Dual linear LDO regulator with independent inputs offers very low noise



Linear Technology announced the release of the LT3030, a dual low noise, low dropout regulator with independent inputs and independent shutdown control for each channel. The device delivers continuous output current up to 750mA on one channel and 250mA on the other channel, with a low dropout voltage of only 300mV at full load. With a wide 1.8V to 20V input voltage range, the device delivers output voltages as low as 1.215V and up to 19.5V. Features include a low 20μVRMS noise across a wide 10Hz to 100kHz bandwidth, a precision shutdown/UVLO threshold for each channel, tracking/sequencing capability and dual PWRGD flags to indicate output regulation per channel. The LT3030's full feature set and low quiescent current of 115μA/70μA per regulator (operating) and <1μA each (in shutdown) make it ideal for battery-powered "keep alive" systems that require optimum run time, as well as microprocessor core logic supplies, tracking/sequencing supplies and general-purpose voltage conversion. The LT3030 operates with very small, low cost, ceramic output capacitors, optimizing stability and transient response. It is stable with only a 10μF ceramic output capacitor on the 750mA channel and a 3.3μF ceramic output capacitor on the 250mA channel. Internal protection circuitry includes reverse-battery, no reverse current flow from output to input, current limiting with foldback and thermal shutdown. The thermal shutdown circuitry protects both channels if an overload or fault condition occurs on either channel. Compact packages offer thermal resistances equivalent to much larger conventional packages. The device is available in the 20-lead thermally enhanced TSSOP and 28-lead 4mm x 5mm QFN packages. A wide variety of grades/temperature ranges are offered, including E and I grades -40°C to +125°C, H grade -40°C to +150°C and the high reliability MP grade -55°C to +150°C. 1,000-piece pricing starts at $3.27 for the E grade. For more information, visit www.linear.com/product/LT3030. Summary of Features: LT3030 Output Current: 750mA / 250mA Low Dropout Voltage: 300mV Low Noise: 20μVRMS (10Hz to 100kHz) Low Quiescent Current: 110μA/70μA Wide Input Voltage Range: 1.8V to 20V Adjustable Output Voltage: 1.215V to 19.5V Stable with 10μF/3.3μF Minimum Ceramic Output Capacitor Low Shutdown Current <1μA Reverse Battery Protection No Reverse Current Flow from Output to Input Thermal Shutdown & Current Limiting with Foldback Precision Threshold for Shutdown Logic or UVLO Function PWRGD Flag for Each Output Thermally Enhanced TSSOP-20E & 4mm x 5mm QFN-28 Packages Linear Technology