Analog Devices Inc. ADP2291ACPZ-R7

Overview

ADP2291ACPZ-R7 from Analog Devices is a constant-current/constant-voltage linear lithium-ion battery charger IC for single-cell systems, supporting 4.5 V to 12 V input, delivering up to 1.5 A charge current, featuring ±1% 4.2 V output voltage accuracy over line and temperature, automatic precharge for deeply discharged cells (<2.85 V), and thermal shutdown at 135°C. It is used in compact portable electronics requiring safe, low-component-count charging.

For engineers reviewing the ADP2291ACPZ-R7 datasheet, ADP2291ACPZ-R7 pinout, ADP2291ACPZ-R7 application, or ADP2291ACPZ-R7 equivalent, key selection considerations include external PNP pass transistor drive capability (40 mA max base current), programmable charge current via ADJ pin (50–150 mV sense voltage range), timer capacitor-based timeout control, reverse isolation without external diode, and LFCSP-8 package thermal performance (θ_JA = 48°C/W on 4-layer board).

Technical Context

The ADP2291ACPZ-R7 implements a multistep charging algorithm-precharge (trickle at ~10–20 mV sense), fast charge (adjustable up to 1.5 A via RS and ADJ), and end-of-charge (voltage-regulated at 4.2 V ±1%)-with automatic recharge triggered by >100 mV battery voltage drop. Its internal control logic monitors VIN relative to BAT (VIN good comparator threshold: 125–220 mV above VBAT) and disables charging if input falls below 3.8 V.

Safety is enforced through integrated functions: overshoot protection (activates at 4.7–5.3 V on BAT, sinks up to 1.5 A), thermal shutdown (135°C trip, 35°C hysteresis), battery fault detection (precharge timeout, no voltage rise), and automatic reverse isolation (DRV drives PNP base to BAT when VIN < BAT). The CHG open-collector output provides real-time charge status indication.

Key Specifications

Pinout & Package

ADP2291ACPZ-R7 is housed in a 3 mm × 3 mm, 8-lead LFCSP package with exposed pad for thermal enhancement. Pin 1 is marked with dot; pin numbering follows standard counter-clockwise orientation from top-left corner.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar linear lithium-ion battery charger applications.

Compared with TPS65023BRSBT and BQ24075RGTR, ADP2291ACPZ-R7 uniquely supports 1.5 A via external PNP with full ADJ-based current scaling (50–150 mV), true reverse isolation without diode, and superior thermal performance in LFCSP, making it optimal for high-current, thermally constrained, or battery-health-critical designs.

Availability

ADP2291ACPZ-R7 is available at Aetrix Electronics and suitable for wireless handsets, smart handhelds, and digital cameras requiring stable component supply, long-term lifecycle support, and consistent parametric performance across production batches.

Supply support for ADP2291ACPZ-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, industrial automation, communications, and automotive markets.

The ADP2291ACPZ-R7 belongs to Analog Devices' battery management IC product line, designed specifically for compact, safe, and flexible linear charging of single-cell Li+ batteries in portable consumer and industrial equipment.

FAQ

What is the maximum charge current supported by the ADP2291ACPZ-R7?

The ADP2291ACPZ-R7 supports up to 1.5 A charge current, achieved by setting the current sense resistor (RS) and ADJ pin voltage to yield a 150 mV sense voltage (V_RS). For example, with RS = 100 mΩ and ADJ open (3 V), ADP2291ACPZ-R7 delivers 1.5 A. Lower currents (e.g., 500 mA) are set by reducing V_RS to 50 mV using a 100 kΩ resistor from ADJ to GND.

Does the ADP2291ACPZ-R7 require an external blocking diode?

No, the ADP2291ACPZ-R7 features automatic reverse isolation: when VIN falls below BAT voltage, the DRV pin drives the external PNP base to BAT, turning off the pass transistor and preventing reverse current flow. This eliminates the need for an external blocking diode, reducing voltage drop, power loss, and component count.

How does the ADP2291ACPZ-R7 handle deeply discharged batteries?

The ADP2291ACPZ-R7 initiates precharge mode when BAT voltage is below 2.65–2.85 V, delivering reduced current (IMAX/10 at 3 V ADJ, IMAX/5 at 1.5 V ADJ). If voltage fails to rise above 2.85 V within the precharge timeout (typically 30 minutes), it enters battery fault shutdown. ADP2291ACPZ-R7 then requires VIN cycling to reset.

What package type is used for the ADP2291ACPZ-R7, and why does it matter?

The ADP2291ACPZ-R7 uses a 3 mm × 3 mm, 8-lead LFCSP package with exposed thermal pad. This package offers θ_JA = 48°C/W on a 4-layer PCB-significantly better than the MSOP-8 alternative (158°C/W)-enabling higher continuous power dissipation and improved reliability in thermally dense layouts typical of handheld devices.

Can the ADP2291ACPZ-R7 be used with input voltages below 4.5 V?

No-the ADP2291ACPZ-R7 has a minimum input voltage of 4.5 V per its Absolute Maximum Ratings and operating specifications. Below 3.8 V, the device enters power-down mode (drawing <1 µA from battery); between 3.8 V and 4.5 V, operation is undefined and not guaranteed. For sub-4.5 V inputs, a different charger IC such as the ADP2290 (3.6 V min) must be selected.