INFICON Spot CDS550D - Manual (Page 11)

Research & Development
SPOT CDS500D & CDS550D OEM Sensor SPI-Interface Specification_V1.1 Page 11 of 14
Christian Berg, T based on Felix Mullis, TL Created 11/10/2014 2:36:00 PM
5.2 SPI Timing
5.2.1 Introduction
This chapter describes the principle time-behavior of the SPOT CDS5xxD sensors. This is a generic
timing example. The actual time-behavior is described in section 2.4.Timing Specifications.
5.2.2 Timing
5.2.2.1 Overview
Figure 2: Timing Overview
Figure 2 shows the timing overview.
•
Ch 1 (yellow) depicts the signal directly at the sensor
•
Ch 2 (blue) equals the RDY (Ready) signal
The SPOT CDS5xxD sensor is configured to run “free” meaning that it
1. starts a measurement cycle consisting of 16 single measurements
2. computes the average of this 16 measurements
3. activates the RDY-signal
4. waits until the total measurement cycle time has elapsed
5. jumps back to step 1.
The corresponding timing is explained in more details in the following chapters.
Total measu-
rement cycle single measu-
rement cycle readout time
window