SLUSF18B
October 2023 – May 2026
BQ25638
PRODUCTION DATA
1
1
Features
2
Applications
3
Description
4
Description (continued)
5
Pin Configuration and Functions
6
Specifications
6.1
Absolute Maximum Ratings
6.2
ESD Ratings
6.3
Recommended Operating Conditions
6.4
Thermal Information
6.5
Electrical Characteristics
6.6
Timing Requirements
6.7
Typical Characteristics
7
Detailed Description
7.1
Overview
7.2
Functional Block Diagram
7.3
Feature Description
7.3.1
Power-On-Reset (POR)
7.3.2
Device Power Up from Battery
7.3.3
Device Power Up from Input Source
7.3.3.1
REGN LDO Power Up
7.3.3.2
Poor Source Qualification
7.3.3.3
Input Voltage Limit Threshold Setting (VINDPM Threshold)
7.3.3.4
Converter Power-Up
7.3.3.5
Input Current Optimizer (ICO)
7.3.3.6
Switching Frequency and Dithering Feature
7.3.4
Power Path Management
7.3.4.1
Narrow VDC Architecture
7.3.4.2
Dynamic Power Management
7.3.4.2.1
Input Current Limit on ILIM Pin
7.3.4.3
High Impedance (HIZ) Mode
7.3.5
Battery Charging Management
7.3.5.1
Autonomous Charging Cycle
7.3.5.2
Battery Charging Profile
7.3.5.3
Charging Termination
7.3.5.4
Thermistor Qualification
7.3.5.4.1
Advanced Temperature Profile in Charge Mode
7.3.5.4.2
TS Pin Thermistor Configuration
7.3.5.4.3
Cold/Hot Temperature Window in OTG Mode
7.3.5.4.4
JEITA Charge Rate Scaling
7.3.5.4.5
TS_BIAS Pin
7.3.5.5
Charging Safety Timers
7.3.6
USB On-The-Go (OTG)
7.3.6.1
Boost OTG Mode
7.3.7
Integrated 12-bit ADC for Monitoring
7.3.8
Status Outputs (INT , PG , STAT)
7.3.8.1
PG Pin Power Good Indicator
7.3.8.2
Charging Status Indicator (STAT)
7.3.8.3
Interrupt to Host (INT)
7.3.9
BATFET Control
7.3.9.1
Shutdown Mode
7.3.9.2
Ultra-Low Power Mode (ULPM)
7.3.9.3
System Power Reset
7.3.10
Protections
7.3.10.1
Voltage and Current Monitoring in Battery Only and HIZ Modes
7.3.10.1.1
Battery Overcurrent Protection
7.3.10.1.2
Battery Undervoltage Lockout
7.3.10.2
Voltage and Current Monitoring in Buck Mode
7.3.10.2.1
Input Overvoltage
7.3.10.2.2
System Overvoltage Protection (SYSOVP)
7.3.10.2.3
Forward Converter Cycle-by-Cycle Current Limit
7.3.10.2.4
System Short
7.3.10.2.5
Battery Overvoltage Protection (BATOVP)
7.3.10.2.6
Sleep and Poor Source Comparators
7.3.10.3
Voltage and Current Monitoring in Boost Mode
7.3.10.3.1
Boost Mode Overvoltage Protection
7.3.10.3.2
Boost Mode Duty Cycle Protection
7.3.10.3.3
Boost Mode PMID Undervoltage Protection
7.3.10.3.4
Boost Mode Battery Undervoltage
7.3.10.3.5
Boost Converter Cycle-by-Cycle Current Limit
7.3.10.3.6
Boost Mode SYS Short
7.3.10.4
Thermal Regulation and Thermal Shutdown
7.3.10.4.1
Thermal Protection in Buck Mode
7.3.10.4.2
Thermal Protection in Boost Mode
7.3.10.4.3
Thermal Protection in Battery-only Mode
7.4
Device Functional Modes
7.4.1
Host Mode and Default Mode
7.4.2
Register Bit Reset
7.5
Programming
7.5.1
Serial Interface
7.5.1.1
Data Validity
7.5.1.2
START and STOP Conditions
7.5.1.3
Byte Format
7.5.1.4
Acknowledge (ACK) and Not Acknowledge (NACK)
7.5.1.5
Target Address and Data Direction Bit
7.5.1.6
Single Write and Read
7.5.1.7
Multi-Write and Multi-Read
8
Register Maps
8.1
BQ25638 Registers
9
Application and Implementation
9.1
Application Information
9.2
Typical Application
9.2.1
Design Requirements
9.2.2
Detailed Design Procedure
9.2.2.1
Inductor Selection
9.2.2.2
Input Capacitor
9.2.2.3
Output Capacitor
9.2.3
Application Curves
9.3
Power Supply Recommendations
9.4
Layout
9.4.1
Layout Guidelines
9.4.2
Layout Example
10
Device and Documentation Support
10.1
Device Support
10.1.1
Third-Party Products Disclaimer
10.2
Documentation Support
10.2.1
Related Documentation
10.3
Receiving Notification of Documentation Updates
10.4
Support Resources
10.5
Trademarks
10.6
Electrostatic Discharge Caution
10.7
Glossary
11
Revision History
12
Mechanical, Packaging, and Orderable Information
PACKAGE OPTION ADDENDUM
12.1
Tape and Reel Information
12.2
Mechanical Data
Data Sheet
BQ25638
I
2
C Controlled, 5A, Maximum 18V Input, Charger With NVDC Power Path Management and USB OTG Boost Output