ADM7172ACPZ-5.0-R7

Overview

The ADM7172ACPZ-5.0-R7 is a fixed-output CMOS low dropout linear regulator (LDO) manufactured by Analog Devices Inc., providing a regulated 5.0 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. Initial accuracy is specified between −0.5% and +1%, with line and load regulation ensuring ±1.5% accuracy over temperature. It utilizes a small 4.7 µF ceramic output capacitor and includes precision enable and adjustable soft start controls.

Feature Summary

• Ultralow noise architecture delivers consistent 5 µV rms output noise independent of the fixed output voltage setting.
• High power supply rejection ratio maintains 60 dB attenuation at 100 kHz to suppress input supply ripple effectively.
• Fast transient response capability settles output voltage deviations within 1.5 μs during significant load current steps.
• Precision enable pin provides precise logic threshold control for regulator activation and shutdown states.

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 power rails
• Medical and healthcare equipment requiring reliable linear regulation

Procurement Notes

Verify the specific ordering suffix R7 corresponds to tape and reel packaging when sourcing components. Confirm that the fixed 5.0 V output variant matches the system requirement, as the ADM7172 family offers adjustable and other fixed voltage options. Ensure the 8-lead LFCSP package dimensions align with the printed circuit board layout constraints. Check for RoHS compliance status and moisture sensitivity level requirements before finalizing procurement specifications.

Selection Notes

Select this component when applications demand high current delivery up to 2 A combined with stringent noise suppression requirements. The fixed 5.0 V output eliminates the need for external feedback resistors, simplifying design complexity compared to adjustable variants. Consider the thermal resistance characteristics of the 3 mm × 3 mm LFCSP package for heat dissipation planning under full load conditions. Verify that the input voltage headroom remains sufficient to maintain operation above the dropout voltage threshold across all operating temperatures.

Part Context

The ADM7172 belongs to a family of CMOS low dropout regulators designed for high-performance analog and mixed-signal applications. It shares architectural similarities with the ADM7170 and ADM7171 but distinguishes itself through higher current capacity and optimized transient response. The device integrates protection features including current limiting and thermal overload shutdown. Its design targets portable equipment and infrastructure systems where space efficiency and power integrity are critical.

Replacement Considerations

The ADM7171ACPZ-5.0-R7 serves as a lower-current alternative within the same package, offering 1 A output instead of 2 A. Designers must verify that the reduced current capability meets the application's peak load demands. Other fixed voltage options within the ADM7172 series may replace this unit if different output levels are required, provided the pinout and thermal characteristics remain compatible.