DATA SHEET AAT1219 High Current Step-Up Converter with Adjustable Current Limit General Description Features V Range: 2.4V to V + 0.25V The AAT1219 is a high current synchronous boost con- IN OUT V Range verter with programmable low side MOSFET peak current OUT Adjustable and Fixed Voltage Versions limit of 500mA to 2.5A. It is ideal for preventing input Adjustable: 3.0V to 5.0V current from overloading system power in PCI-E card Programmable NMOS Peak Current Limit: 500mA to applications based on WCDMA/Edge/GPRS/TD-SCDMA 2.5A PCI-E card GSM high load pulse applications. With a suit- Startup Inrush Current Limit: 500mA able UltraCap or SuperCap, the AAT1219 ensures that Reverse Current Blocking output voltage meets load power requirements when True Load Disconnect when Shutdown large load pulses are applied. It is also ideal for CDMA/ Up to 95% Efficiency Evdo-A/Evdo-B and other industry modem continuous 1.2MHz Switching Frequency load current applications. Low R DS(ON) The output voltage of the adjustable version of the Synchronous Boost Rectification and Internal AAT1219 is programmed from 3.0V to 5.0V by an exter- Compensation nal resistive divider the FB pin is left floating in the fixed Output Ready Indicator output voltage version. Optimized internal compensation Fault Protection provides fast transient response with no external compo- Programmable Over-Voltage Protection nents. Light load switching frequency modulation and Short-Circuit Protection low quiescent current maintain high efficiency perfor- Over-Temperature Protection mance for light load mode conditions. Low-profile TDFN33-12 Package The low-side power MOSFET peak current limit of 500mA to 2.5A is set via an external resistor to protect the sys- Applications tem power from overload. The high-side current limit operates in a linear mode to limit inrush current to PC Cards (PCMCIA) Modems 500mA. PCI-E Modem Cards WCDMA/Edge/GPRS/TD-SCDMA Reverse blocking is integrated to prevent current from CDMA/Evdo-A/Evdo-B flowing back to the input. The AAT1219 s true load discon- Industry Modems nect function isolates the output from the input when the USB Modems device is disabled. Output over-voltage, short-circuit, and over-temperature protection are also integrated to pro- tect the AAT1219 from these fault conditions. The AAT1219 is available in a Pb-free, 12-pin, low-profile TDFN33 package and is rated over the -40C to 85C temperature range. Skyworks Solutions, Inc. Phone 781 376-3000 Fax 781 376-3100 sales skyworksinc.com www.skyworksinc.com 1 202052A Skyworks Proprietary Information Products and Product Information are Subject to Change Without Notice. June 12, 2012 DATA SHEET AAT1219 High Current Step-Up Converter with Adjustable Current Limit Typical Application 2.4V to V +0.25V OUT L1 4.7H LX V 3.8V OUT VIN OUT High Load Pulse C IN 10F R 1 C C OUT1 OUT2 AAT1219 316k R 3 22F UltraCap 100k FB or SuperCap R 2 RDY 59k EN ISET OVP AGND PGND R SET 2.4V to V +0.25V OUT L1 4.7H LX V 3.5V OUT VIN OUT Continuous Load C IN 10F R 1 C OUT1 AAT1219 287k R 3 22F 100k FB R 2 RDY 59k EN ISET OVP AGND PGND R SET 40.2k Pin Descriptions Pin Symbol Description 4 IN Battery input voltage. Supplies the IC at startup. Switching node tied to drain of internal N-channel MOSFET and source of internal P-channel MOSFET. Con- 1,2 LX nect this pin to the external power inductor. Feedback input pin.This pin is connected to an external resistor divider which programs the output voltage 8FB for adjustable version with feedback voltage of 0.6V. Boost converter output voltage connects to the P-channel synchronous MOSFET source. Bypass with ceramic 10 OUT capacitor to GND. 11, 12 PGND Power ground. 7 AGND Non-power signal ground pin. 3 EN Input enable pin. Logic high to enable the boost. Logic low to disable the IC. 6 RDY System ready pin. Open drain, active low, initiated when the output capacitor is 95% charged. Peak current limit programmable input. An external resistor from ISET to ground is adopted to program the 9 ISET low-side MOSFET peak current limit between 500mA and 2.5A. Over voltage protection pin.This pin is connected to an external resistor divider to set the over voltage 5 OVP threshold.To disable the over voltage feature, short this pin to ground. Skyworks Solutions, Inc. Phone 781 376-3000 Fax 781 376-3100 sales skyworksinc.com www.skyworksinc.com 2 202052A Skyworks Proprietary Information Products and Product Information are Subject to Change Without Notice. June 12, 2012