Vaisala LT31 - Figure 21 Block Diagram LTL212; Figure 22 Measurement Head CPU LTC112; Measurement Head CPU LTC112

Chapter 3 ______________________________________________________ Functional Description
VAISALA _______________________________________________________________________ 53
The window transmitter module is also equipped with a temperature
measurement and EEPROM. The temperature measurement and
EEPROM components are connected to the measurement CPU through
the IIC-Bus interface. Individual calibration parameters are stored in the
EEPROM and are used to adapt individual settings, especially after
module exchange.
The basic principle of LTL212 is shown in Figure 21 below.
Transmitter
LED
Intensity
Measurement
Regulator
+Driver
Temperature
Measurement
EEPROM
CPU
Transmitter Clock
CPU
Derating
CPU
Transmitter Intensit
y
CPU
CPU
0401-034
Figure 21 Block Diagram LTL212
Measurement Head CPU LTC112
The measurement head CPU LTC112 (see Figure 22 below) is used for
the optics unit of the LT31 transmitter and as well for the LT31 receiver.
The hardware and software for transmitter and receiver are identical. The
CPU detects automatically if it is active in an LT31 transmitter or
receiver environment and selects the software configuration accordingly.
1104-094
Figure 22 Measurement Head CPU LTC112
The CPU section of the LTC112 is equipped with the following major
components: