DESCRIPTION The BENCHMARQ bq2057 series advanced Lithium-Ion (Li-Ion) and Lithium-Polymer (Li-Pol) linear charge-management ICs are designed for cost sensitive and compact portable electronics. They combine high-accuracy current and voltage regulation, battery conditioning, temperature monitoring, charge termination, charge-status indication, and AutoComp charge-rate compensation in a single 8-pin IC. MSOP, TSSOP, and SOIC package options are offered to fit a wide range of end applications. FEATURES Ideal for Single (4.1 V or 4.2 V) and Dual-Cell (8.2 V or 8.4 V) Li-Ion or Li-Pol Packs Requires Small Number of External Components 0.3 V Dropout Voltage for Minimizing Heat Dissipation Better Than ±1% Voltage Regulation Accuracy With Preset Voltages AutoCompDynamic Compensation of Battery Pack’s Internal Impedance to Reduce Charge Time Optional Cell-Temperature Monitoring Before and During Charge Integrated Voltage and Current Regulation With Programmable Charge-Current and High or Low-Side Current Sensing Integrated Cell Conditioning for Reviving Deeply Discharged Cells and Minimizing Heat Dissipation During Initial Stage Of Charge Charge Status Output for Single or Dual Led or Host Processor Interface Automatic Battery-Recharge Feature Charge Termination by Minimum Current Automatic Low-Power Sleep Mode When VCC Is Removed EVMs Available for Quick Evaluation Packaging: 8-Pin SOIC, 8-Pin TSSOP, 8-Pin MSOP
The BQ2057TTS is a low dropout linear 2-cell Li-ion Charge Controller with 8.2V AutoComp. It is designed for cost-sensitive and compact portable electronics. They combine high-accuracy current and voltage regulation, battery conditioning, temperature monitoring, charge termination, charge-status indication and AutoComp charge-rate compensation in a single 8-pin IC. The BQ2057 continuously measures battery temperature using an external thermistor. For safety, it inhibits charge until the battery temperature is within user-defined thresholds. It charges the battery in three phases: conditioning, constant current and constant voltage. If the battery voltage is below the low-voltage threshold, V(min), It pre-charges using a low current to condition the battery. The conditioning charge rate is approximately 10% of the regulation current. The conditioning current also minimizes heat dissipation in the external pass-element during the initial stage of the charge.