Linear Technology - Ultra low-noise power supply ripple rejection LDO (LT3042)

Linear Technology's LT3042 high-performance, low-dropout, linear regulator with ultra-low noise and ultra-high PSRR architecture can power noise-sensitive RF applications. The LT3042 is designed as a precision current reference, followed by a high-performance voltage buffer that can be easily paralleled to further reduce noise, increase output current and dissipate heat on the PCB. The device delivers 200mA at a typical 350mV dropout voltage. The operating quiescent current is nominally 2mA and drops to less than 1μA at shutdown. The LT3042's wide output voltage range (0V to 15V) provides almost constant output noise, PSRR, bandwidth, and load regulation while maintaining unity gain operation, regardless of the programmed output voltage. In addition, the regulator has a programmable current limit, a fast start function and a programmable power supply, which can well indicate the regulation of the output voltage. The LT3042 is stabilized with a minimum 4.7μF ceramic output capacitor. Built-in protection includes reverse battery protection, reverse current protection, internal current limit with foldback and thermal limit with hysteresis. The LT3042 is available in a thermally enhanced 10-lead MSOP and a 3mm x 3mm DFN package.