LTC2400 Linear Technology, LTC2400 Datasheet - Page 35

• Manufacturer Part Number: LTC2400
• Description: 24-Bit uPower No Latency ADC in SO-8
• Manufacturer: Linear Technology

TYPICAL APPLICATIONS
A simpler, and potentially less expensive solution is the
use of the LT1025 as shown in Figure 37.
The LT1025 incorporates the functions of temperature
sensor, a precision divider chain required to produce the
appropriate correction for five different types of thermo-
couples, as well as curvature correction. The LT1025 must
be located at the cold junction. The use of a thermal mass
around the cold junction, as well as protection from air
currents, is advisable.
U
Figure 37. The LT1025 Complete Cold Junction Solution
GND
LT1025
4
V
5V
IN
2
R
Figure 38. Simplest Platinum RTD Interface
–
5
S
F
5V
6
R1*
12.1k
Pt RTD
100
*VISHAY S102 OR EQUIVALENT
S
–
TYPE
S
3
2
+
V
IN
V
REF
1
GND
V
5V
3
CC
LTC2400
4
60Hz
2
V
Simple Platinum RTD Interface
If high temperature resolution is required over a more
limited range, Figure 38 can resolve approximately
0.01 C without additional amplification. The resistance of
a platinum RTD changes by approximately 0.31 / C at
T
circuit does not compromise the stability, accuracy or
noise level of the LTC2400.
IN
0.1 F
V
A
REF
= 25 C. The 100 to 300 source impedance of this
F
O
1
GND
V
8
CC
LTC2400
SDO
SCK
4
60Hz
CS
50Hz
10k
0.1 F
5
6
7
F
O
8
2400 F37
SDO
SCK
5V
CS
50Hz
10k
5
6
7
2400 F36
5V
LTC2400
35