ZHCSOK3 august 2023 BQ25756
PRODUCTION DATA
- 1
- 1 特性
- 2 应用
- 3 说明
- 4 Revision History
- 5 说明（续）
- 6 Pin Configuration and Functions
- 7 Specifications
-
8 Detailed Description
- 8.1 Overview
- 8.2 Functional Block Diagram
- 8.3
Feature Description
- 8.3.1 Device Power-On-Reset
- 8.3.2 Device Power-Up From Battery Without Input Source
- 8.3.3 Device Power Up from Input Source
- 8.3.4 Battery Charging Management
- 8.3.5 Power Management
- 8.3.6 Reverse Mode Power Direction
- 8.3.7 Integrated 16-Bit ADC for Monitoring
- 8.3.8 Status Outputs (PG, STAT1, STAT2, and INT)
- 8.3.9
Protections
- 8.3.9.1
Voltage and Current Monitoring
- 8.3.9.1.1 VAC Over-voltage Protection (VAC_OVP)
- 8.3.9.1.2 VAC Under-voltage Protection (VAC_UVP)
- 8.3.9.1.3 Battery Over-voltage Protection (BAT_OVP)
- 8.3.9.1.4 Battery Over-current Protection (BAT_OCP)
- 8.3.9.1.5 Reverse Mode Over-voltage Protection (REV_OVP)
- 8.3.9.1.6 Reverse Mode Under-voltage Protection (REV_UVP)
- 8.3.9.1.7 DRV_SUP Under-voltage and Over-voltage Protection (DRV_OKZ)
- 8.3.9.1.8 REGN Under-voltage Protection (REGN_OKZ)
- 8.3.9.2 Thermal Shutdown (TSHUT)
- 8.3.9.1
Voltage and Current Monitoring
- 8.3.10 Serial Interface
- 8.4 Device Functional Modes
- 8.5 BQ25756 Registers
-
9 Application and Implementation
- 9.1 Application Information
- 9.2
Typical Applications
- 9.2.1
Typical Application
- 9.2.1.1 Design Requirements
- 9.2.1.2
Detailed Design Procedure
- 9.2.1.2.1 ACUV / ACOV Input Voltage Operating Window Programming
- 9.2.1.2.2 Charge Voltage Selection
- 9.2.1.2.3 Switching Frequency Selection
- 9.2.1.2.4 Inductor Selection
- 9.2.1.2.5 Input (VAC) Capacitor
- 9.2.1.2.6 Output (VBAT) Capacitor
- 9.2.1.2.7 Sense Resistor (RAC_SNS and RBAT_SNS) and Current Programming
- 9.2.1.2.8 Power MOSFETs Selection
- 9.2.1.2.9 Converter Fast Transient Response
- 9.2.1.3 Application Curves
- 9.2.2 Typical Application (USB-PD EPR Configuration)
- 9.2.1
Typical Application
- 10Power Supply Recommendations
- 11Layout
- 12Device and Documentation Support
- 13Mechanical, Packaging, and Orderable Information
8.3.3.1 VAC Operating Window Programming (ACUV and ACOV)
The VAC operating window can be programmed via the ACUV and ACOV pins using a three-resistor divider from VAC to PGND as shown in Figure 8-1.
Figure 8-1 ACUV and ACOV ProgrammingWhen VACUV falls and reaches VACUV_DPM, the device enters input voltage regulation, thereby reducing the charge current. VACUV continues falling below VREF_ACUV, the device automatically stops the converter and the PG pin pulls high.
System Note: if VAC_DPM register is programmed to a value higher than POR, the device regulates the VAC voltage to the higher of VAC_DPM register or VACUV_DPM pin voltage. Refer to Section 8.3.5.1.2 for more information.
When VACOV rises above VREF_ACOV, the device automatically stops the converter and the PG pin pulls high.
The following equations govern the relationship between the resistor divider and the target operating voltage window programmed by ACOV and ACUV pins:
If unused, tie ACUV to VAC and ACOV to PGND in order to apply the internal VAC operating window (VVAC_OP).