ADP7185ACPZN3.0-R7

Overview

The ADP7185ACPZN3.0-R7 is a negative-output low dropout linear regulator from Analog Devices, providing a fixed -3.0 V output with up to -500 mA load current capability. It operates within an input voltage range of -2.0 V to -5.5 V and features ultralow noise performance (4 μV rms) alongside high power supply rejection ratios reaching 68 dB at 10 kHz. The device incorporates positive or negative enable logic, thermal overload protection, and current limiting, packaged in an 8-lead, 2 mm × 2 mm LFCSP.

Feature Summary

• Ultralow noise architecture delivering 4 μV rms integrated output noise independent of the selected output voltage.
• High power supply rejection ratio (PSRR) maintaining effective filtering across frequencies up to 1 MHz under full load conditions.
• Flexible enable logic supporting both positive and negative control signals for system integration versatility.
• Robust protection mechanisms including current-limit thresholds and thermal shutdown to ensure operational safety.

Applications

• Power regulation for analog-to-digital converters (ADCs) requiring clean negative rails.
• Precision digital-to-analog converter (DAC) biasing applications.
• Negative supply generation for precision amplifiers in instrumentation systems.

Procurement Notes

Verify the specific ordering suffix matches the required package and tape-and-reel specifications. Confirm that the fixed -3.0 V output variant aligns with the design requirements, as other voltage options exist within the ADP7185 family. Ensure compatibility with the recommended 4.7 μF ceramic input and output capacitors for stable operation.

Selection Notes

Select this component when a stable negative voltage rail is required for sensitive analog circuits. The fixed -3.0 V option eliminates external feedback resistors, simplifying the design. Consider the -500 mA current capacity and ultralow noise profile for high-performance signal chain applications where power supply ripple must be minimized.

Part Context

This part belongs to the ADP7185 series of complementary metal oxide semiconductor (CMOS) low dropout linear regulators. The series is characterized by its ability to drive high currents while maintaining exceptional noise performance and line regulation. The specific model utilizes a proprietary architecture optimized for small ceramic capacitors, ensuring stability without the need for bulky components.

Replacement Considerations

Direct replacements include other ADP7185 variants with different fixed output voltages if the -3.0 V level is adjustable in the target circuit. Verify pinout compatibility and thermal resistance characteristics when substituting with similar negative LDO regulators from other manufacturers.