AIC1761

Features:

Reliable Fast Charge Control of NiMH/NiCd Batteries.
Quick and Easy Testing for Production.
Fast Charge Termination by:
1. Accurate -∆V Detection Level with Respect to Peak Battery Voltage Value.
AIC1761 ........................ -1%
AIC1766 ........................-0.25%
2. Peak Voltage Timer (0∆V).
Adjustable Fast Charge Safety Timer.
Protection against Temperature Fault.
Protection against Short-Circuited and Open Batteries.
Wide Operation Voltage Range: 9V to 18V, no Extra Regulator Needed.
Large Battery Voltage Detection Range: 0.65V to 3.7V.
LED Drivers to Indicate Charge Status or Fault Conditions.
Voltage Reference Output.
Space-Saving Packages:
8-PIN DIP, SO
14-PIN DIP, SO

Application

Battery Chargers for :
Mobile Phones
Notebook and Laptop Personal Computers
Portable Power Tools and Toys
Portable Communication Equipments
Portable Video and Stereo Equipments


Specifications

Supply Voltage ......................................................................................................... 18V
DC Voltage Applied on any Pin ................................................................................... 18V
Sink Current of VOUT Pin, LED Pin, and FLASH Pin ....................................................20mA
Operating Temperature Range ................................................................... 0°C to 70°C
Storage Temperature Range ................................................................. -65°C to 150°C


Description

The AIC1761/1766 fast charge controller IC is designed for intelligent charging of NiMH or NiCd batteries without overcharging. It detects a voltage drop (-∆V) occurring in the final stage of a fast charging cycle and correspondingly controls the charging current. Fast charge can also be cut off by a peak voltage timer (0∆V).
The detection of -∆V is a very reliable method to terminate fast charging for NiMH and NiCd batteries. The AIC1761/1766 uses -∆V detection as one of primary decisions for fast charge cut-off. The - ∆V value for the AIC1761 is as small as 16mV per cell, suitable for NiCd batteries. The -∆V value for the AIC1766 is as small as 4mV per cell, particularly suitable for NiMH as well as the NiCd batteries. The peak voltage timer is particularly useful when the voltage drop at the end of charge for some batteries, e.g. NiMH cells, is not pronounced enough for reliable detection. An adjustable safety timer (3 settings) is used as a backup termination method. Provisions are made with the AIC1761/1766 to prevent fast charge under temperature fault conditions. Two LED outputs are used to indicate the charging status. Another flash LED output can be used alone to indicate charge status.
AC mode allows the battery to drive its loads while being charged. Test mode is provided to dramatically reduce production test time.