**ADP7158ACPZ-8-R7: A Comprehensive Technical Overview and Application Guide**

The **ADP7158ACPZ-8-R7** from Analog Devices is a high-performance, low-noise, low-dropout (LDO) linear voltage regulator designed to meet the stringent power requirements of modern RF, analog, and mixed-signal systems. This device stands out for its exceptional noise performance and high power supply rejection ratio (PSRR), making it an ideal choice for powering noise-sensitive components such as **phase-locked loops (PLLs), voltage-controlled oscillators (VCOs), and high-resolution analog-to-digital converters (ADCs)**.

**Key Technical Specifications and Features**

The ADP7158 is an adjustable regulator, with the `-8` suffix in the part number denoting its preset output voltage of 0.8 V. The device accepts an input voltage range from **2.3 V to 5.5 V** and can deliver a robust maximum output current of **1.5 A** with a typical dropout voltage of only 125 mV. Its core strengths lie in its ability to provide a clean, stable output voltage.

* **Ultra-Low Noise Performance:** The ADP7158 incorporates an innovative architecture that achieves an ultra-low output noise level of **0.48 μV√Hz** at 10 kHz. This is critical for applications where switching noise from other power supplies can degrade signal integrity and overall system performance.

* **Excellent Power Supply Rejection Ratio (PSRR):** It offers an outstanding PSRR of **80 dB at 10 kHz**, effectively attenuating ripple and noise from upstream switching regulators (SMPS). This allows designers to use a noisy but efficient switcher for bulk conversion, followed by the ADP7158 as a "clean-up" LDO for sensitive load circuits.

* **High Accuracy and Stability:** The regulator provides a high output voltage accuracy of **±1.2%** over line, load, and temperature conditions. It is stable with a small, space-saving 1 μF ceramic output capacitor, simplifying board design and reducing the bill of materials (BOM).

* **Advanced Protection and Control:** The device includes essential protection features such as **current limiting and thermal shutdown**. It also features an enable (EN) pin for power sequencing and to put the device into a low quiescent current shutdown mode when not in use, conserving power in battery-operated applications.

**Package and Part Number Decoding**

The part number `ADP7158ACPZ-8-R7` provides specific information:

* **ADP7158:** Base product number.

* **A:** Denotes the specific silicon revision.

* **CPZ:** Indicates the package type, a compact 4 mm x 4 mm, 10-lead LFCSP (Lead Frame Chip Scale Package).

* **-8:** Signifies the factory-set output voltage of 0.8V.

* **R7:** Represents the tape and reel packaging for high-volume assembly.

**Typical Application Circuit**

Implementing the ADP7158 is straightforward. The basic application circuit requires only three external components: an input capacitor (CIN), an output capacitor (COUT), and two feedback resistors (R1 and R2) for adjustable voltage versions. For the fixed `-8` version, the internal feedback network is pre-set, further simplifying the design. The input and output capacitors should be placed as close as possible to the regulator's pins to minimize parasitic inductance and ensure stability. The high PSRR and low noise are inherent to the IC's design and do not require additional filtering components in most cases.

**Primary Application Areas**

The combination of low noise, high PSRR, and 1.5A current capability makes the ADP7158ACPZ-8-R7 exceptionally versatile. Its primary applications include:

* **Communicication Infrastructure:** Powering RF transceivers, baseband processors, and data converters in 4G/5G base stations and microwave backhaul systems.

* **Test and Measurement Equipment:** Providing clean power to high-precision sensors, data acquisition systems, and spectrum analyzers.

* **Medical Imaging and Diagnostics:** Used in MRI, CT scanners, and ultrasound machines where signal clarity is paramount.

* **Industrial and Instrumentation:** Supporting sensitive analog front-ends and control systems in automated test equipment (ATE) and factory automation.

**ICGOODFIND**

The ADP7158ACPZ-8-R7 is a premier LDO regulator that sets a benchmark for **low noise and high PSRR performance** in a high-current package. Its ability to efficiently filter noisy power rails and deliver pristine DC power makes it an indispensable component for engineers designing advanced systems where signal integrity cannot be compromised. Its simple implementation and robust feature set streamline the design process, reducing time to market for a wide range of demanding applications.

**Keywords:**

1. **Low-Dropout (LDO) Regulator**

2. **Ultra-Low Noise**

3. **High PSRR (Power Supply Rejection Ratio)**

4. **RF/Analog Power Management**

5. **1.5A Output Current**