Overview
The ADP2291ARMZ-R7, produced by Analog Devices Inc., is a compact, constant-current/constant-voltage linear charger designed for single-cell lithium-ion batteries. This charger operates from a wide input voltage range of 4.5 V to 12 V and is known for its simplicity and safety features. It requires only a few external components to provide a complete charging system, making it ideal for various portable electronic devices. The ADP2291 features an internally controlled, multistep charging cycle that includes precharge, fast charge, and end-of-charge modes to optimize battery life and safety.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Input Voltage | 4.5 | - | 12 | V |
| Maximum Charge Current | - | - | 1.5 | A |
| Battery Voltage Accuracy (End-of-Charge) | 4.158 | 4.2 | 4.242 | V |
| Load Regulation (No Battery) | -80 | - | - | mV |
| Current Draw (Fast Charge/Precharge/End-of-Charge) | 6 | 1.4 | 9 | mA |
| Shutdown Supply Current | - | - | 1 | µA |
| Charge Timer Current | 21.0 | 24.0 | 27.0 | µA |
| Overshoot Protection Threshold | 4.7 | - | 5.3 | V |
Key Features
- Adjustable charging current up to 1.5 A using an external resistor.
- Internally controlled, multistep charging cycle including precharge, fast charge, and end-of-charge modes.
- Automatic reverse isolation with no external blocking diode required.
- Output overshoot protection to safeguard against voltage spikes during battery disconnect.
- Thermal shutdown and charging stop mode for battery faults.
- Programmable termination timer and LED charging status indicator.
- Low cost PNP external pass element and small package options (8-lead MSOP and 3 × 3 mm LFCSP).
Applications
- Wireless handsets
- Smart handhelds and PDAs
- Digital cameras
- Single-cell, lithium-ion-powered systems
- Cradle chargers
Q & A
- What is the input voltage range of the ADP2291? The input voltage range is from 4.5 V to 12 V.
- What is the maximum charge current of the ADP2291? The maximum charge current is up to 1.5 A.
- Does the ADP2291 require an external blocking diode? No, it features automatic reverse isolation without the need for an external blocking diode.
- What safety features does the ADP2291 include? It includes output overshoot protection, thermal shutdown, and charging stop mode for battery faults.
- How is the charging status indicated? The ADP2291 includes an LED driver to indicate the battery charging status.
- What are the package options for the ADP2291? It is available in 8-lead MSOP and 3 × 3 mm LFCSP packages.
- What is the accuracy of the battery voltage at the end of charge? The battery voltage accuracy at the end of charge is ±1% over line and temperature, with a voltage of 4.2 V.
- Does the ADP2291 support trickle charge mode? Yes, it includes a trickle charge mode for deeply discharged cells.
- What is the shutdown supply current of the ADP2291? The shutdown supply current is less than 1 µA.
- Can the charge timer be programmed? Yes, the charge timer can be programmed using an external capacitor).
