SNVS481M November   2006  – December 2015 LP3910

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Device Comparison Tables
  6. 6 Pin Configuration and Functions
  7. 7 Specifications
    1. 7.1  Absolute Maximum Ratings
    2. 7.2  ESD Ratings
    3. 7.3  Recommended Operating Conditions
    4. 7.4  Thermal Information
    5. 7.5  Electrical Characteristics
    6. 7.6  Electrical Characteristics: I2C Interface
    7. 7.7  Electrical Characteristics: Li-Ion Battery Charger
    8. 7.8  Detection and Timing
    9. 7.9  Output Electrical Characteristics: CHG, STAT
    10. 7.10 Output Electrical Characteristics: NRST, IRQB, ONSTAT
    11. 7.11 Input Electrical Characteristics: USBSUSP, USBISEL
    12. 7.12 Input Electrical Characteristics: POWERACK, ONOFF, LDO2EN, BUCK1EN
    13. 7.13 Electrical Characteristics: LDO1 Low Dropout Linear Regulators
    14. 7.14 Electrical Characteristics: LDO2 Low Dropout Linear Regulator
    15. 7.15 Electrical Characteristics: Buck1 Converter
    16. 7.16 Electrical Characteristics: Buck2 Converter
    17. 7.17 Electrical Characteristics: Buck-Boost
    18. 7.18 Electrical Characteristics: ADC
    19. 7.19 I2C Timing Requirements
    20. 7.20 USB Timing Requirements
    21. 7.21 Typical Characteristics
      1. 7.21.1 Battery-Charger Characteristics
      2. 7.21.2 LDO Characteristics
      3. 7.21.3 Buck Characteristics
      4. 7.21.4 Buck-Boost Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
      1. 8.1.1 Two Buck Converters
      2. 8.1.2 Buck-Boost Converter
      3. 8.1.3 LDO Regulators
      4. 8.1.4 Battery Charger
      5. 8.1.5 ADC
      6. 8.1.6 Supply Specification
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Buck1, Buck2: Synchronous Step-Down Magnetic DC-DC Converters
        1. 8.3.1.1 Buck1, Buck2 Operation
        2. 8.3.1.2 Circuit Operation Description
        3. 8.3.1.3 PWM Operation
        4. 8.3.1.4 Internal Synchronous Rectification
        5. 8.3.1.5 Current Limiting
        6. 8.3.1.6 PFM Operation
      2. 8.3.2  Buck-Boost: Synchronous Buck-Boost Magnetic DC-DC Converter
      3. 8.3.3  Linear Low Dropout Regulators (LDOs)
        1. 8.3.3.1 No-Load Stability
      4. 8.3.4  Li-Ion Linear Charger
        1. 8.3.4.1 Charger Architecture
        2. 8.3.4.2 Charge Status Indication
        3. 8.3.4.3 Thermal Charger Power FET Regulation
        4. 8.3.4.4 Battery Charger Operating Modes
          1. 8.3.4.4.1 Pre-Qualification Mode
          2. 8.3.4.4.2 Full-Rate Charging Mode
          3. 8.3.4.4.3 Constant-Voltage (CV) Charging Mode
          4. 8.3.4.4.4 Top-Off Charging Mode
          5. 8.3.4.4.5 Charge Cycle Complete
        5. 8.3.4.5 Battery Temperature Monitoring (TS Pin)
        6. 8.3.4.6 Disabling Charger
        7. 8.3.4.7 Safety Timer
        8. 8.3.4.8 Charging Maintenance
      5. 8.3.5  ADC
        1. 8.3.5.1 Battery Voltage Measurement
        2. 8.3.5.2 Battery Charge Current Measurement
        3. 8.3.5.3 External General-Purpose Sources
      6. 8.3.6  Interrupt Request Output
        1. 8.3.6.1 Interrupts and Standby Mode
        2. 8.3.6.2 Interrupt Sources
      7. 8.3.7  Power-On-Reset
      8. 8.3.8  Thermal Shutdown and Thermal Alarm
      9. 8.3.9  NRST Pin
      10. 8.3.10 Operation Without I2C Interface
      11. 8.3.11 I2C Master Power Concern
      12. 8.3.12 System Operation When the Load Current Exceeds the USB or Adapter Current Limit
      13. 8.3.13 Power Routing
      14. 8.3.14 Battery Monitor
      15. 8.3.15 External Power and Battery Detection
