The operating current level is user-programmable via an external current sense resistor. Wide input supply range allows operation from 3.5V to 18V (20V maximum). Constant off-time architecture provides low dropout regulation limited only by the RDS(ON) of the topside MOSFET (when using the P-channel) and the resistance of the inductor and current sense resistor. The LTC1266 series combines synchronous switching for maximum efficiency at high currents with an automatic low current operating mode, called Burst Mode operation, which reduces switching losses. Standby power is reduced to only 1mW at VIN = 5V (at IOUT = 0). Load currents in Burst Mode operation are typically 0mA to 500mA. , LTC and LT are registered trademarks of Linear Technology Corporation. Burst Mode is a trademark of Linear Technology Corporation.