DATA SHEET AAT2215 High Current Synchronous Step-Up Regulator with Programmable Current Limit General Description Features The AAT2215 SwitchReg is a high current, synchronous 2.4V to V + 0.25V Input Voltage Range OUT step-up converter with a programmable peak NMOS cur- Adjustable 3.0V to 5.5V Output Voltage rent limit. It is ideal to prevent the input current from Internal Compensation overloading the system power in PC Card GSM/GPRS/3G 600kHz Switching Frequency and WiMax modem card applications. The AAT2215 s Programmable Peak NMOS Current Limit internal compensation is optimized for the large bulk (0.6A to 4.0A) tantalum output capacitors needed to support the output Synchronous P-Channel MOSFET voltage during large load pulses. True Load Disconnect in Shutdown Reverse Current Block When Enabled The output voltage may be programmed from 3.0V to Start-Up Inrush Current Limit (0.75A) and Overload 5.5V by external resistor divider. Light load switching Current Limit (3A) frequency modulation and low quiescent current main- Up to 95% Efficiency tain high efficiency performance for light load mode Active-Low Power Ready Indicator (RDY) conditions. Very Low 55A No-Load Operating Current Two current limits are designed into the AAT2215. One is Less than 1A Shutdown Current the low-side power MOSFET programmable peak current 6V Output Over-Voltage Protection (OVP) limit, which works when the device is in step-up regula- Thermal Shutdown Protection (TSHDN) tion state. An external resistor is used to program the Short Circuit Protection current limit from 600mA to 4.0A. The other is the high- Low-Profile TDFN33-12 Package side current limit, which operates in a linear mode to limit inrush current to 750mA when the output charges Applications up to the input voltage. The AAT2215 includes internal over-voltage protection and a system ready signal. Media Tablets PCI-Express Cards The AAT2215 is available in a Pb-free, 3mm x 3mm, PCMCIA Cards 12-pin TDFN package (TDFN33-12) rated from -40C to Modems +85C. Wireless Data Cards Typical Application Figure L1 2.2H V IN 2.4V to V + 0.25V OUT V OUT IN LX 3.8V R RDY C IN OUT 100k 10F C AAT2215 R OUT FB1 22F 536k RDY FB ON R FB2 EN OFF 100k R SET AGND 100k RSET PGND Skyworks Solutions, Inc. Phone 781 376-3000 Fax 781 376-3100 sales skyworksinc.com www.skyworksinc.com 202062A Skyworks Proprietary Information Products and Product Information are Subject to Change Without Notice. June 14, 2012 1DATA SHEET AAT2215 High Current Synchronous Step-Up Regulator with Programmable Current Limit Pin Descriptions Pin Name Function Inductor switching node. LX is internally connected to the source of the internal low-side N-channel 1, 2 LX MOSFET (NMOS), and synchronous high-side P-channel MOSFET (PMOS). Externally connected to the switching side of the power inductor as shown in the Typical Application drawing. Enable input. A logic high enables the AAT2215 regulator. A logic low forces the AAT2215 into shut- 3EN down mode, placing the output into a high-impedance state (true load disconnect) and reducing the quiescent current to less than 1A. Input supply. IN powers the analog control circuitry during start-up. Bypass IN to GND with a 10F or 4IN greater ceramic capacitor. Power ready signal (active low). RDY is an open-drain, active-low output. RDY is pulled low when the 5 RDY feedback voltage exceeds 95% of the target voltage. 6 AGND Analog ground. AGND is internally connected to the analog ground of the control circuitry. Feedback input. FB senses the output voltage for regulation control. For adjustable output versions, 7FB connect a resistive divider network from the output to FB to GND to set the output voltage accordingly. The FB regulation threshold is 0.6V. Programmable current-limit control. Connect an external resistor between RSET and AGND to set the 8 RSET peak NMOS current-limit threshold. The current-limit threshold may be adjusted from 0.6A to 4.0A.9 9, 10 OUT Output of step-up regulator. OUT internally connects to the synchronous high-side P-channel MOSFET. 11, 12 PGND Power ground. PGND is internally connected to the source of the low-side N-channel MOSFET. Substrate/thermal ground. The exposed pad is internally connected to the substrate of the controller, EP Exposed Pad and provides the lowest thermal impedance between the regulator and the PCB. Connect the exposed pad directly to the ground plane to reduce thermal stress. Pin Configuration TDFN33-12 (Top View) 1 12 LX PGND 2 11 LX PGND 3 10 EN OUT 4 9 IN OUT 5 8 RDY RSET 6 7 AGND FB Skyworks Solutions, Inc. Phone 781 376-3000 Fax 781 376-3100 sales skyworksinc.com www.skyworksinc.com 2 202062A Skyworks Proprietary Information Products and Product Information are Subject to Change Without Notice. June 14, 2012