      16. 8.3.16 USB Suspend Mode
      17. 8.3.17 Setting the USB Current Limit
      18. 8.3.18 Control Registers
    4. 8.4 Device Functional Modes
      1. 8.4.1 State Machine Definitions
        1. 8.4.1.1 Power-Off Mode
        2. 8.4.1.2 Standby Mode
        3. 8.4.1.3 Active Mode
      2. 8.4.2 Mode Sequencing
        1. 8.4.2.1 Power-On, Power-Off Sequencing
        2. 8.4.2.2 Power-On Timing
        3. 8.4.2.3 Power-Off Timing
        4. 8.4.2.4 Transitioning From Standby to Active Mode (Power Up) Battery Power Present Only
        5. 8.4.2.5 Transitioning From Active Mode to Standby Mode
          1. 8.4.2.5.1 External Event Triggers the Transition From Active to Standby Mode
          2. 8.4.2.5.2 Transition From Active to Standby Mode Due to Expiring POWERACK Deadline
          3. 8.4.2.5.3 Transition From Charger Standby Mode to Either Active or Standby Mode
    5. 8.5 Programming
      1. 8.5.1 I2C-Compatible Serial Interface
        1. 8.5.1.1 I2C Signals
        2. 8.5.1.2 I2C Data Validity
        3. 8.5.1.3 I2C Start and Stop Conditions
        4. 8.5.1.4 Transferring Data
        5. 8.5.1.5 Register Write Cycle
        6. 8.5.1.6 Register Read Cycle
        7. 8.5.1.7 Multi-Byte I2C Command Sequence
    6. 8.6 Register Maps
      1. 8.6.1  LDO1 Control Register
      2. 8.6.2  BATTLOW Register (04)H Battery Low Alarm Register
      3. 8.6.3  PON Register (00)H Power-On Event Register
      4. 8.6.4  CHCTL Register (01)H Charger Control Register
      5. 8.6.5  CHSPV Register (02)H Charger Supervisor Register
      6. 8.6.6  ILIMIT Register (03)H Current Limit Register
      7. 8.6.7  ADCC Register (0a)H ADC Control Register
      8. 8.6.8  ADCD Register (0b)H ADC Output Data Register
      9. 8.6.9  IMR Register (0c)H Interrupt Mask Register
      10. 8.6.10 IRQ Register (0d)H Interrupt Request Register
      11. 8.6.11 LDO1 Control Register (08)H
      12. 8.6.12 LDO2 Control Register
      13. 8.6.13 Buck1, Buck2 Control Registers and BUCK1EN Pin
      14. 8.6.14 Buck-Boost Control Register
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Inductors for Buck1, Buck2 and Buck-Boost
          1. 9.2.2.1.1 Method 1
          2. 9.2.2.1.2 Method 2
        2. 9.2.2.2 External Capacitors
          1. 9.2.2.2.1 LDO Capacitor Selection
            1. 9.2.2.2.1.1 Input Capacitor
            2. 9.2.2.2.1.2 Output Capacitor
            3. 9.2.2.2.1.3 Capacitor Characteristics
            4. 9.2.2.2.1.4 Noise Bypass Capacitors for VREFH Pin
          2. 9.2.2.2.2 Buck1, Buck2 and Buck-Boost Capacitor Selection
            1. 9.2.2.2.2.1 Input Capacitor Selection for Buck1, Buck2 and Buck-Boost
            2. 9.2.2.2.2.2 Output Capacitor Selection for Buck1, Buck2 and Buck-Boost
        3. 9.2.2.3 Schottky Diode on Charger Input CHG_IN
        4. 9.2.2.4 Resistors
          1. 9.2.2.4.1 Battery Thermistor
          2. 9.2.2.4.2 I2C Pullup Resistors
          3. 9.2.2.4.3 RIREF Resistor
          4. 9.2.2.4.4 RISENSE Resistor
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
      1. 11.1.1 LDO Regulators
      2. 11.1.2 Buck and Buck-Boost Regulators
    2. 11.2 Layout Example
    3. 11.3 Thermal Performance of the WQFN Package
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Third-Party Products Disclaimer
    2. 12.2 Documentation Support
      1. 12.2.1 Related Documentation
    3. 12.3 Community Resources
    4. 12.4 Trademarks
    5. 12.5 Electrostatic Discharge Caution
    6. 12.6 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

