Texas Instruments

The bq24702/bq24703 is a highly integrated battery charge controller and selector tailored for notebook and sub-notebook PC applications. The bq24702/bq24703 uses dynamic power management (DPM) to minimize battery charge time by maximizing use of available wall-adapter power. This is achieved by dynamically adjusting the battery charge current based on the total system (adapter) current. The bq24702/bq24703 uses a fixed frequency, pulse width modulator (PWM) to accurately control battery charge current and voltage. Charge current limits can be programmed from a keyboard controller DAC or by external resistor dividers from the precision 5-V, ±0.6%, externally bypassed voltage reference (VREF), supplied by the bq24702/bq24703. The battery voltage limit can be programmed by using the internal 1.196-V, ±0.5% precision reference, making it suitable for the critical charging demands of lithium-ion cells. Also, the bq24702/bq24703 provides an option to override the precision reference and drive the error amplifier either directly from an external reference or from a resistor divider off the 5 V supplied by the integrated circuit. The selector function allows the manual selection of the system power source, battery or wall-adapter power. The bq24702/bq24703 supports battery-conditioning and battery-learn cycles through the ACSEL function. The ACSEL function allows manual selection of the battery or wall power as the main system power. It also provides autonomous switching to the remaining source (battery or ac power) should the selected system power source terminate (refer to Available Options table for the differences between the bq24702 and the bq24703). The bq24702/bq24703 also provides an alarm function to indicate a depleted battery condition. The bq24702/bq24703 PWM controller is ideally suited for operation in a buck converter for applications when the wall-adapter voltage is greater than the battery voltage. The bq24702/bq24703 is a highly integrated battery charge controller and selector tailored for notebook and sub-notebook PC applications. The bq24702/bq24703 uses dynamic power management (DPM) to minimize battery charge time by maximizing use of available wall-adapter power. This is achieved by dynamically adjusting the battery charge current based on the total system (adapter) current. The bq24702/bq24703 uses a fixed frequency, pulse width modulator (PWM) to accurately control battery charge current and voltage. Charge current limits can be programmed from a keyboard controller DAC or by external resistor dividers from the precision 5-V, ±0.6%, externally bypassed voltage reference (VREF), supplied by the bq24702/bq24703. The battery voltage limit can be programmed by using the internal 1.196-V, ±0.5% precision reference, making it suitable for the critical charging demands of lithium-ion cells. Also, the bq24702/bq24703 provides an option to override the precision reference and drive the error amplifier either directly from an external reference or from a resistor divider off the 5 V supplied by the integrated circuit. The selector function allows the manual selection of the system power source, battery or wall-adapter power. The bq24702/bq24703 supports battery-conditioning and battery-learn cycles through the ACSEL function. The ACSEL function allows manual selection of the battery or wall power as the main system power. It also provides autonomous switching to the remaining source (battery or ac power) should the selected system power source terminate (refer to Available Options table for the differences between the bq24702 and the bq24703). The bq24702/bq24703 also provides an alarm function to indicate a depleted battery condition. The bq24702/bq24703 PWM controller is ideally suited for operation in a buck converter for applications when the wall-adapter voltage is greater than the battery voltage.

The bq24707 and bq24707A devices are high-efficiency, synchronous battery chargers, offering low component count for space-constrained, multi-chemistry battery charging applications. SMBus controlled input current, charge current, and charge voltage DACs allow for very high regulation accuracies that can be easily programmed by the system power management micro-controller. The IC uses the internal input current register or external ILIM pin to throttle down PWM modulation to reduce the charge current. The IC provides anIFAULToutput to alarm if any MOSFET fault or input over current occurs. This alarm output allows users to turn off input power selectors when the fault occurs. Meanwhile, an independent comparator with internal reference is available to monitor input current, output current, or output voltage. The IC charges one-, two-, three-, or four-series Li+ cells, and is available in a 20-pin, 3.5 × 3.5 mmQFN package. The bq24707 and bq24707A devices are high-efficiency, synchronous battery chargers, offering low component count for space-constrained, multi-chemistry battery charging applications. SMBus controlled input current, charge current, and charge voltage DACs allow for very high regulation accuracies that can be easily programmed by the system power management micro-controller. The IC uses the internal input current register or external ILIM pin to throttle down PWM modulation to reduce the charge current. The IC provides anIFAULToutput to alarm if any MOSFET fault or input over current occurs. This alarm output allows users to turn off input power selectors when the fault occurs. Meanwhile, an independent comparator with internal reference is available to monitor input current, output current, or output voltage. The IC charges one-, two-, three-, or four-series Li+ cells, and is available in a 20-pin, 3.5 × 3.5 mmQFN package.

