Analog Devices Inc. ADP2125BCDZ-1.26R7

Overview

ADP2125BCDZ-1.26R7 from Analog Devices is a synchronous step-down DC-to-DC converter optimized for space-constrained portable systems. It delivers 500 mA continuous output at a fixed 1.26 V, operates from 2.1 V to 5.5 V input, supports 6 MHz switching, and features external clock enable (6–27 MHz) for precise power sequencing in camera modules and digital audio subsystems.

For engineers reviewing the ADP2125BCDZ-1.26R7 datasheet, ADP2125BCDZ-1.26R7 pinout, ADP2125BCDZ-1.26R7 application, or ADP2125BCDZ-1.26R7 equivalent, key selection criteria include fixed-output voltage accuracy (±2%), ultralow shutdown current (0.3 μA typ), internal soft start, output short-circuit protection, and compatibility with 0603-size multilayer ceramic capacitors and chip inductors.

Technical Context

The ADP2125BCDZ-1.26R7 uses a hybrid voltage-mode PWM control architecture that maintains constant 6 MHz switching frequency across all load conditions, ensuring stable loop dynamics and fast transient response. Its internal synchronous rectifier integrates both P-channel (180–340 mΩ) and N-channel (250 mΩ) MOSFETs to eliminate external diode losses.

Operation is gated by an external 6–27 MHz clock applied to the EXTCLK pin; absence of clock signal disables the converter and reduces supply current to 0.3 μA typical. Protection includes cycle-by-cycle peak current limiting (770–1291 mA), undervoltage lockout (1.9 V rising threshold), thermal shutdown (146°C), and output-to-ground short-circuit detection (0.55 V falling threshold).

Key Specifications

Pinout & Package

ADP2125BCDZ-1.26R7 is housed in a 6-ball bumped bare die package (BUMPED_CHIP), measuring 1.6 mm × 0.8 mm × 0.405 mm max height. The package uses solder bumps on the bottom side; top-side ball indicators align with standard flip-chip mounting orientation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS62231DRYR and MAX17222ETA+T, ADP2125BCDZ-1.26R7 uniquely combines precise 1.26 V output, 6 MHz operation for smallest passive components, and EXTCLK-based power sequencing - making it optimal for camera and audio subsystems where voltage accuracy, size, and timing control are jointly critical.

Availability

ADP2125BCDZ-1.26R7 is available at Aetrix Electronics and suitable for mobile phone power rails, digital camera image sensors, portable audio codecs, and camera module stabilization systems requiring stable component supply, long-term lifecycle support, and consistent parametric performance across production batches.

Supply support for ADP2125BCDZ-1.26R7 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 since 1965.

The ADP2125BCDZ-1.26R7 belongs to Analog Devices' ADP21xx family of high-frequency synchronous buck converters, designed specifically for battery-powered portable electronics where minimal solution size, low quiescent current, and robust protection are mandatory.

FAQ

What is the output voltage tolerance of the ADP2125BCDZ-1.26R7 over temperature and line variations?

The ADP2125BCDZ-1.26R7 provides a fixed 1.26 V output with ±2% accuracy over input voltage range 2.3 V to 4.8 V and temperature range −40°C to +85°C. This specification excludes transient events and is guaranteed by design - no external trimming or calibration is required. The ADP2125BCDZ-1.26R7 achieves this stability through internal precision bandgap reference and factory-trimmed feedback network.

Does the ADP2125BCDZ-1.26R7 require external compensation components?

No, the ADP2125BCDZ-1.26R7 features internal compensation, eliminating the need for external RC networks or type-II/type-III compensators. This simplifies design, reduces bill-of-materials cost, and ensures stable operation with recommended 1.5 µH inductors and 4.7 µF output capacitors. The ADP2125BCDZ-1.26R7's internal loop is optimized for ceramic output capacitors with ESR <10 mΩ.

Can the ADP2125BCDZ-1.26R7 operate without an external clock signal?

No - the ADP2125BCDZ-1.26R7 requires a 6–27 MHz clock signal applied to the EXTCLK pin to initiate and sustain operation. When EXTCLK is held low (≤0.5 V), the device enters shutdown mode drawing only 0.3 µA. The ADP2125BCDZ-1.26R7 does not support internal oscillator fallback; absence of clock disables power delivery entirely.

What is the maximum allowable inductor DCR for stable operation of the ADP2125BCDZ-1.26R7 at full load?

For stable operation at 500 mA continuous output, the inductor DCR should not exceed 350 mΩ (typical value for Murata LQM18PN1R5NB0L). Higher DCR increases conduction loss and junction temperature - the ADP2125BCDZ-1.26R7's thermal shutdown triggers at 146°C. At 500 mA, inductor DCR >500 mΩ risks exceeding safe operating temperature under worst-case ambient conditions.

How does the ADP2125BCDZ-1.26R7 handle output short-circuit faults?

Upon detecting output voltage below 0.55 V (rising threshold), the ADP2125BCDZ-1.26R7 immediately disables switching and enters auto-retry mode: it remains off for ~450 µs, then initiates soft start. This cycle repeats until the short is removed or EXTCLK is disabled. During fault, average power delivered is limited to <10 mW - protecting the ADP2125BCDZ-1.26R7, inductor, and PCB traces.