POWER AND LINEAR IC SOLUTIONS

High Power-Density LDO Device

Traditionally, engineers use switching regulator devices to power high-performance digital ICs but noise and layout limitations are increasingly emerging. As a result, Low DropOut (LDO) linear regulators have become the optimal method for achieving the best results.

The LT3070 from Linear Technology is a 5A, low noise, programmable output LDO for use with digital ICs including FPGAs, DSPs, microcontrollers, microprocessors and ASICs. Its MOS-based architecture allows for a dropout of only 85mV at full load with no variation in ground-pin current as input or output voltage changes. The output voltage noise is only 25µV_RMS across a wide bandwidth of 10Hz to 100kHz. The Power Supply Rejection Ratio (PSRR) is 35dB at 1MHz.



Accuracy is tightly specified at ±1% over line, load and temperature. A digital ‘margining’ feature gives system output-voltage tolerance in increments of ±1%, ±3% or ±5%, advantageous during system development debug. Its 1MHz gain bandwidth and its minimum 15µF ceramic output capacitance minimises overshoot/undershoot and significantly saves bulk capacitance, space and cost.

Multiple LT3070 devices may be paralleled for higher output current and to spread heat across the PCB. A tracking feature can control a buck regulator powering the LT3070’s input. Internal protection circuitry includes UnderVoltage LockOut (UVLO); reverse-current protection; precision current limiting with power foldback; thermal shutdown with hysteresis.

Offered in a low profile (0.75mm), 28-lead QFN package (with a 4mm x 5mm footprint), the input supply voltage range is 0.95V to 3.0V and bias supply voltage ranges from 2.2V to 3.6V. The output voltage is digitally programmable from 0.8V to 1.8V in 50mV increments.

Features

• 5A output current
• 85mV dropout voltage (typical)
• Digitally programmable Vout: 0.8V to 1.8V
• Low output noise: 25μV_RMS (10Hz to 100kHz)
• High frequency PSRR: 30dB at 1MHz

Applications

• FPGA, DSP, ASIC and microprocessor power supplies
• Servers and storage devices
• Post-buck regulation and supply isolation

For further information, to register your interest in a Free Demo Board*, or to obtain a copy of the latest Altera/LTC Development Tools Brochure or LT3070 Datasheet, please click here

* Free demo boards are limited to current or potential Arrow customers with valid opportunities and are at the discretion of local Arrow representatives.