Datasheet

14
LT1021
TYPICAL APPLICATIONS
U
Ultralinear Platinum Temperature Sensor*
EQUIVALE T SCHE ATIC
U
W
LT1021-10
OUT
IN
GND
1021 TA10
–
+
R
S
†
100Ω AT
0°C
R4
4.75k
1%
R5
200k
1%
R6
619k
1%
7
4
6
2
3
LT1001
–15V
20V
R13
24.3k
R12
1k
R15
10k
R14
5k
R
F
**
654k
R11
6.65M
1%
R10
182k
1%
R2*
5k
R1**
253k
R3**
5k
R9
100k
R8
10M
–15V
V
OUT
=100mV/°C
–50°C ≤ T ≤ 150°C
R7
392k
1%
20V
STANDARD INDUSTRIAL 100Ω PLATINUM 4-WIRE SENSOR,
ROSEMOUNT 78S OR EQUIVALENT. α = 0.00385
TRIM R9 FOR V
OUT
= 0V AT 0°C
TRIM R12 FOR V
OUT
= 10V AT 100°C
TRIM R14 FOR V
OUT
= 5V AT 50°C
USE TRIM SEQUENCE AS SHOWN. TRIMS ARE NONINTERACTIVE
SO THAT ONLY ONE TRIM SEQUENCE IS NORMALLY REQUIRED.
FEEDBACK LINEARIZES OUTPUT TO ±0.005°C FROM
–50°C TO 150°C
WIREWOUND RESISTORS WITH LOW TC
†
*
**
D1
D2
D3
R1
R2
GND
LT1021 ES
Q1
Q2
D4
6.3V
OUTPUT
–
+
A1
INPUT
Q3