SLASEH2A November   2020  – May 2021 DAC61404 , DAC81404

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Device Comparison Table
  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  Timing Requirements: Write, IOVDD: 1.7 V to 2.7 V
    7. 7.7  Timing Requirements: Write, IOVDD: 2.7 V to 5.5 V
    8. 7.8  Timing Requirements: Read and Daisy Chain, FSDO = 0, IOVDD: 1.7 V to 2.7 V
    9. 7.9  Timing Requirements: Read and Daisy Chain, FSDO = 1, IOVDD: 1.7 V to 2.7 V
    10. 7.10 Timing Requirements: Read and Daisy Chain, FSDO = 0, IOVDD: 2.7 V to 5.5 V
    11. 7.11 Timing Requirements: Read and Daisy Chain, FSDO = 1, IOVDD: 2.7 V to 5.5 V
    12. 7.12 Timing Diagrams
    13. 7.13 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 R-2R Ladder DAC
      2. 8.3.2 Programmable-Gain Output Buffer
        1. 8.3.2.1 Sense Pins
      3. 8.3.3 DAC Register Structure
        1. 8.3.3.1 DAC Output Update
          1. 8.3.3.1.1 Synchronous Update
          2. 8.3.3.1.2 Asynchronous Update
        2. 8.3.3.2 Broadcast DAC Register
        3. 8.3.3.3 Clear DAC Operation
      4. 8.3.4 Internal Reference
      5. 8.3.5 Power-On Reset (POR)
        1. 8.3.5.1 Hardware Reset
        2. 8.3.5.2 Software Reset
      6. 8.3.6 Thermal Alarm
    4. 8.4 Device Functional Modes
      1. 8.4.1 Power-Down Mode
    5. 8.5 Programming
      1. 8.5.1 Stand-Alone Operation
      2. 8.5.2 Daisy-Chain Operation
      3. 8.5.3 Frame Error Checking
    6. 8.6 Register Map
      1. 8.6.1  NOP Register (address = 00h) [reset = 0000h]
      2. 8.6.2  DEVICEID Register (address = 01h) [reset = 0A60h or 0920h]
      3. 8.6.3  STATUS Register (address = 02h) [reset = 0000h]
      4. 8.6.4  SPICONFIG Register (address = 03h) [reset = 0AA4h]
      5. 8.6.5  GENCONFIG Register (address = 04h) [reset = 4000h]
      6. 8.6.6  BRDCONFIG Register (address = 05h) [reset = 000Fh]
      7. 8.6.7  SYNCCONFIG Register (address = 06h) [reset = 0000h]
      8. 8.6.8  DACPWDWN Register (address = 09h) [reset = FFFFh]
      9. 8.6.9  DACRANGE Register (address = 0Ah) [reset = 0000h]
      10. 8.6.10 TRIGGER Register (address = 0Eh) [reset = 0000h]
      11. 8.6.11 BRDCAST Register (address = 0Fh) [reset = 0000h]
      12. 8.6.12 DACn Register (address = 10h to 13h) [reset = 0000h]
  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
  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 Receiving Notification of Documentation Updates
    3. 12.3 Support Resources
    4. 12.4 Trademarks
    5. 12.5 Electrostatic Discharge Caution
    6. 12.6 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

8.3.2 Programmable-Gain Output Buffer

The voltage output stage as conceptualized in Figure 8-3 provides the voltage output according to the DAC code and the output range setting.

GUID-20201106-CA0I-MMHP-VBXR-GSVZLLCQK14V-low.svg Figure 8-3 Voltage Output Buffer

For unipolar output mode, the output range can be programmed as:

  • 0 V to 5 V
  • 0 V to 10 V
  • 0 V to 20 V
  • 0 V to 40 V

For bipolar output mode, the output reange can be programmed as:

  • ±5 V
  • ±10 V
  • ±20 V

In addition, 20% overrange is available on all ranges except for 0 V to 40 V and ±20 V.

The input data are written to the individual DAC data registers in straight-binary format for all output ranges. The output voltage (VOUTX) can be expressed as Equation 1 and Equation 2.

For unipolar output mode

Equation 1. GUID-AD314581-DBAC-46F1-9369-6EB7F253E484-low.gif

For bipolar output mode

Equation 2. GUID-AFC0ECDB-7AB4-44FA-B5B3-3CF24CBD4A34-low.gif
where:
  • CODE is the decimal equivalent of the binary code loaded to the DAC data register.
  • N is the DAC resolution in bits.
  • VREFIO is the reference voltage (internal or external).
  • GAIN is the gain factor assigned to each output voltage output range as shown in Table 8-1.
Table 8-1 Voltage Output Range vs Gain Setting
MODE VOLTAGE OUTPUT RANGE GAIN
Unipolar 5 V 2.0
6 V (20% overrange) 2.4
10 V 4.0
12 V (20% overrange) 4.8
20 V 8.0
24 V (20% overrange) 9.6
40 V 16.0
Bipolar ±5 V 4.0
±6 V (20% overrange) 4.8
±10 V 8.0
±12 V (20% overrange) 9.6
±20 V 16.0

The output amplifiers can drive up to ±15 mA with 1.5-V supply headroom while maintaining the specified TUE specification for the device. The output stage has short-circuit current protection that limits the output current to 40 mA. The device is able to drive capacitive loads up to 1 µF. For loads greater than 2 nF, an external compensation capacitor must be connected between the CCOMPx and OUTx pins to keep the output voltage stable, but at the expense of reduced bandwidth and increased settling time.