Overview
The Texas Instruments BQ27Z746 is a highly integrated battery gas gauge and protection solution designed for 1-series cell Li-ion and Li-polymer battery packs. This device combines an ultra-low power TI BQBMP processor, high accuracy analog measurement capabilities, and integrated flash memory to provide a comprehensive battery management solution. The BQ27Z746 features Impedance Track™ technology, which models the battery discharge curve to predict time-to-empty accurately, adjusting for aging, temperature, and rate-induced effects on the battery.
The device communicates through an I2C compatible interface and includes a flash-programmable custom RISC CPU with SHA-256 authentication. It also offers programmable hardware-based protection, including overvoltage, undervoltage, overcurrent, and short circuit protections. The BQ27Z746 operates in various low-power modes, such as SLEEP, SHIP, SHELF, and SHUTDOWN, making it suitable for a wide range of battery-powered applications.
Key Specifications
| Parameter | Minimum | Typical | Maximum | Unit |
|---|---|---|---|---|
| Supply Voltage Range (VDD) | 2.0 | 5.5 | 6 | V |
| Operating Temperature (TA) | -40 | 85 | °C | |
| Current Sense Resistor Range (RSNS) | 1 | 20 | mΩ | |
| Standard Operating Current (INORMAL) | 57 | µA | ||
| SLEEP Mode Current (ISLEEP) | 20 | µA | ||
| SHIP Mode Current (ISHIP) | 10 | µA | ||
| SHELF Mode Current (ISHELF) | 5 | µA | ||
| SHUTDOWN Mode Current (ISHUT) | 0.2 | µA | ||
| I2C Bus Frequency | 400 kHz |
Key Features
- Integrated battery gas gauge and protector using Impedance Track™ technology for accurate battery state of charge and time-to-empty predictions.
- Flash-programmable custom RISC CPU with SHA-256 authentication.
- Ultra-low power operation with multiple power modes: SLEEP, SHIP, SHELF, and SHUTDOWN.
- High accuracy analog measurement capabilities, including two independent precision 16-bit ADCs for current and voltage sensing.
- Programmable hardware-based protection: overvoltage, undervoltage, overcurrent in discharge and charge, and short circuit protections.
- I2C compatible interface for communication.
- Differential battery sensing analog output pins with built-in protection.
- High-side or low-side current sensing options.
- Firmware-based overtemperature protection.
Applications
- Smartphones and tablets.
- Cameras and other portable consumer electronics.
- Portable wearables and medical devices.
- Industrial handheld devices.
Q & A
- What is the primary function of the BQ27Z746?
The BQ27Z746 is a highly integrated battery gas gauge and protection solution for 1-series cell Li-ion and Li-polymer battery packs.
- What communication interface does the BQ27Z746 use?
The BQ27Z746 communicates through an I2C compatible interface.
- What is Impedance Track™ technology?
Impedance Track™ technology models the battery discharge curve to predict time-to-empty accurately, adjusting for aging, temperature, and rate-induced effects on the battery.
- What are the different power modes of the BQ27Z746?
The device operates in SLEEP, SHIP, SHELF, and SHUTDOWN modes to minimize power consumption.
- What types of protection does the BQ27Z746 offer?
The device offers programmable hardware-based protection including overvoltage, undervoltage, overcurrent in discharge and charge, and short circuit protections, as well as firmware-based overtemperature protection.
- How does the BQ27Z746 sense battery current?
The BQ27Z746 can sense battery current using either high-side or low-side current sensing configurations.
- What is the typical operating current of the BQ27Z746 in standard mode?
The typical operating current in standard mode is 57 µA.
- What is the purpose of the SHA-256 authentication in the BQ27Z746?
The SHA-256 authentication is used for secure firmware updates and device verification.
- What are some common applications of the BQ27Z746?
Common applications include smartphones, tablets, cameras, portable wearables, medical devices, and industrial handheld devices.
- How does the BQ27Z746 handle temperature sensing?
The device can use either an external temperature sensor or an onboard temperature sensor for temperature sensing.
