BQ2004E Overview
The bq2004E and bq2004H Fast Charge ICs provide prehensive fast charge control functions together with high-speed switching power control circuitry on a monolithic CMOS device. Integration of closed-loop current control circuitry allows the bq2004 to be the basis of a cost-effective solution for stand-alone and systemintegrated chargers for batteries of one or more cells. Switch-activated discharge-beforecharge allows bq2004E/H-based chargers to support battery conditioning and capacity determination. High-efficiency power conversion is acplished using the bq2004E/H as a hysteretic PWM controller for switch-mode regulation of the charging current. The bq2004E/H may alternatively be used to gate an externally regulated charging current. Fast charge may begin on application of the charging supply, replacement of the battery, or switch depression. For safety, fast charge is inhibited...
BQ2004E Key Features
- Fast charge and conditioning of nickel cadmium or nickel-metal hydride batteries
- Hysteretic PWM switch-mode current regulation or gated control of an external regulator
- Easily integrated into systems or used as a stand-alone charger
- Pre-charge qualification of temperature and voltage
- Configurable, direct LED outputs display battery and charge status
- Fast-charge termination by ∆ temperature/∆ time, peak volume detection, -∆V, maximum voltage, maximum temperature, and m
- Optional top-off charge and pulsed current maintenance charging
- Logic-level controlled low-power mode (< 5µA standby current)
- APRIL 2005