LT3042屬于集成電路（IC）的線性+開關(guān)穩(wěn)壓器。由亞德諾半導(dǎo)體技術(shù)有限公司制造生產(chǎn)的LT3042穩(wěn)壓器 - 線性線性穩(wěn)壓器用于提供穩(wěn)定的輸出電壓，無論負載電流、輸入電壓或環(huán)境因素如何變化，這些輸出電壓通常都要保持不變。它們的工作原理要求輸入電壓維持在高于所需的輸出電壓，而且要超出某個最小量，并且在工作時會將輸入端的任何多余電壓轉(zhuǎn)換為熱量。對于大多數(shù)應(yīng)用而言，雖然這種穩(wěn)壓器的效率低于開關(guān)模式的穩(wěn)壓器，但它們通常更適合對噪聲高度敏感的應(yīng)用。

GENERAL DESCRIPTION

The LT?3073 is a low voltage, ultra-low noise, and

ultra-fast transient response linear regulator. The

device supplies up to 3A with a typical dropout

voltage of 45mV. A 4.7μF reference bypass capacitor

decreases output voltage noise to 1.2μVRMS. The wide

bandwidth and high PSRR permit the use of small

ceramic capacitors, saving bulk capacitance and cost.

The LT3073 is ideal for powering high-performance

FPGAs, data converters, RF, and noise-sensitive signal

chain applications.

The output voltage is digitally selectable in 50mV

increments from 0.5V to 1.2V, 100mV increments from

1.2V to 1.8V, and discrete levels at 2V, 2.5V, 3V, 3.3V,

and 4.2V. The LT3073’s unity-gain operation provides

virtually constant output noise, PSRR, bandwidth,

and load regulation independent of the programmed

output voltage. In addition, the LT3073 incorporates

a unique tracking feature (VIOC) to control the

upstream switching regulator to maintain a constant

voltage across the LT3073 and minimize power

dissipation.

A precision current monitor provides power

monitoring for system energy management, while

precision current limiting allows users to minimize

input power supply size and cost. Built-in protection

includes UVLO, internal current limit, and thermal

shutdown with hysteresis. The LT3073 is available in

a compact 22-lead (3mm X 4mm) LQFN package

(Laminate package with QFN footprint).

FEATURES

? Ultra-low RMS Noise: 1.2μVRMS (10Hz to 100kHz)

? Ultra-low Spot Noise: 3nV/√ at 10kHz

? Ultra-low 1/f Noise: 7μVP-P from 0.1Hz to 10Hz

? High-Frequency PSRR: 52dB at 1MHz

? Ultra-fast Transient Response

? Dropout Voltage: 45mV Typical

? Digitally Programmable VOUT: 0.5V to 4.2V

? Output Tolerance: ±1.5 Over Line, Load, and

Temperature

? Precision Current Monitor: ±3 accuracy at 3A

? Programmable Current Limit: ±3 at 3A

? Input Range: 0.6V to 5.5V

? Digital Output Margining: ±2.5

? Stable with Ceramic Output Capacitors (10μF

Minimum)

? Parallel Multiple Devices for Higher Current

? VIOC Pin to Control Upstream Switching Converter

? Precision Enable/Under Voltage Lock Out (UVLO)

? Power Good (PG) Flag

? Temperature Monitor

? 22-Lead (3mm x 4mm) LQFN Package

APPLICATIONS

? RF Power Supplies: PLLs, VCOs, Mixers, LNAs, PAs

? High Speed/High Precision Data Converters

? Low Noise Instrumentation

? Post-Regulator for Switching Supplies

? FPGA and DSP Power Supplies

? Medical Applications