Datasheet

LTC2433-1
25
24331fa
Figure 24. Offset Error vs Output Data Rate and Temperature
Figure 25. +FS Error vs Output Data Rate and Temperature
Figure 26. –FS Error vs Output Data Rate and Temperature
Figure 27. Noise Histogram (Output Rate = 100Hz,
V
CC
= 5V, V
REF
= 100mV, 125°C)
OUTPUT DATA RATE (READINGS/SEC)
0
OFFSET ERROR (LSB)
–8
0
60 70 80 90
24331 F24
10 20 30 40 50 100
8
V
CC
= 5V
V
REF
= 5V
V
INCM
= 2.5V
V
IN
= 0V
F
O
= EXT OSC
T
A
= 85°C
T
A
= 25°C
OUTPUT DATA RATE (READINGS/SEC)
–3
+FS ERROR (LSB)
3
9
15
0
6
12
20 40 60 80
24331 F25
10010030507090
T
A
= 85°C
V
CC
= 5V
V
REF
= 5V
IN
+
= 3.75V
IN
–
= 1.25V
F
O
= EXT OSC
T
A
= 25°C
OUTPUT DATA RATE (READINGS/SEC)
0
–FS ERROR (LSB)
0
3
6
40
24331 F26
–3
–6
–9
10
20
30
50 60 70 80 90 100
T
A
= 85°C
V
CC
= 5V
V
REF
= 5V
IN
+
= 1.25V
IN
–
= 3.75V
F
O
= EXT OSC
T
A
= 25°C
input and/or reference capacitors (C
IN
, C
REF
) are used, the
previous section provides formulae for evaluating the
effect of the source resistance upon the converter perfor-
mance for any value of f
EOSC
. If small external input and/
or reference capacitors (C
IN
, C
REF
) are used, the effect of
the external source resistance upon the LTC2433-1 typical
performance can be inferred from Figures 14, 15, 19 and
20 in which the horizontal axis is scaled by 139,800/f
EOSC
.
Third, an increase in the frequency of the external oscilla-
tor above 460800Hz (a more than 3× increase in the output
data rate) will start to decrease the effectiveness of the
internal autocalibration circuits. This will result in a pro-
gressive degradation in the converter accuracy and linear-
ity. Typical measured performance curves for output data
rates up to 100 readings per second are shown in Fig-
ures␣ 24, 25, 26, 27, 28 and 29. In order to obtain the
APPLICATIO S I FOR ATIO
WUUU
OUTPUT CODE
–1
NUMBER OF READINGS (%)
50
40
30
20
10
0
1
3
4
2433 F27
0
2
5
V
CC
= 5V
V
REF
= 0.1V
V
IN
= 0V
REF
+
= 0.1V
REF
–
= GND
IN
+
= GND
IN
–
= GND
F
O
= 2.048MHz
T
A
= 125°C
GAUSSIAN DISTRIBUTION
m = 3.1µV
σ = 1.59µV
RMS