ADM7172ACPZ-3.3-R7

Overview

The ADM7172ACPZ-3.3-R7 is a fixed-output CMOS low dropout linear regulator (LDO) manufactured by Analog Devices Inc., providing a regulated 3.3 V output with a maximum load current of 2 A. It operates from an input voltage range of 2.3 V to 6.5 V and features ultralow noise performance, delivering 5 µV rms in the 100 Hz to 100 kHz bandwidth. The device achieves high power supply rejection ratio (PSRR) of 60 dB at 100 kHz and fast transient response, settling within 1.5 μs for a 1 mA to 1.5 A load step. It maintains stability using small 4.7 µF ceramic output capacitors and includes precision enable control with adjustable soft start functionality.

Feature Summary

• Ultralow noise architecture delivers consistent 5 µV rms output noise independent of the fixed output voltage setting.
• High power supply rejection ratio ensures effective attenuation of input supply ripple across critical frequency bands.
• Fast transient response capability allows rapid recovery from significant load current steps without external compensation.
• Precision enable pin provides programmable logic thresholds for reliable system power sequencing and shutdown.

Applications

• Regulation for noise-sensitive analog-to-digital converter (ADC) and digital-to-analog converter (DAC) circuits
• Powering precision amplifiers and phase-locked loops (PLLs) or voltage-controlled oscillators (VCOs)
• Clocking integrated circuits requiring stable low-noise voltage rails
• Medical and healthcare equipment demanding high reliability and low quiescent current

Procurement Notes

Verify the component authenticity through official Analog Devices channels or authorized distributors. Confirm the package marking matches the 8-lead LFCSP specification. Ensure the ordering suffix corresponds to the reel packaging format required for surface-mount assembly processes. Cross-reference the date code against current production status to guarantee availability.

Selection Notes

Select this model when a fixed 3.3 V rail is required for high-performance mixed-signal applications. The device is suitable for designs needing minimal output capacitance while maintaining stability under heavy dynamic loads. Consider the thermal dissipation capabilities of the exposed pad design for high-current scenarios. Verify that the input voltage headroom meets the minimum dropout requirements for the intended operating conditions.

Part Context

This component belongs to the ADM7172 family of high-current, ultralow noise LDOs designed for portable and battery-powered systems. It shares architectural similarities with the ADM7170 and ADM7171 but offers higher current capacity. The series supports various fixed and adjustable output voltages within the same compact footprint, facilitating standardized board layouts across different product variants.

Replacement Considerations

Direct functional substitutes include other ADM7172 variants with different fixed output voltages if the voltage level can be adjusted externally. The ADM7171 serves as a lower-current alternative within the same package family. Verify pin compatibility and thermal characteristics before substituting with non-Analog Devices LDOs offering similar specifications.