Texas Instruments BQ25853-Q1 Bidirectional Charge Controller
Texas Instruments BQ25853-Q1 Bidirectional Charge Controller is a wide-input-voltage, switched-mode buck-boost controller that supports bidirectional power flow. The device provides precise supercapacitor charge-current and charge-voltage regulation, integrated loop compensation, soft start, and autonomous backup operation. Designers can use I²C host control or configure standalone charging limits through external resistors.
The Texas Instruments BQ25853-Q1 integrates a 16-bit ADC for voltage, current, and temperature monitoring. Adjustable input protection, overvoltage and overcurrent protection, thermistor monitoring, charge timers, and thermal shutdown support reliable operation. The controller is ideal for automotive backup power designs, including low-voltage battery systems, battery management units, domain gateways, ADAS domain controllers, and front door modules.
Features
- BQ25853-Q1 AEC-Q100 qualified for automotive applications
- Temperature grade 1
- Human body model electrostatic discharge classification of ±2000V
- Charged device model electrostatic discharge classification of ±750V for corner pins and ±500V for all pins
- Functional Safety-Capable
- Documentation available to aid functional safety system design
- Synchronous buck-boost controller with NFET drivers
- Buck-only mode configurable with MODE pin
- Switching-frequency dithering for EMI noise reduction
- Optional synchronization to external clock
- Integrated loop compensation with soft start
- Optional gate-driver supply input for optimized efficiency
- Bidirectional converter operation with autonomous backup mode
- Reverse-mode system-voltage programming with a resistor divider
- Programmable reverse-mode automatic entry and exit thresholds
- I²C-controlled operation with resistor-programmable option
- Hardware-adjustable input and output current limits
- Integrated 16-bit ADC for voltage, current, and temperature monitoring
- High safety integration
- Adjustable input overvoltage and undervoltage protection
- Overvoltage and overcurrent protection
- Thermal shutdown
Applications
- Low-voltage battery system
- Battery management unit
- Domain gateway
- ADAS domain controller
- Front door module
Specifications
- Input voltage operating range of 4.4V to 70V
- Supercapacitor charging output voltage of up to 70V
- Adjustable switching-frequency range of 200kHz to 600kHz
- Adjustable output current regulation of up to 35A using a 2.5mΩ resistor
- Charge-voltage regulation accuracy of ±0.5%
- Charge- and input-current regulation accuracy of ±3%
- Reverse-mode voltage-regulation accuracy of ±0.5%
- Input-voltage regulation accuracy of ±2%
- Ambient operating temperature range of -40°C to +150°C
- 36-pin QFN package with wettable flanks
- Package dimensions of 5mm x 6mm
- Pin pitch of 0.5mm
Simplified Schematic
Block Diagram
