RayTek MI Miniature Infrared Sensor - Manual (Page 37)

Installation
MI 29
Hold: This mode acts as external generated hold function. A
transition at the input FTC3 from logical high level toward logical
low level will transfer the current temperature toward the output.
This temperature will be written to the output until a new transition
from high to low occurs at the input FTC3.
Figure 19: FTC3 for Holding the Output Temperature
object temperature
output temperature
Trigger
Temp
Time