5 Device Comparison Tables

Table 1. Device Default Voltage Options

ORDER NUMBER LDO1 LDO2 BUCK1 BUCK2 BUCK-BOOST ICHRG
LP3910SQ-AA 2 V 3.3 V 1.2 V 3.3 V 3.3 V 100 mA
LP3910SQX-AA 2 V 3.3 V 1.2 V 3.3 V 3.3 V 100 mA
LP3910SQ-AK 2.5 V 3 V 1.6 V 1.8 V 3.3 V 100 mA
LP3910SQX-AK 2.5 V 3 V 1.6 V 1.8 V 3.3 V 100 mA
LP3910SQ-AM 3.3 V 3.3 V 1.5 V 1.8 V 3.3 V 100 mA
LP3910SQX-AM 3.3 V 3.3 V 1.5 V 1.8 V 3.3 V 100 mA
LP3910SQ-AN 1.2 V 2.5 V 1 V 1.8 V 3.3 V 1000 mA
LP3910SQX-AN 1.2 V 2.5 V 1 V 1.8 V 3.3 V 1000 mA

Table 2. Device Option Parameters for AP Option

SYMBOL DESCRIPTION VALUE
LDO1 Default LDO1 2.8 V
LDO2 Default LDO2 1.5 V
Buck1 Default Buck1 1.45 V
Buck2 Default Buck2 1.8 V
Buck-Boost Default Buck-Boost 3.3 V
ICHRG Default charge current 100 mA
T1 Turnon delay for LDO1 and LDO2 6 ms
T2 Turnon delay for Buck1 3 ms
T3 Turnon delay for Buck2 1 ms
T4 Turnon delay for Buck-Boost 0 ms
T5 Turnon delay for NRST 10 ms
T1 Turnoff delay for LDO1 and LDO2 10 ms
T2 Turnoff delay for Buck1 10 ms
T3 Turnoff delay for Buck2 10 ms
T4 Turnoff delay for Buck-Boost 10 ms
T5 Turnoff delay for NRST 3 ms
VBATTLOW battery low threshold 2.5 V
VFULLRATE Full-rate threshold 2.55 V
ILED Default LED current 2 V

The following options are programmed for the LP3910. The system designer that needs specific options is advised to contact the local Texas Instruments sales office.

Table 3. Factory Programmable Options

FACTORY PROGRAMMABLE OPTIONS DEFAULT VALUE (AA)
LDO1 output voltage after power up 2 V
LDO2 output voltage after power up 3.3 V
BUCK1 output voltage after power up 1.2 V
BUCK2 output voltage after power up 3.3 V
BUCK-BOOST power voltage after power up 3.3 V
Battery low threshold 2.9 V
Delay for LDO1 and LDO2 5 ms
Delay for BUCK1 15 ms
Delay for BUCK2 20 ms
Delay for BUCK-BOOST 25 ms
Delay for NRST 60 ms
Default full-rate charge current 100 mA
EOC default 0.1C
VTERM default 4.2 V
ONOFF edge/level Level
ONOFF polarity Positive
BUCK1 enable polarity Positive
LDO2 enable polarity Positive
Ignore ten-hour timer No
LED default current 10 mA
Buck-boost 500-mA output current No
Thermistor 10 k/100 k 100 k

The I2C Chip ID address is offered as a metal mask option. The current value equals 60 hex.