SBAA631 January   2025 DAC80508 , INA592 , XTR111 , XTR300 , XTR305

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Analog Output Module Specification
  6. 3Analog Output Module Structure
  7. 4Multi-Channel Output Architectures
    1. 4.1 Fully Integrated DAC Architecture
    2. 4.2 Low Voltage DAC Plus an Output Buffer
    3. 4.3 Track and Hold Multiplexed Output
  8. 5Single-Channel Output Architectures
    1. 5.1 Fully Integrated DAC
    2. 5.2 Low-Voltage DAC Plus an Output Buffer
    3. 5.3 Pulse-Width Modulation Plus a Buffer
  9. 6Output Buffers
    1. 6.1 Unidirectional Current Buffer
    2. 6.2 Bidirectional Current Buffer
    3. 6.3 Voltage Buffer
    4. 6.4 Combined Voltage or Current Buffer
  10. 7Summary
  11. 8References

5.3 Pulse-Width Modulation Plus a Buffer

Pulse-Width Modulation (PWM DAC) is a special architecture used when the stand-alone DAC is to be avoided, and MCU is available in the system. The PWM can be converted to an analog voltage signal using a low-pass filter. Advanced techniques can be used to reach 16b of resolution, and relatively fast output settling time as described in Designing high-performance PWM DACs for field transmitters, and High-Performance 16-bit PWM to 4- to 20-mA DAC for Field Transmitters.

2-Path PWM-Based DAC Block DiagramFigure 5-2 2-Path PWM-Based DAC Block Diagram