SLAS464C December   2006  – January 2018 DAC8560

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Functional Block Diagram
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin 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  Timing Requirements
    7. 6.7  Typical Characteristics: Internal Reference
    8. 6.8  Typical Characteristics: DAC at VDD = 5 V
    9. 6.9  Typical Characteristics: DAC at VDD = 3.6 V
    10. 6.10 Typical Characteristics: DAC at VDD = 2.7 V
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Digital-to-Analog Converter (DAC)
      2. 7.3.2 Resistor String
      3. 7.3.3 Output Amplifier
      4. 7.3.4 DAC Noise Performance
      5. 7.3.5 Internal Reference
        1. 7.3.5.1 Enable/Disable Internal Reference
        2. 7.3.5.2 Internal Reference Load
          1. 7.3.5.2.1 Supply Voltage
          2. 7.3.5.2.2 Temperature Drift
          3. 7.3.5.2.3 Noise Performance
          4. 7.3.5.2.4 Load Regulation
          5. 7.3.5.2.5 Long-Term Stability
          6. 7.3.5.2.6 Thermal Hysteresis
    4. 7.4 Device Functional Modes
      1. 7.4.1 Power-Down Modes
    5. 7.5 Programming
      1. 7.5.1 Serial Interface
      2. 7.5.2 Input Shift Register
      3. 7.5.3 SYNC Interrupt
      4. 7.5.4 Power-On Reset
    6. 7.6 Register Maps
      1. 7.6.1 Write Sequence for Disabling the DAC8560 Internal Reference
        1. Table 1. Write Sequence for Disabling the DAC8560 Internal Reference
      2. 7.6.2 Enabling the DAC8560 Internal Reference (Write Sequence 1 of 2)
        1. Table 2. Enabling the DAC8560 Internal Reference (Write Sequence 1 of 2)
      3. 7.6.3 Enabling the DAC8560 Internal Reference (Write Sequence 2 of 2)
        1. Table 3. Enabling the DAC8560 Internal Reference (Write Sequence 2 of 2)
      4. 7.6.4 DAC8560 Data Input Register Format
        1. Table 4. DAC8560 Data Input Register Format
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure or Bipolar Operation > ±VREF
        1. 8.2.2.1 Bipolar Operation Greater Than ±VREF
          1. 8.2.2.1.1 Passive Component Selection
          2. 8.2.2.1.2 Amplifier Selection
        2. 8.2.2.2 Microprocessor Interfacing
          1. 8.2.2.2.1 DAC8560 to 8051 Interface
          2. 8.2.2.2.2 DAC8560 to Microwire Interface
          3. 8.2.2.2.3 DAC8560 to 68HC11 Interface
      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 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Community Resource
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

7.4.1 Power-Down Modes

The DAC8560 supports four separate modes of operation. These modes are programmable by setting two bits (PD1 and PD0) in the control register. Table 1 shows how to control the operating mode with data bits PD1 (DB17) and PD0 (DB16).

Table 1. Operating Modes

PD1 (DB17) PD0 (DB16) OPERATING MODE
0 0 Normal operation
0 1 Power-down 1 kΩ to GND
1 0 Power-down 100 kΩ to GND
1 1 Power-down High-Z

When both bits are set to 0, the device works normally with its typical current consumption of 530 μA at 5.5 V. However, for the three power-down modes, the supply current falls to 1.2 μA at 5.5 V (0.7 μA at 3.6 V). Not only does the supply current fall, but the output stage is also internally switched from the output of the amplifier to a resistor network of known values.

The advantage of this switching is that the output impedance of the device is known while it is in power-down mode. As shown in Table 1, there are three different power-down options. VOUT can be connected internally to GND through a 1-kΩ resistor, a 100-kΩ resistor, or open-circuited (High-Z). The output stage is shown in Figure 68.

DAC8560 too_out_stage_las464.gifFigure 68. Output Stage During Power Down

All analog circuitry is shut down when the power-down mode is activated. However, the contents of the DAC register are unaffected when in power down. The time to exit power down is typically 2.5 μs for VDD = 5 V, and 5 μs for VDD = 3 V. See the Typical Characteristics: DAC at VDD = 5 V for more information.