ZHCSKL0D December 2009 – December 2019 BQ24610 , BQ24617
PRODUCTION DATA.
- 1 特性
- 2 應用
- 3 說明
- 4 修訂歷史記錄
- 5 說明 （續）
- 6 Device Comparison Table
- 7 Pin Configuration and Functions
- 8 Specifications
-
9 Detailed Description
- 9.1 Overview
- 9.2 Functional Block Diagram
- 9.3
Feature Description
- 9.3.1 Battery Voltage Regulation
- 9.3.2 Battery Current Regulation
- 9.3.3 Input Adapter Current Regulation
- 9.3.4 Precharge
- 9.3.5 Charge Termination, Recharge, and Safety Timer
- 9.3.6 Power Up
- 9.3.7 Enable and Disable Charging
- 9.3.8 System Power Selector
- 9.3.9 Automatic Internal Soft-Start Charger Current
- 9.3.10 Converter Operation
- 9.3.11 Synchronous and Nonsynchronous Operation
- 9.3.12 Cycle-by-Cycle Charge Undercurrent Protection
- 9.3.13 Input Overvoltage Protection (ACOV)
- 9.3.14 Input Undervoltage Lockout (UVLO)
- 9.3.15 Battery Overvoltage Protection
- 9.3.16 Cycle-by-Cycle Charge Overcurrent Protection
- 9.3.17 Thermal Shutdown Protection
- 9.3.18 Temperature Qualification
- 9.3.19 Timer Fault Recovery
- 9.3.20 PG Output
- 9.3.21 CE (Charge Enable)
- 9.3.22 Charge Status Outputs
- 9.3.23 Battery Detection
- 9.4 Device Functional Modes
- 10Application and Implementation
- 11Power Supply Recommendations
- 12Layout
- 13器件和文檔支持
- 14機械、封裝和可訂購信息
封裝選項
機械數據 (封裝 | 引腳)
- RGE|24
散熱焊盤機械數據 (封裝 | 引腳)
- RGE|24
訂購信息
9.3.5 Charge Termination, Recharge, and Safety Timer
The BQ2461x monitors the charging current during the voltage regulation phase. When VTTC is valid, termination is detected while the voltage on the VFB pin is higher than the VRECH threshold AND the charge current is less than the ITERM threshold, as calculated in Equation 5:
The input voltage of ISET2 is from 0 V to 2 V. The minimum precharge/termination current is clamped to be around 125 mA with default 10-mΩ sensing resistor. As a safety backup, the BQ2461x also provides a programmable charge timer. The charge time is programmed by the capacitor connected between the TTC pin and GND, and is given by Equation 6
where
- CTTC (range from 0.01 µF to 0.11 µF to give 1- to 10-h safety time) is the capacitor connected from TTC pin to GND.
- KTTC is the constant multiplier (5.6 min/nF).
A new charge cycle is initiated and safety timer is reset when one of the following conditions occurs:
- The battery voltage falls below the recharge threshold.
- A power-on-reset (POR) event occurs.
- CE is toggled.
The TTC pin may be taken LOW to disable termination and to disable the safety timer. If TTC is pulled to VREF, the BQ2461x continues to allow termination, but disables the safety timer. TTC taken low resets the safety timer. When ACOV, VCCLOWV, and SLEEP mode resume normal, the safety timer is reset.