5A, Low Noise, Programmable Output, 85mV Dropout Linear Regulator with Analog Margining

The LT3071 is a low voltage, UltraFast™ transient response linear regulator. The device supplies up to 5A of output current with a typical dropout voltage of 85mV. A 0.01μF reference bypass capacitor decreases output voltage noise to 25μVRMS. The LT3071’s high bandwidth permits the use of low ESR ceramic capacitors, saving bulk capacitance and cost. The LT3071’s features make it ideal for high performance FPGAs, microprocessors or sensitive communication supply applications.

Output voltage is digitally selectable in 50mV increments over a 0.8V to 1.8V range. An analog margining function allows the user to adjust system output voltage over a continuous ±10% range. The IC incorporates a unique tracking function to control a buck regulator powering the LT3071’s input. This tracking function drives the buck regulator to maintain the LT3071’s input voltage to VOUT + 300mV, minimizing power dissipation.

Internal protection includes UVLO, reverse-current protection, precision current limiting with power foldback and thermal shutdown. The LT3071 regulator is available in a thermally enhanced 28-lead, 4mm × 5mm QFN package.

APPLICATIONS

* FPGA and DSP Supplies

* ASIC and Microprocessor Supplies

* Servers and Storage Devices

* Post Buck Regulation and Supply Isolation

* Output Current: 5A

* Dropout Voltage: 85mV Typical

* Digitally Programmable VOUT : 0.8V to 1.8V

* Analog Output Margining: ±10% Range

* Low Output Noise: 25μVRMS (10Hz to 100kHz)

* Parallel Multiple Devices for 10A or More

* Precision Current Limit: ±20%

* Output Current Monitor: IMON = IOUT/2500

* ±1% Accuracy Over Line, Load and Temperature

* High Frequency PSRR: 30dB at 1MHz