BQ76925
- Analog interface for host cell measurement
- Cell input MUX, level shifter, and scaler
- 1.5-/ 3.0-V low-drift, calibrated reference allows accurate analog-to-digital conversions
- Analog interface for host current measurement
- Variable gain current sense amplifier capable of operation with 1-mΩ sense resistor
- Switchable thermistor bias output for host temperature measurements
- Overcurrent comparator with dynamically adjustable
threshold
- Alerts host to potential overcurrent faults
- Wakes up host on load connect
- Integrated cell balancing FETs
- Individual host control
- 50 mA per cell balancing current
- Supports cell sense-line open wire detection
- Integrated 3.3-V regulator for powering micro-controller or LEDs
- I2C interface for host
communications
- Optional packet CRC for robust operation
- Supply voltage range from 4.2 V to 26.4 V
- Low power consumption
- 40 µA typical in NORMAL mode
- 1.5 µA maximum in SLEEP mode
- 20-pin TSSOP or 24-pin VQFN package
The BQ76925 host-controlled analog front end (AFE) is part of a complete pack monitoring, balancing, and protection system for 3-, 4-, 5-, or 6-series cell li-ion and li-polymer batteries. The BQ76925 device allows a host controller to monitor individual cell voltages, pack current and temperature easily. The Host may use this information to determine unsafe or faulty operating conditions such as overvoltage, undervoltage, overtemperature, overcurrent, cell imbalance, state of charge, and state of health conditions.
Cell input voltages are level-shifted, multiplexed, scaled, and output for measurement by a host ADC. A dedicated pin provides a low-drift calibrated reference voltage to enable accurate measurements.
The voltage across an external-sense resistor is amplified and output to a host ADC for both charge and discharge current measurements. Two gain settings enable operation with a variety of sense resistor values over a wide range of pack currents.
To enable temperature measurements by the host, the AFE provides a separate output pin for biasing an external thermistor network. This output can be switched on and off under host control to minimize power consumption.
The BQ76925 device includes a comparator with a dynamically selectable threshold for monitoring current. The comparator result is driven through an open-drain output to alert the host when the threshold is exceeded. This feature can be used to wake up the host on connection of the load, or to alert the host to a potential fault condition.
The BQ76925 device integrates cell balancing FETs that are fully controlled by the host. The balancing current is set by external resistors up to a maximum value of 50 mA. These same FETs may be utilized in conjunction with cell voltage measurements to detect an open wire on a cell sense-line.
The host communicates with the AFE through an I2C interface. A packet CRC may optionally be used to ensure robust operation. The device may be put into a low-current sleep mode through the I2C interface and awakened by pulling up the ALERT pin.
技術資料
| 上位の文書 | タイプ | タイトル | フォーマットオプション | 最新の英語版をダウンロード | 日付 | |
|---|---|---|---|---|---|---|
| * | データシート | BQ76925 3-Series to 6-Series Cell Li-Ion and Li-Phosphate Battery Monitor (Analog Front End) データシート (Rev. E) | PDF | HTML | 2020/04/21 | ||
| アプリケーション・ノート | Getting Started With the bq76925 (Rev. B) | 2019/12/09 | ||||
| アプリケーション・ノート | 3~6 Cells Battery Management System Based On BQ76925+MSP430G2xx2 | 2014/03/20 |
設計と開発
その他のアイテムや必要なリソースを参照するには、以下のタイトルをクリックして詳細ページをご覧ください。
BQ76925EVM — 評価基板、BQ76925 用、アナログ・フロント・エンド、3 ～ 6 直列リチウムイオン・セル用
BQ76925EVM は、BQ76925 アナログ・フロント・エンド向けの評価基板であり、3 ～ 6 個の直列接続リチウムイオン・セルに対応しています。BQ76925EVM 評価基板のユーザー・ガイドを活用すると、BQ76925 の評価が容易になります。このガイドは、基板のセットアップと動作を説明し、回路図、部品表 (BOM)、プリント基板レイアウトも掲載しています。BQ76925を使用してバッテリ管理システムを設計する前に、BQ76925 データシートを読むことをお勧めします。設計者が Windows ベースの PC からこの評価基板と通信しようとする場合、個別の USB (...)
SLUC581 — bq76925 Example Code
SLUC268 — bq76925 Evaluation Software
| パッケージ | ピン数 | CAD シンボル、フットプリント、および 3D モデル |
|---|---|---|
| TSSOP (PW) | 20 | Ultra Librarian |
| VQFN (RGE) | 24 | Ultra Librarian |
購入と品質
推奨製品には、この TI 製品に関連するパラメータ、評価基板、またはリファレンス デザインが存在する可能性があります。