Datasheet

10
LT1236
TYPICAL APPLICATIONS
U
LT1236-10
OUT
IN
GND

LT1236 TA16
15V
8.87k
1%
1.24k
1%
10k
1%
D1
1N457
50k 
TC TRIM*
10k
1%
D2
1N457
50k
200k
1%
50k
ROOM TEMP
TRIM
10.36k
1%
8.45k
1mA
TRIMS 1mA REFERENCE CURRENT 
TC BY ±40ppm/°C. THIS TRIM 
SCHEME HAS VERY LITTLE EFFECT ON ROOM
TEMPERATURE CURRENT TO MINIMIZE ITERATIVE
TRIMMING
*
DAC
Precision DAC Reference with System TC Trim
2-Pole Lowpass Filtered Reference
Strain Gauge Conditioner for 350Ω Bridge
LT1236-10
OUT
IN
GND

LT1236 TA08
–
+
–
+
LM301A
†
100pF
8
1
6 6
3
2
–5V
357Ω
1/2W
–15V
R5
2M
R6*
2M
LT1012C
2
3
R4
20k
R2
20k
5V
R3
2M
V
OUT
X100
350Ω STRAIN
GAUGE BRIDGE**
28mA
28.5mA
R1
357Ω
1/2W
15V
THIS RESISTOR PROVIDES POSITIVE FEEDBACK TO 
THE BRIDGE TO ELIMINATE LOADING EFFECT OF 
THE AMPLIFIER. EFFECTIVE Z
IN
OF AMPLIFIER 
STAGE IS ≥ 1MΩ. IF R2 TO R5 ARE CHANGED,
SET R6 = R3
*
BRIDGE IS ULTRA-LINEAR WHEN ALL LEGS ARE
ACTIVE, TWO IN COMPRESSION AND TWO IN TENSION,
OR WHEN ONE SIDE IS ACTIVE WITH ONE COMPRESSED
AND ONE TENSIONED LEG
OFFSET AND DRIFT OF LM301A ARE VIRTUALLY
ELIMINATED BY DIFFERENTIAL CONNECTION OF LT1012C
**



†
LT1236-10
OUT
GND

LT1236 TA13
2.5mA
–10V (I
LOAD
≤ 1mA)
–11V TO –40V
27Ω
LM334
Negative Shunt Reference Driven
by Current Source
LT1236
OUT
IN
GND

LT1236 TA12
–
+
R1
36k
1µF
MYLAR

0.5µF
MYLAR

R2
36k
LT1001
V
IN
V
IN
V
REF
–V
REF
f = 10Hz
TOTAL NOISE 
≤2µV
RMS

1Hz ≤ f ≤ 10kHz