SLAAE47A May   2022  – August 2022 DAC11001A , DAC11001B

 

  1.   Abstract
  2.   Trademarks
  3. 1Introduction
  4. 2DAC Error Sources
    1. 2.1 Offset Error
    2. 2.2 Gain Error
    3. 2.3 Integral Non Linearity (INL)
    4. 2.4 Noise Sources
  5. 3Error Sources from Reference
    1. 3.1 Initial Accuracy
    2. 3.2 Temperature Drift
    3. 3.3 Load Regulation Error
    4. 3.4 Line Regulation Error
    5. 3.5 0.1 - 10 Hz Peak-to-Peak Noise
    6. 3.6 Example Using REF7025
  6. 4Error Sources from Inverting and Non-Inverting Gain Stage
    1. 4.1 Input Offset Voltage Error
    2. 4.2 Input Offset Voltage Drift Error
    3. 4.3 Power Supply Rejection Ratio (PSRR) Error
    4. 4.4 Open Loop Gain Error
    5. 4.5 Resistor Tolerance Error
  7. 5Example Calculation using DAC11001A
  8. 6Error Summary
  9. 7References
  10. 8Revision History

6 Error Summary

Total error for this DAC circuit topology can be calculated using root-sum-square method or worst-case error method. Assuming all the error sources are not correlated to each other, we can calculate the total error as follows.

Equation 16. Total Error = Vref Error2+DAC Error2 + Non Inverting Amp Error2+Inverting Amp Error2 +........
Table 6-1 Total Error Calculations
Error ContributionError in ppm
DAC11001A57.95
Voltage Reference (REF6025)525
Non Inverting Amplifier (OPA828)532.05
Inverting Amplifier (OPA828)303.66
Reference Buffer (Both inverting and non inverting stages)215.38
DAC output buffer (OPA828)76.2
Total840.65

As shown in Table 6-1, it is clear that the total error in the 20-bit DAC system is dominated by the reference amplifier and the buffer section. DAC11001A contributes approximately 4% of the total error in the system.

Figure 6-1 Error Distribution Pie Chart
Table 6-2 Design Featured Devices
Device Key featuresLink
DAC11001ADACx1001 20-Bit, 18-Bit, and 16-Bit, Low-Noise, Ultra-Low Harmonic Distortion, Fast Settling, High-Voltage Output, Digital-to-Analog Converters (DADAC11001A
OPA828OPA828 Low-Offset, Low-Drift, Low-Noise, 45-MHz, 36-V JFET-Input, RRO Operational AmplifierOPA828
REF6025REF60xx High-Precision Voltage Reference With Integrated ADC Drive Buffer REF6025