BQ29311PWR

Product Overview

Category

BQ29311PWR belongs to the category of integrated circuits (ICs) used in battery protection systems.

Use

This IC is primarily used for protecting lithium-ion and lithium-polymer batteries from overcharging, over-discharging, and short-circuiting.

Characteristics

• Voltage range: 2.5V to 4.8V
• Low quiescent current: 10µA (typical)
• Overvoltage protection threshold: adjustable from 3.9V to 4.6V
• Undervoltage protection threshold: adjustable from 2.1V to 3.0V
• Short-circuit detection delay: adjustable from 40µs to 640µs
• Package type: TSSOP-20
• Essence: Battery protection and monitoring

Packaging/Quantity

The BQ29311PWR IC is available in a TSSOP-20 package. It is typically sold in reels containing 2500 units per reel.

Specifications

• Operating voltage range: 2.5V to 4.8V
• Operating temperature range: -40°C to +85°C
• Overvoltage protection threshold range: 3.9V to 4.6V
• Undervoltage protection threshold range: 2.1V to 3.0V
• Short-circuit detection delay range: 40µs to 640µs
• Quiescent current: 10µA (typical)
• Maximum continuous discharge current: 10A
• Maximum continuous charge current: 5A

Detailed Pin Configuration

The BQ29311PWR IC has a total of 20 pins. The pin configuration is as follows:

1. VDD: Power supply input
2. VSS: Ground
3. SDA: I2C data input/output
4. SCL: I2C clock input
5. ALERT: Open-drain output for fault indication
6. TS1: Thermistor input 1
7. TS2: Thermistor input 2
8. BAT: Battery voltage sense input
9. VC1: Cell 1 voltage sense input
10. VC2: Cell 2 voltage sense input
11. VC3: Cell 3 voltage sense input
12. VC4: Cell 4 voltage sense input
13. VC5: Cell 5 voltage sense input
14. VC6: Cell 6 voltage sense input
15. VC7: Cell 7 voltage sense input
16. VC8: Cell 8 voltage sense input
17. VC9: Cell 9 voltage sense input
18. VC10: Cell 10 voltage sense input
19. VC11: Cell 11 voltage sense input
20. VC12: Cell 12 voltage sense input

Functional Features

The BQ29311PWR offers the following functional features:

• Overvoltage protection: Monitors battery voltage and disconnects the load when it exceeds the set threshold.
• Undervoltage protection: Cuts off the load when the battery voltage drops below the set threshold.
• Short-circuit detection: Detects short circuits and disables the load to prevent damage.
• Temperature monitoring: Allows connection of thermistors to monitor battery temperature.
• I2C communication: Supports communication with a microcontroller through the I2C interface.
• Fault indication: Provides an open-drain output to indicate any detected faults.

Advantages and Disadvantages

Advantages

• Comprehensive battery protection against overcharging, over-discharging, and short-circuits.
• Adjustable thresholds for voltage protection.
• Low quiescent current, minimizing power consumption.
• Supports temperature monitoring for enhanced safety.

Disadvantages

• Limited to 12-cell battery systems.
• Requires external thermistors for temperature monitoring.
• Relatively high short-circuit detection delay compared to some alternatives.

Working Principles

The BQ29311PWR operates by continuously monitoring the battery voltage and comparing it with the set thresholds. When the voltage exceeds the overvoltage threshold, the IC disconnects the load to prevent overcharging. Similarly, when the voltage drops below the undervoltage threshold, the load is disconnected to avoid over-discharging. The short-circuit detection feature quickly detects any short circuits and disables the load to protect the battery and system.

Detailed Application Field Plans

The BQ29311PWR is commonly used in various applications requiring battery protection, such as:

1. Electric vehicles (EVs) and hybrid electric vehicles (HEVs)
2. Portable electronic devices (e.g., smartphones, tablets, laptops)
3. Power tools
4. Uninterruptible power supplies (UPS)
5. Energy storage systems

Detailed and Complete Alternative Models

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