Systems that rely on LVDS input to the LMH13000 as the start reference point for time-of-flight calculations require accurate calibration of the prorogation delay from LVDS to IOUT. Propagation delay varies with temperature as a result of changes in device behavior, thus creating timing mismatches in sensitive systems.

Measurement and Calibration Approach:

1. Measure propagation delay values at three key temperature points: low (-40°C), ambient (25°C), and high (125°C).
2. A second-order polynomial fit is applied to the delay versus temperature curve using linear regression techniques.
3. Use this polynomial equation to predict delay values at intermediate temperatures.
4. See Figure 5-30 for error in delay estimation. The graph shows the difference between actual measured delay versus predicted delay.

This calibration technique enables effective compensation for temperature-induced propagation delay shifts. Applying the polynomial correction maintains consistent timing behavior across operating conditions.