TI 公司的bq27741-G1是用于單個電池組的鋰電池電量檢測集成電路,提供計于硬件的過壓和欠壓保護,充電時的過流保護以及短路保護.采用專利的Impedance Track™算法,提供剩余容量(mAh),充電狀態(tài)(%),剩余工作時間,電池電壓(mV)和溫度(℃),主要用在智能手機,PDA,數(shù)碼相機和攝像機,手持終端,MP3或多媒體播放器.本文介紹了bq27741-G1主要特性,兩種參考應用電路以及bq27741-G1評估模塊(EVM)特性, 和電池與系統(tǒng)負載/充電器連接圖,電路圖,材料清單和PCB元件布局圖.
The Texas Instruments bq27741-G1 Li-Ion battery fuel gauge is a microcontroller peripheral that provides fuel gauging for single-cell Li-Ion battery packs. The device requires little system microcontroller firmware development for accurate battery fuel gauging. The fuel gauge resides within the battery pack or on the system’s main board with an embedded battery (non-removable). The fuel gauge provides hardware-based over- and undervoltage, overcurrent in charge or discharge, and short-circuit protections.
The fuel gauge uses the patented Impedance Track™ algorithm for fuel gauging, and provides information such as remaining battery capacity (mAh), state-of-charge (%), run-time to empty (minimum), battery voltage (mV), and temperature (°C), as well as recording vital parameters throughout the lifetime of the battery.
The CSP is a 15-ball package (2.776 mm × 1.96 mm) that is ideal for space-constrained applications.
bq27741-G1主要特性:
Battery Fuel Gauge and Protector for 1-Series Li-Ion Applications
Microcontroller Peripheral Provides:
Accurate Battery Fuel Gauging Supports up to 32 Ahr
External and Internal Temperature Sensors for Battery
Temperature Reporting
Precision 16-bit High-Side Coulomb Counter with
High-Side Low-Value Sense Resistor (5 mΩ to 20 mΩ)
Lifetime and Current Data Logging
64 Bytes of Non-Volatile Scratch Pad Flash
SHA-1/HMAC Authentication
Battery Fuel Gauging Based on Patented Impedance Track Technology
Models Battery Discharge Curve for Accurate Time-To-Empty Predictions
Automatically Adjusts for Aging, Self-Discharge, and Temperature- and Rate-Induced Effects on Battery
Advanced Fuel Gauging Features
Internal Short Detection
Tab Disconnection Detection
Safety and Protection:
Over- and Undervoltage Protection with Brown-out Low-Power Mode
Overcharging and Discharging Current Protection
Overtemperature Protection
Short-Circuit Protection
Low-Voltage Notification
Voltage Doubler to Support High-side NFET Protection
HDQ and I2C Interface Formats for Communication With Host System
Small 15-ball NanoFree (CSP) Packaging
bq27741-G1應用:
Smartphones
PDAs
Digital Still and Video Cameras
Handheld Terminals
MP3 or Multimedia Players
圖1. bq27741-G1參考電路:I2C模式
圖2. bq27741-G1參考電路:HDQ模式
bq27741-G1評估模塊(EVM)
This evaluation module (EVM) is a complete evaluation system for the bq27741-G1. The EVM includes one bq27741 circuit module, a current sense resistor, two thermistors, and two protection N-FETs. An EV2400 PC interface board and a PC USB cable are required for gas gauge interface, but must be ordered separately. The circuit module includes one bq27741 integrated circuit and all other onboard components necessary to monitor and predict capacity for a pack-side fuel gauge solution and to perform the protection. The circuit module connects directly across the battery cell. With the EV2400 interface
board and software, the user can read the bq27741 data registers, program the chipset for different pack configurations, log cycling data for further evaluation, and evaluate the overall functionality of the bq27741 solution under different charge and discharge conditions. The latest Windows™-based PC software can be downloaded from the product folder on the Texas Instruments Web site.
bq27741-G1評估模塊(EVM)特性:
• Complete evaluation system for the bq27741 gas gauge with Impedance Track™ Technology
• Populated circuit module for quick setup
• Personal computer (PC) software and interface board for easy evaluation
• Software that allows data logging for system analysis
• Ability to upgrade to the latest firmware version by flash reprogramming
圖3.bq27741-G1評估模塊(EVM)外形圖
圖4.bq27741-G1評估模塊(EVM)和電池與系統(tǒng)負載/充電器連接圖
圖5.bq27741-G1評估模塊(EVM)電路圖
bq27741-G1評估模塊(EVM)材料清單(BOM):
圖6.bq27741-G1評估模塊(EVM)元件布局圖 |
