LM2772

LM2772 Low-Ripple Switched Capacitor Step-Down Regulator December 2006 LM2772 Low-Ripple Switched Capacitor Step-Down Regulator General Description The LM2772 is a switched capacitor step-down regulator that produces a 1.2V output. It is capable of supplying loads up to 150mA with 3% output voltage regulation over line, load, and temperature. The LM2772 operates with an input voltage from 3.0V to 5.5V, accommodating 1-cell Li-Ion batteries and chargers. The LM2772 utilizes a highly efficient regulated multi-gain charge pump. Pre-regulated 1.1MHz fixed-frequency switching results in very low ripple and noise on both the input and the output. When output currents are low, the part automatically switches to a low-ripple PFM regulation mode to maintain high efficiency over the entire load range. The LM2772 is available in National’s 10-pad Leadless Leadframe No-Pullback Package (LLP-10). Features ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ Low-Noise Fixed Frequency Operation 1.2V Output Voltage 3% Output Voltage Regulation Li-Ion (3.6V) to 1.2V with 80% Efficiency Very Low Output Ripple: 8mV @ 150mA Output Currents up to 150mA 2.7V to 5.5V Input Voltage Range Shutdown Disconnects Load from VIN 1.1MHz Switching Frequency No Inductors…Small Solution Size Short Circuit and Thermal Protection LLP-10 Package (3mm × 3mm × 0.8mm) Applications ■ DSP, Memory, and Microprocessor Power Supplies ■ Mobile Phones and Pagers ■ Portable Electronic Devices Typical Application Circuit LM2772 Efficiency vs. Low-...