. Optional Fixed Frequency or External SYNC The integrated power switches are controlled by pulse Logic Selectable 180 Phase Shift Between the Two width modulation (PWM) with a 1.7MHz typical switching Converters frequency at full load, which minimizes the size of exter- Current Limit Protection nal components. Fixed frequency, low noise operation Automatic Soft-Start can be forced by a logic signal on the MODE pin. Over-Temperature Protection Furthermore, an external clock can be used to synchro- QFN33-16 Package nize the switching frequency of both converters. -40C to +85C Temperature Range A phase shift pin (PS) is available to operate the two converters 180 out of phase at heavy load to achieve Applications low input ripple. Cellular Phones / Smart Phones The AAT2713 is available in a Pb-free, thermally Digital Cameras enhanced 16-pin QFN33 package and is specified for Handheld Instruments operation over the -40C to +85C temperature range. Micro Hard Disc Drives Microprocessor / DSP Core / IO Power PDAs and Handheld Computers Typical Application L1 VIN1 VOUT1 Input: VIN2 LX1 2.7V to 5.5V 2.2 H R1 VCC C IN FB1 1 F L2 AAT2713 VOUT2 C2 R2 LX2 4.7 F 2.2 H R3 MODE/SYNC C1 PS FB2 4.7 F EN1 R4 EN2 AGND PGND1 PGND2 Skyworks Solutions, Inc. Phone 781 376-3000 Fax 781 376-3100 sales skyworksinc.com www.skyworksinc.com 1 202036A Skyworks Proprietary Information Products and Product Information are Subject to Change Without Notice. June 8, 2012 PGND1 LX1 N/C VIN1 13 8 PGND2 14 7 LX2 15 6 N/C 16 5 VIN2 DATA SHEET AAT2713 Low Noise, Dual 600mA Step-Down Converter with Synchronization Pin Descriptions Pin Symbol Function Phase shift pin. Logic high enables the PS feature which forces the two converters to operate 1PS 180 out of phase when both are in forced PWM mode. Analog ground. Return the feedback resistive divider to this ground. See section on PCB layout 2 AGND guidelines and evaluation board layout diagram. Feedback input pins. An external resistive divider ties to each and programs the respective out- 4, 3 FB1, FB2 put voltage to the desired value. 5, 16 VIN1, VIN2 Input supply voltage pins. Must be closely decoupled to the respective PGND. 6, 15 N/C Not connected 7, 14 LX1, LX2 Output switching nodes that connect to the respective output inductor. Main power ground return. Connect to the input and output capacitor return. See section on PCB 8, 13 PGND1, PGND2 layout guidelines and evaluation board layout diagram. Converter enable input pins. A logic high enables the converter channel. A logic low forces the channel into shutdown mode, reducing the channel supply current to less than 1A. This pin 10, 9 EN1, EN2 should not be left oating. When not actively controlled, this pin can be tied directly to VIN and/ or VCC. 11 VCC Control circuit power supply. Connect to the higher voltage of VIN1 or VIN2. Logic low enables light load mode operation for light loads and xed-frequency PWM operation 12 MODE/SYNC for heavy loads. Logic high forces low noise PWM operation under all operating conditions. Con- nect to an external clock for synchronization (PWM only). Exposed paddle (bottom). Use properly sized vias for thermal coupling to the ground plane. See EP section on PCB layout guidelines. Pin Configuration QFN33-16 (Top View) 1 12 PS MODE/SYNC 2 11 VCC AGND 3 10 EN1 FB2 4 9 FB1 EN2 Skyworks Solutions, Inc. Phone 781 376-3000 Fax 781 376-3100 sales skyworksinc.com www.skyworksinc.com 2 202036A Skyworks Proprietary Information Products and Product Information are Subject to Change Without Notice. June 8, 2012