**ADP7142ARDZ-5-R7: A Comprehensive Technical Overview of the 5V, 500mA Low-Noise LDO Regulator**

In the realm of power management, achieving a clean, stable, and low-noise voltage supply is paramount for the performance of sensitive analog and RF circuits. The **ADP7142ARDZ-5-R7** from Analog Devices stands out as a premier solution, engineered specifically to meet these demanding requirements. This article provides a detailed technical examination of this high-performance, 5V, 500mA low-dropout (LDO) linear regulator.

The ADP7142 is a CMOS LDO regulator featuring a **5 V fixed output voltage** and a substantial **maximum output current of 500 mA**. Its core strength lies in its exceptionally low-noise performance. The integrated **silicon-based band gap reference** is a key contributor, enabling an ultra-low output noise level of just **9 μV rms** (typical) across a 10 Hz to 100 kHz bandwidth. This makes it an ideal power source for noise-sensitive applications such as precision analog-to-digital converters (ADCs), digital-to-analog converters (DACs), voltage-controlled oscillators (VCOs), and imaging sensors, where noise on the supply rail can directly degrade system performance.

Beyond its low-noise characteristics, the ADP7142 boasts an outstanding **power supply rejection ratio (PSRR)**. It maintains a high PSRR of **70 dB at 10 kHz**, effectively filtering out unwanted ripple and noise from the preceding switching regulator or power stage. This ensures that disturbances on the input supply do not propagate to the critical load.

The device operates with a very low **dropout voltage of only 185 mV** at 500 mA load, allowing it to continue regulating effectively even when the input voltage dips close to the output level. This enhances power efficiency and provides greater design flexibility in managing input voltage variations. The ADP7142ARDZ-5-R7 is offered in a compact, 8-lead **3 mm × 3 mm LFCSP package**, which offers excellent thermal performance for its power density and is suitable for space-constrained PCB designs.

A critical feature for system reliability is its robust set of **protection circuitry**, including internal current limiting and thermal overload protection. These safeguards shut down the regulator in the event of a fault condition, protecting both the device itself and the downstream components.

**ICGOO FIND**: The ADP7142ARDZ-5-R7 is a superior choice for designers who need a high-current, ultra-low-noise power solution. Its combination of **exceptional noise performance, high PSRR, and low dropout voltage** in a miniature package makes it an indispensable component for powering the most sensitive circuits in communications infrastructure, medical instrumentation, and test and measurement equipment.

**Keywords**: Low-Noise LDO Regulator, Power Supply Rejection Ratio (PSRR), 500mA Output Current, Ultra-Low Dropout Voltage, ADP7142.