DATA SHEET AAT1184 High Voltage Step-Down Regulator General Description Features The AAT1184 is a single output step-down (Buck) DC V = 6.0 to 24.0V IN output regulator with an integrated high side MOSFET. V Adjustable from 1.5V to 5.5V OUT The input range is 6V to 24V making it the ideal power IC I up to 1.2A OUT solution for consumer communications equipment oper- Small Solution Size ating from a low cost AC/DC adapter with 12V output. Low-Cost Non-Synchronous Solution Shutdown Current <35A The step-down regulator provides up to 1.2A output cur- High Switching Frequency rent in a small package. 490kHz fixed switching fre- Voltage Mode Control quency allows small L/C filtering components. PWM Fixed Frequency for Lowest Noise Voltage mode control allows for optimum performance Programmable Over-Current Protection across the entire output voltage and load range. Over-Temperature Protection Internal Soft Start The controller includes programmable over-current, inte- Low Profile 3x3mm TSOPJW-12 Package grated soft-start and over-temperature protection. -40C to 85C Temperature Range The AAT1184 is available in the Pb-free, low profile 12-pin TSOPJW package. The rated operating tempera- Applications ture range is -40C to 85C. DSL and Cable Modems Notebook Computers Satellite Set Top Box Wireless LAN Systems Typical Application V IN TSOPJW -12 6V - 24V IN BST L1 V C2 OUT 4.7H 0.1F 5V/1.2A LX D1 C7 D2 BAS16 EN 330pF R1 B340A + R4 2.32K C1 C12 RS 44.2k 25F 1F AAT1184 25V 25V R7 C4 C8 499 22F 68nF OS VL FB R2 C5 C3 24.3K 220pF R5 2.2F COMP 6.04k C6 56pF GND Skyworks Solutions, Inc. Phone 781 376-3000 Fax 781 376-3100 sales skyworksinc.com www.skyworksinc.com 1 202000A Skyworks Proprietary Information Products and Product Information are Subject to Change Without Notice. May 29, 2012 DATA SHEET AAT1184 High Voltage Step-Down Regulator Pin Descriptions Pin Symbol Function Output current sense pin. Connect a small signal resistor from this pin to switching node (LX) to en- 1RS able over-current sense for step-down converter. 2 EN Enable input pin. Active high. Boost drive input pin. Connect the cathode of fast recti er from this pin and connect a 100nF ca- 3 BST pacitor from this pin to the switching node (LX) for internal hi-side MOSFET gate drive. 4, 5 LX Step-down converter switching pin. Connect output inductor to this pin. Connect LX pins together. Input supply voltage pin for step-down regulator. Connect both IN pins together. Connect the input 6, 7 IN capacitor close to this pin for best noise performance. 8 VL Internal linear regulator. Connect a 2.2F/6.3V capacitor from this pin to GND pin. Ground pin for step-down converter. Connect input and output capacitors return terminals close to 9 GND this pin for best noise performance. Feedback input pin for step-down converter. Connect an external resistor divider to this pin to pro- 10 FB gram the output voltage to the desired value. Compensation pin for step-down regulator. Connect a series resistor, capacitor network to compen- 11 COMP sate the voltage mode control loop. Output voltage sense pin. Connect to the output capacitor to enable over-current sense for step- 12 OS down converter. Pin Configuration TSOPJW-12 (Top View) 1 12 RS OS 2 11 EN COMP 3 10 BST FB 4 9 LX GND 5 8 LX VL 6 7 IN IN Skyworks Solutions, Inc. Phone 781 376-3000 Fax 781 376-3100 sales skyworksinc.com www.skyworksinc.com 2 202000A Skyworks Proprietary Information Products and Product Information are Subject to Change Without Notice. May 29, 2012