The bq24715 is a NVDC-1 synchronous battery charge controller with low quiescent current, high light load efficiency for 2S or 3S Li-ion battery charging applications, offering low component count. The power path management allows the system to be regulated at battery voltage but does not drop below the programmable system minimum voltage. The bq24715 provides N-channel ACFET and RBFET drivers for the power path management. It also provides driver of the external P-channel battery FET. The loop compensation is fully integrated. The bq24715 has programmable 11-bit charge voltage, 7-bit input/charge current and 6-bit minimal system voltage with very high regulation accuracies through the SMBus communication interface. The v monitors adapter current or battery discharge current through the IOUT pin allowing the host to throttle down CPU speed when needed. The bq24715 provides extensive safety features for over current, over voltage and MOSFET short circuit. The bq24715 is a NVDC-1 synchronous battery charge controller with low quiescent current, high light load efficiency for 2S or 3S Li-ion battery charging applications, offering low component count. The power path management allows the system to be regulated at battery voltage but does not drop below the programmable system minimum voltage. The bq24715 provides N-channel ACFET and RBFET drivers for the power path management. It also provides driver of the external P-channel battery FET. The loop compensation is fully integrated. The bq24715 has programmable 11-bit charge voltage, 7-bit input/charge current and 6-bit minimal system voltage with very high regulation accuracies through the SMBus communication interface. The v monitors adapter current or battery discharge current through the IOUT pin allowing the host to throttle down CPU speed when needed. The bq24715 provides extensive safety features for over current, over voltage and MOSFET short circuit.

The bq24721 is a high efficiency synchronous battery pack charger with high level of integration for portable applications. This device implements a high performance analog front-end that interfaces to the system power management micro-controller through a simplified SBS-like SMBus interface. The dynamic power management (DPM) function modifies the charge current depending on system load conditions, avoiding ac adapter overload. High accuracy current sense amplifiers enable accurate measurement of either the charge current or the ac adapter current, allowing termination of nonsmart packs and monitoring of overall system power. The adapter isolation diode can be bypassed or entirely replaced with an external MOSFET using a control signal provided by the bq24721, thus reducing overall power dissipation. Integrated features such as charger soft start, charge overcurrent protection, and IC temperature monitoring provide a second level of protection, in addition to pack and system protection functions. The bq24721 is a high efficiency synchronous battery pack charger with high level of integration for portable applications. This device implements a high performance analog front-end that interfaces to the system power management micro-controller through a simplified SBS-like SMBus interface. The dynamic power management (DPM) function modifies the charge current depending on system load conditions, avoiding ac adapter overload. High accuracy current sense amplifiers enable accurate measurement of either the charge current or the ac adapter current, allowing termination of nonsmart packs and monitoring of overall system power. The adapter isolation diode can be bypassed or entirely replaced with an external MOSFET using a control signal provided by the bq24721, thus reducing overall power dissipation. Integrated features such as charger soft start, charge overcurrent protection, and IC temperature monitoring provide a second level of protection, in addition to pack and system protection functions.

The bq24725 is a high-efficiency, synchronous battery charger, offering low component count for space-constraint, multi-chemistry battery charging applications. The bq24725 uses two charge pumps to separately drive n-channel MOSFETs (ACFET, RBFET and BATFET) for automatic system power source selection. SMBus controlled input current, charge current, and charge voltage DACs allow for high regulation accuracies that can be programmed by the system power management micro-controller. The bq24725 uses internal input current register or external ILIM pin to throttle down PWM modulation to reduce the charge current. The bq24725 charges two, three or four series Li+ cells, and is available in a 20-pin, 3.5 × 3.5 mm2QFN package. The bq24725 is a high-efficiency, synchronous battery charger, offering low component count for space-constraint, multi-chemistry battery charging applications. The bq24725 uses two charge pumps to separately drive n-channel MOSFETs (ACFET, RBFET and BATFET) for automatic system power source selection. SMBus controlled input current, charge current, and charge voltage DACs allow for high regulation accuracies that can be programmed by the system power management micro-controller. The bq24725 uses internal input current register or external ILIM pin to throttle down PWM modulation to reduce the charge current. The bq24725 charges two, three or four series Li+ cells, and is available in a 20-pin, 3.5 × 3.5 mm2QFN package.