Analog Devices Inc. ADP1872ARMZ-0.3-R7

Overview

ADP1872ARMZ-0.3-R7 from Analog Devices is a synchronous current-mode PWM buck controller with constant on-time architecture, designed for high-efficiency DC/DC conversion in space-constrained power supplies. It operates from 2.75 V to 20 V input, delivers output as low as 0.6 V with ±1.0% reference accuracy, supports all-N-channel MOSFET stages, and features integrated bootstrap diode and valley current-mode control for optimal transient response at low duty cycles - used in DSP core power supplies and telecom systems.

For engineers reviewing the ADP1872ARMZ-0.3-R7 datasheet, ADP1872ARMZ-0.3-R7 pinout, ADP1872ARMZ-0.3-R7 application, or ADP1872ARMZ-0.3-R7 equivalent, key selection criteria include its 300 kHz switching frequency, 10-lead MSOP package, resistor-programmable current-sense gain, PSM exclusion (ADP1872 variant), and thermal shutdown at 155°C - critical for server VRM and set-top box power design.

Technical Context

The ADP1872ARMZ-0.3-R7 implements a pseudo-fixed-frequency, constant on-time control scheme with valley current sensing to maintain stability across wide VIN/VOUT ratios. Its architecture enables precise regulation down to 0.6 V while supporting high-side N-MOSFET drive via integrated bootstrap rectifier and low-side current-sense amplification with programmable gain (2.7–26 V/V).

It uses a precision enable threshold (235–330 mV) with 35 mV hysteresis, soft-start period of 3.0 ms, and undervoltage lockout (2.65 V rising) to ensure controlled startup into precharged loads. Thermal shutdown (155°C) and hiccup-mode short-circuit protection provide robust fault handling without external circuitry.

Key Specifications

Pinout & Package

ADP1872ARMZ-0.3-R7 is housed in a 10-lead MSOP package with exposed pad for thermal enhancement. Pin assignments are validated per Analog Devices Rev. B datasheet Figure 3 and Table 4.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous buck controller applications.

Compared with ADP1873ARMZ-0.3-R7, the ADP1872ARMZ-0.3-R7 omits PSM for deterministic PWM operation - critical for EMI-sensitive telecom systems. Versus TPS54332DR, it offers superior low-VOUT accuracy, integrated bootstrap, and smaller MSOP footprint but requires more careful loop compensation.

Availability

ADP1872ARMZ-0.3-R7 is available at Aetrix Electronics and suitable for telecom power supplies, DSP core regulators, mid-range server VRMs, and set-top box SoC power requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for ADP1872ARMZ-0.3-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 industrial, automotive, communications, and healthcare markets.

The ADP1872/ADP1873 product line delivers high-efficiency, flexible synchronous buck controllers for demanding point-of-load applications - specifically engineered for telecom infrastructure, server power, and multimedia SoC power domains.

FAQ

What is the switching frequency of the ADP1872ARMZ-0.3-R7?

The ADP1872ARMZ-0.3-R7 is factory-configured for a nominal switching frequency of 300 kHz, with typical variation of ±10% across temperature and load. This frequency is fixed by internal oscillator design and does not require external timing components - simplifying design for mid-power applications such as DSP core supplies where EMI and inductor size must be balanced.

Does the ADP1872ARMZ-0.3-R7 support power saving mode (PSM)?

No, the ADP1872ARMZ-0.3-R7 does not include power saving mode. PSM is exclusive to the ADP1873 variant (e.g., ADP1873ARMZ-0.3-R7). The ADP1872ARMZ-0.3-R7 operates in forced continuous conduction mode (CCM) at all load levels, ensuring constant switching frequency - beneficial for EMI filtering predictability and avoiding audible noise in sensitive applications.

What is the minimum output voltage supported by the ADP1872ARMZ-0.3-R7?

The ADP1872ARMZ-0.3-R7 supports a minimum regulated output voltage of 0.6 V, set by its internal reference with ±1.0% accuracy over −40°C to +125°C. This enables direct regulation for advanced processor cores and low-voltage FPGAs without external reference scaling, and is maintained via valley current-mode control that remains stable even at sub-10% duty cycles.

How is current sensing implemented in the ADP1872ARMZ-0.3-R7?

The ADP1872ARMZ-0.3-R7 implements low-side MOSFET R_DS(on)-based current sensing, eliminating the need for a discrete current-sense resistor. Gain is set by a resistor (RES) connected from DRVL to PGND, offering programmable values of 2.7–26 V/V depending on RES value (e.g., 47 kΩ yields 3 V/V). This approach reduces power loss and board area while preserving measurement accuracy across temperature.

What package type and thermal characteristics apply to the ADP1872ARMZ-0.3-R7?

The ADP1872ARMZ-0.3-R7 uses a 10-lead MSOP package with exposed pad, achieving θ_JA of 171.7°C/W on a 4-layer PCB. It incorporates thermal shutdown at 155°C with 15°C hysteresis and is rated for −40°C to +125°C junction operation. The exposed pad must be soldered to a thermal pad for optimal heat dissipation in high-current applications like server VRMs.