SLUS900E December   2008  – August 2015

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 I2C Timing Requirements
    7. 6.7 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 IRQ Function
      2. 7.3.2 VBACK Switchover
      3. 7.3.3 Trickle Charge
    4. 7.4 Device Functional Modes
    5. 7.5 Programming
      1. 7.5.1 I2C Serial Interface
    6. 7.6 Register Maps
      1. 7.6.1 I2C Read After Backup Mode
      2. 7.6.2 Normal Register Descriptions
        1. 7.6.2.1  SECONDS Register (address = 0x00) [reset = 0XXXXXXb]
        2. 7.6.2.2  MINUTES Register (address = 0x01) [reset = 1XXXXXXb]
        3. 7.6.2.3  CENT_HOURS Register (address = 0x02) [reset = XXXXXXXXb]
        4. 7.6.2.4  DAY Register (address = 0x03) [reset = 00000XXXb]
        5. 7.6.2.5  DATE Register (address = 0x04) [reset = 00XXXXXXb]
        6. 7.6.2.6  MONTH Register (address = 0x05) [reset = 000XXXXXb]
        7. 7.6.2.7  YEARS Register (address = 0x06) [reset = XXXXXXXXb]
        8. 7.6.2.8  CAL_CFG1 Register (address = 0x07) [reset = 10000000b]
        9. 7.6.2.9  TCH2 Register (address = 0x08) [reset = 10010000b]
        10. 7.6.2.10 CFG2 Register (address = 0x09) [reset = 10101010b]
      3. 7.6.3 Special Function Registers
        1. 7.6.3.1 SF KEY 1 Register (address = 0x20) [reset = 00000000b]
        2. 7.6.3.2 SF KEY 2 Register (address = 0x21) [reset = 00000000b]
        3. 7.6.3.3 SFR Register (address = 0x22) [reset = 00000000b]
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Reading From a Register
        2. 8.2.2.2 Leap Year Compensation
        3. 8.2.2.3 Utilizing the Backup Supply
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
    2. 11.2 Community Resources
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

1 Features

  • Automatic Switchover to Backup Supply
  • I2C Interface Supports Serial Clock up to 400 kHz
  • Uses 32.768-kHz Crystal With –63-ppm to
    +126-ppm Adjustment
  • Integrated Oscillator-Fail Detection
  • 8-Pin SOIC Package
  • –40°C to 85°C Ambient Operating Temperature

2 Applications

  • General Consumer Electronics

3 Description

The bq32000 device is a compatible replacement for industry standard real-time clocks.

The bq32000 features an automatic backup supply with integrated trickle charger. The backup supply can be implemented using a capacitor or non-rechargeable battery. The bq32000 has a programmable calibration adjustment from –63 ppm to +126 ppm. The bq32000 registers include an OF (oscillator fail) flag indicating the status of the RTC oscillator, as well as a STOP bit that allows the host processor to disable the oscillator. The time registers are normally updated once per second, and all the registers are updated at the same time to prevent a timekeeping glitch. The bq32000 includes automatic leap-year compensation.

Device Information(1)

PART NUMBER PACKAGE BODY SIZE (NOM)
bq32000 SOIC (8) 4.90 mm x 3.91 mm
  1. For all available packages, see the orderable addendum at the end of the data sheet.

Simplified Schematic

bq32000 real_time_clock_slus900.gif