ADM7170ACPZ-3.3-R7

Overview

The ADM7170ACPZ-3.3-R7 is a fixed-output low dropout linear regulator providing a regulated 3.3 V output with a maximum load current of 500 mA. 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 of 1.5 μs for a 1 mA to 500 mA load step. Initial accuracy is ±0.75%, dropping to ±1.25% over line, load, and temperature conditions. Quiescent current is 0.7 mA at no load, reducing to 0.25 μA during shutdown. It requires only a 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 settles within 1.5 μs following rapid load steps up to 500 mA using minimal external capacitance.
• Precision enable pin provides precise logic thresholds for reliable system control and sequencing.

Applications

• Noise-sensitive analog circuits such as ADC and DAC regulation
• Precision amplifier power supplies
• PLL/VCO and clocking IC biasing
• Communications and infrastructure equipment
• Medical and healthcare instrumentation

Procurement Notes

Verify the specific suffix R7 indicates tape and reel packaging when ordering. Confirm the ACPZ designation corresponds to the 8-lead LFCSP package variant. Ensure compatibility with the required 3.3 V fixed output specification. Check for RoHS compliance status relevant to your manufacturing region. Validate that the supplier documentation matches the Analog Devices datasheet revision D specifications.

Selection Notes

Select this component when ultralow noise and high PSRR are critical for sensitive analog loads. The fixed 3.3 V output eliminates the need for external feedback resistors, simplifying board layout. Ensure the input voltage remains above 2.3 V and within the 6.5 V maximum limit. Verify thermal dissipation requirements based on the junction-to-ambient resistance of the LFCSP package under expected load conditions.

Part Context

This part belongs to the ADM7170 family of CMOS low dropout linear regulators designed for high-performance mixed-signal applications. The series offers various output currents and voltage options, including adjustable versions. The ADM7170 specifically targets portable and battery-powered devices requiring efficient regulation with minimal quiescent current consumption while maintaining strict noise specifications.

Replacement Considerations

The ADM7171ACPZ-3.3-R7 serves as a higher current alternative within the same family, offering 1 A output capability in a similar package. Designers requiring increased load capacity should verify thermal performance and PCB layout adjustments necessary for the higher current rating.