Step-Down Converters Reduce Size, Simplify Design

Available in 3 mm x 3 mm packages, the AAT1112 and AAT1145 constant frequency current mode step-down converters require no external compensation components, promising users a compact and easy-to-implement solution. Both devices allow a lithium-ion battery to deliver a 3.3V output at full current. The AAT1112 supplies up to 1.5A output current from a 2.4V to 5.5V input, while the AAT1145 delivers up to 1.2A from a 2.5V to 5.5V input. Output voltage ranges from 0.6V to the input voltage. They also extend battery life by running at 100% duty cycle for low dropout operation and offering efficiencies up to 95%. Other shared features include slope-compensated current mode PWM control, 1.5 MHz and 1.4 MHz switching frequencies, soft start, short-circuit and thermal-fault protection, and a shutdown current of less than 1 mA. The AAT1112 comes in either a 12-lead TDFN or TSOPJW, and the AAT1145 comes in a 10-lead TDFN package. All versions are lead free. Depending on the device and package, prices range from $1.51 to $1.64 each/1,000. ADVANCED ANALOGIC TECHNOLOGIES INC., Sunnyvale, CA. (408) 737-4600.