Analog Devices Inc. ADP2118ACPZ-2.5-R7

Overview

ADP2118ACPZ-2.5-R7 from Analog Devices is a synchronous step-down DC-DC regulator delivering up to 3 A continuous output current, operating from 2.3 V to 5.5 V input, with fixed 2.5 V output, ±1.5% accuracy, and selectable 600 kHz or 1.2 MHz switching frequency. It integrates 75 mΩ high-side and 40 mΩ low-side MOSFETs and supports voltage tracking for FPGA core/I/O sequencing in compact point-of-load applications.

For engineers reviewing the ADP2118ACPZ-2.5-R7 datasheet, ADP2118ACPZ-2.5-R7 pinout, ADP2118ACPZ-2.5-R7 application, or ADP2118ACPZ-2.5-R7 equivalent, key selection considerations include its 16-lead 4 mm × 4 mm LFCSP package, PFM/PWM mode selectability, precision enable threshold (1.2 V typ), power-good output, and precharged-output startup capability.

Technical Context

The ADP2118ACPZ-2.5-R7 uses a current-mode, constant-frequency PWM control architecture with integrated slope compensation for stability at duty cycles >50%. Its dual-mode operation-fixed-frequency PWM under medium-to-full load and variable-frequency PFM at light loads-enables high efficiency across 0–3 A output range.

It features a precision 0.6 V internal feedback reference, synchronized switching capability (600 kHz–1.4 MHz), selectable 0°/180° phase shift, and integrated protection including UVLO (2.2 V rising), OVP (0.66 V FB threshold), OCP (5.2 A peak), and thermal shutdown (140°C).

Key Specifications

Pinout & Package

ADP2118ACPZ-2.5-R7 is housed in a 16-lead, 4 mm × 4 mm LFCSP package with exposed thermal pad soldered to PCB ground plane for optimal thermal dissipation (θ_JA = 38.3°C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar step-down regulator applications.

Compared with TPS62130ARGTR and RT6220AGQW, ADP2118ACPZ-2.5-R7 uniquely combines fixed 2.5 V output, voltage tracking, synchronization, and auto-PFM in a thermally enhanced LFCSP - making it optimal for sequenced, low-noise, and battery-sensitive applications where reliability and feature integration are prioritized over minimal BOM count.

Availability

ADP2118ACPZ-2.5-R7 is available at Aetrix Electronics and suitable for FPGA power sequencing, industrial sensor nodes, medical imaging modules, and automotive infotainment SoC designs requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for ADP2118ACPZ-2.5-R7 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving precision instrumentation, communications, industrial, and automotive markets.

The ADP2118 product line delivers highly integrated, thermally efficient synchronous buck regulators targeting space-constrained, multi-rail point-of-load applications demanding sequencing, low IQ, and robust protection.

FAQ

What is the output voltage tolerance of the ADP2118ACPZ-2.5-R7?

The ADP2118ACPZ-2.5-R7 has a guaranteed output voltage tolerance of ±1.5% over temperature (−40°C to +125°C) and line/load conditions. This specification is confirmed in Table 1 of the Rev. E datasheet under "FB Regulation Voltage", where V_FB = 0.591 V to 0.609 V - directly corresponding to the 2.5 V fixed output with internal resistor divider scaling. The ADP2118ACPZ-2.5-R7 achieves this accuracy without external calibration or trimming components.

Does the ADP2118ACPZ-2.5-R7 support startup into a precharged output?

Yes, the ADP2118ACPZ-2.5-R7 explicitly supports startup into a precharged output. As stated in the General Description and Theory of Operation sections, it prevents reverse inductor current by holding both FETs off until the soft-start voltage exceeds the FB pin voltage. This behavior is verified in Figure 25 ("Soft Start with Precharge") and ensures safe operation when the output capacitor is already biased - a critical requirement in hot-swap and redundant power systems using ADP2118ACPZ-2.5-R7.

How is the switching frequency selected on the ADP2118ACPZ-2.5-R7?

The switching frequency of the ADP2118ACPZ-2.5-R7 is selected via the FREQ pin: connecting FREQ to GND sets 600 kHz, and connecting FREQ to VIN selects 1.2 MHz. This is a hardware-configured, non-volatile setting - no register writes or external clocks required. The datasheet confirms this in Table 4 (Pin Function Descriptions) and Figure 16/19 (frequency vs. VIN curves), where measured frequencies remain stable across temperature and input voltage for each configuration.

What protection features are integrated into the ADP2118ACPZ-2.5-R7?

The ADP2118ACPZ-2.5-R7 integrates undervoltage lockout (UVLO), overvoltage protection (OVP), overcurrent protection (OCP), thermal shutdown (TSD), and hiccup-mode fault recovery. UVLO activates below 2.1 V (falling), OVP triggers when FB exceeds 0.66 V for 16 clock cycles, OCP limits peak switch current to 5.2 A, and TSD engages at 140°C with 15°C hysteresis. All protections are detailed in the Theory of Operation section and validated in functional test waveforms (Figures 28, 31, and 32) - ensuring robust operation of ADP2118ACPZ-2.5-R7 in real-world fault scenarios.

Can the ADP2118ACPZ-2.5-R7 be synchronized to an external clock?

Yes, the ADP2118ACPZ-2.25-R7 - wait, correction: the ADP2118ACPZ-2.5-R7 supports external synchronization via its SYNC/MODE pin, accepting input clocks from 600 kHz to 1.4 MHz. When synchronized, it operates only in CCM mode, and phase alignment (0° or 180°) is determined by the FREQ pin state. This capability is documented in the Oscillator and Synchronization section and demonstrated in Figures 24 and 27 (in-phase and 180° out-of-phase waveforms), confirming deterministic timing control for ADP2118ACPZ-2.5-R7 in noise-sensitive or multi-regulator systems.