Linear Technology Corporation has introduced the LT3505, a current-mode pulse width modulation (PWM) step-down dc/dc converter with an internal 1.75 A power switch and up to 1.2 A output current. Packaged in an 8-lead, 3mm x 3mm DFN, the device features a 3.6 V to 36 V input range and can withstand 40 V transients.
The LT3505 is designed to regulate power from a variety of sources, including automotive batteries. In automotive applications, the part's 3.6 V minimum input voltage enables it to operate with sub-4 V inputs and to meet "cold crank" requirements. Its 40 V input capability enables it to withstand transients found in load-dump conditions. The LT3505 switching frequency is programmable from 200 kHz to 3 MHz, thus it can maximize efficiency while using tiny, low-cost inductors and ceramic capacitors, for low, predictable output ripple.