ACT8935
Rev 4, 17-Sep-13
TABLE OF CONTENTS
General Information.....................................................................................................................................p. 01
Functional Block Diagram............................................................................................................................p. 03
Ordering Information....................................................................................................................................p. 04
Pin Configuration .........................................................................................................................................p. 04
Pin Descriptions...........................................................................................................................................p. 05
Absolute Maximum Ratings.........................................................................................................................p. 07
I2C Interface Electrical Characteristics ........................................................................................................p. 08
Global Register Map....................................................................................................................................p. 09
Register and Bit Descriptions ......................................................................................................................p. 10
System Control Electrical Characteristics....................................................................................................p. 15
Step-Down DC/DC Electrical Characteristics..............................................................................................p. 16
Low-Noise LDO Electrical Characteristics...................................................................................................p. 17
ActivePathTM Charger Electrical Characteristics..........................................................................................p. 18
Typical Performance Characteristics...........................................................................................................p. 20
Application Information ................................................................................................................................p. 27
Interfacing with the SiRF PrimaTM/Atlas IVTM ...................................................................................p. 27
Control Signals.................................................................................................................................p. 28
Push-Button Control.........................................................................................................................p. 29
Control Sequences...........................................................................................................................p. 29
Functional Description .................................................................................................................................p. 33
I2C Interface .....................................................................................................................................p. 33
Voltage Monitor and Interrupt...........................................................................................................p. 33
Thermal Shutdown ...........................................................................................................................p. 34
Step-Down DC/DC Regulators ....................................................................................................................p. 35
General Description..........................................................................................................................p. 35
100% Duty Cycle Operation.............................................................................................................p. 35
Synchronous Rectification................................................................................................................p. 35
Soft-Start ..........................................................................................................................................p. 35
Compensation ..................................................................................................................................p. 35
Configuration Options.......................................................................................................................p. 35
OK[ ] and Output Fault Interrupt.......................................................................................................p. 36
PCB Layout Considerations.............................................................................................................p. 36
Low-Noise, Low-Dropout Linear Regulators................................................................................................p. 37
General Description..........................................................................................................................p. 37
Output Current Limit.........................................................................................................................p. 37
Compensation ..................................................................................................................................p. 37
Configuration Options.......................................................................................................................p. 37
OK[ ] and Output Fault Interrupt.......................................................................................................p. 37
PCB Layout Considerations.............................................................................................................p. 37
ActivePathTM Charger ..................................................................................................................................p. 39
General Description..........................................................................................................................p. 39
ActivePath Architecture....................................................................................................................p. 39
System Configuration Optimization..................................................................................................p. 39
Input Protection ................................................................................................................................p. 39
Battery Management........................................................................................................................p. 39
Charge Current Programming..........................................................................................................p. 40
Charger Input Interrupts ...................................................................................................................p. 40
Charge-Control State Machine.........................................................................................................p. 42
State Machine Interrupts..................................................................................................................p. 42
Thermal Regulation..........................................................................................................................p. 43
Charge Safety Timers ......................................................................................................................p. 43
Charge Timer Interrupts ...................................................................................................................p. 43
Charge Status Indicator....................................................................................................................p. 43
Reverse-Current Protection .............................................................................................................p. 43
Battery Temperature Monitoring ......................................................................................................p. 43
Battery Temperature Interrupts........................................................................................................p. 44
TQFN55-40 Package Outline and Dimensions ...........................................................................................p. 45
Innovative PowerTM
- 2 -
www.active-semi.com
Active-Semi Proprietary―For Authorized Recipients and Customers
ActivePMUTM and ActivePathTM are trademarks of Active-Semi.
Copyright © 2013 Active-Semi, Inc.