SBAS793A November   2019  – April 2020 DAC60502 , DAC70502 , DAC80502

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Functional Block Diagram
  4. 4 Revision History
  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. 12Device and Documentation Support
    1. 12.1 Documentation Support
      1. 12.1.1 Related Documentation
    2. 12.2 Related Links
    3. 12.3 Receiving Notification of Documentation Updates
    4. 12.4 Support Resources
    5. 12.5 Trademarks
    6. 12.6 Electrostatic Discharge Caution
    7. 12.7 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

9.5 Initialization Setup

The DACx0502 requires a simple software initialization process based on the interface, power supply, and reference selection. The initialization steps are as follows:

  1. When using an external reference, disable the internal reference.
  2. Divide the reference by two when the reference voltage exceeds the headroom required from VDD. For example, when using 3.3-V VDD and the internal reference of 2.5 V, the DAC outputs are disabled unless the reference is divided by two.
  3. Set the output gain.
  4. Write to the DAC register.

The following text shows the pseudocode to get started with the DACx0502:

//SPI Settings
//Mode: Mode-1 (CPOL: 0, CPHA: 1)
//CS Type: Active Low, Per Packet
//Frame length: 24
//SYNTAX: <WRITE REGISTER (HEX ADDRESS)>, <HEX DATA>
//Disable internal reference (only in case of external reference)
WRITE CONFIG (0x03), 0x0100
//Select REFDIV=1 (reference divided by 2) and GAIN=1 (gain at both the DAC outputs is 2)
WRITE GAIN (0x04), 0x0103
//Write mid-code to DACA
WRITE DAC-A (0x08), 0x7FFF
//Write Full-code to DACB
WRITE DAC-B (0x09), 0xFFFF