ZHCSKJ2A November   2019  – April 2020 DAC60502 , DAC70502 , DAC80502

PRODUCTION DATA.  

  1. 1 特性
  2. 2 应用
  3. 3 说明
    1.     Device Images
      1.      功能方框图
  4. 4 修订历史记录
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and Functions
    1.     Pin 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  Timing Requirements : SPI Mode
    7. 7.7  Timing Requirements : I2C Standard Mode
    8. 7.8  Timing Requirements : I2C Fast Mode
    9. 7.9  Timing Requirements : I2C Fast-Mode Plus
    10. 7.10 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Digital-to-Analog Converter (DAC) Architecture
        1. 8.3.1.1 DAC Transfer Function
        2. 8.3.1.2 DAC Register Structure
        3. 8.3.1.3 Output Amplifier
      2. 8.3.2 Internal Reference
        1. 8.3.2.1 Solder Heat Reflow
      3. 8.3.3 Power-On Reset (POR)
      4. 8.3.4 Software Reset
    4. 8.4 Device Functional Modes
      1. 8.4.1 Power-Down Mode
    5. 8.5 Programming
      1. 8.5.1 Serial Interface
        1. 8.5.1.1 SPI Mode
          1. 8.5.1.1.1 SYNC Interrupt
        2. 8.5.1.2 I2C Mode
          1. 8.5.1.2.1 F/S Mode Protocol
          2. 8.5.1.2.2 DACx0502 I2C Update Sequence
            1. 8.5.1.2.2.1 DACx0502 Address Byte
            2. 8.5.1.2.2.2 DACx0502 Command Byte
            3. 8.5.1.2.2.3 DACx0502 Data Byte (MSDB and LSDB)
          3. 8.5.1.2.3 DACx0502 I2C Read Sequence
    6. 8.6 Register Maps
      1. 8.6.1 Registers
        1. 8.6.1.1 NOOP Register (offset = 0h) [reset = 0000h]
          1. Table 9. NOOP Register Field Descriptions
        2. 8.6.1.2 DEVID Register (offset = 1h) [reset = 0214h for DAC80502, 1214h for DAC70502, 2214h for DAC60502]
          1. Table 10. DEVID Register Field Descriptions
        3. 8.6.1.3 SYNC Register (offset = 2h) [reset = 0300h]
          1. Table 11. SYNC Register Field Descriptions
        4. 8.6.1.4 CONFIG Register (offset = 3h) [reset = 0000h]
          1. Table 12. CONFIG Register Field Descriptions
        5. 8.6.1.5 GAIN Register (offset = 4h) [reset = 0003h]
          1. Table 13. GAIN Register Field Descriptions
        6. 8.6.1.6 TRIGGER Register (offset = 5h) [reset = 0000h]
          1. Table 14. TRIGGER Register Field Descriptions
        7. 8.6.1.7 BRDCAST Register (offset = 6h) [reset = 0000h for RSTSEL = 0, or reset = 8000h for RSTSEL = 1]
          1. Table 15. BRDCAST Register Field Descriptions
        8. 8.6.1.8 STATUS Register (offset = 7h) [reset = 0000h]
          1. Table 16. STATUS Register Field Descriptions
        9. 8.6.1.9 DAC-n Register (offset = 8h–9h) [reset = 0000h for RSTSEL = 0, or reset = 8000h for RSTSEL = 1]
          1. Table 17. DAC-A Data Register Field Descriptions (8h)
          2. Table 18. DAC-B Data Register Field Descriptions (9h)
  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
      3. 9.2.3 Application Curves
    3. 9.3 System Examples
      1. 9.3.1 SPI Connection to a Processor
      2. 9.3.2 I2C Interface Connection to a Processor
    4. 9.4 What To Do and What Not To Do
      1. 9.4.1 What To Do
      2. 9.4.2 What Not To Do
    5. 9.5 Initialization Setup
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12器件和文档支持
    1. 12.1 文档支持
      1. 12.1.1 相关文档
    2. 12.2 相关链接
    3. 12.3 接收文档更新通知
    4. 12.4 支持资源
    5. 12.5 商标
    6. 12.6 静电放电警告
    7. 12.7 Glossary
  13. 13机械、封装和可订购信息

封装选项

机械数据 (封装 | 引脚)
散热焊盘机械数据 (封装 | 引脚)
订购信息

8.3.2 Internal Reference

The DAx0502 family of devices includes a 2.5-V precision band-gap reference enabled by default. Operation from an external reference is supported by disabling the internal reference in the REF_PWDWN bit (address 3h). The internal reference is externally available at the VREFIO pin and sources up to 5 mA. For noise filtering, use a minimum 150-nF capacitor between the reference output and AGND.

The reference voltage to the device, either from the internal reference or an external one, can be divided by a factor of two by setting the REF-DIV bit (address 4h) to 1. The REF-DIV bit provides additional flexibility in setting the full-scale output range of the DAC output. Make sure to configure REF-DIV so that there is sufficient headroom from VDD to the DAC operating reference voltage, VREFIO (see Equation 1). See the Recommended Operating Conditions for more information.

Improper configuration of the reference divider triggers a reference alarm condition. In this case, the reference buffer is shut down, and all the DAC outputs go to 0 V. The DAC data registers are unaffected by the alarm condition, and thus enable the DAC output to return to normal operation after the reference divider is configured correctly.