SLYT847 May   2024 DAC161S997 , DAC8551 , TVS3301

 

  1.   1
  2. 1 Introduction
  3. 2 4mA to 20mA transmitter basics
  4. 3 4mA to 20mA transmitter design aspects
  5. 4 Design performance metrics
  6. 5 Transmitter circuit implementations
  7. 6 Dedicated loop converter
  8. 7 Loop transmitter device
  9. 8 MCU integrated DAC
  10. 9 PWM-based DAC
  11. 10Stand-alone low power DAC
  12. 11Implementations Comparison
  13. 12Conclusion
  14. 13Related websites

8 MCU integrated DAC

Cost-sensitive applications can employ an MCU with analog resources. The MSPM0G MCU enables a transmitter stage implementation including an integrated 12-bit DAC, internal reference and output amplifier. An LDO is the only external device needed, as shown in Figure 6. Given the implementation of analog functions on the MCU’s digital process, they have relatively higher power consumption compared to their dedicated analog device counterparts. This approach is attractive for applications that require 11 bits of effective resolution at a very low cost. Using the VREF– pin as an internal reference negative pin instead of ground can improve performance. Separating the VREF– pin isolates digital noise from the analog reference.

Two-wire 4mA to 20mA transmitter implemented using the MSPM0G. Figure 6 Two-wire 4mA to 20mA transmitter implemented using the MSPM0G.