LTC2400CS8#PBF Linear Technology, LTC2400CS8#PBF Datasheet - Page 23

• Manufacturer Part Number: LTC2400CS8#PBF
• Description: IC A/D CONV 24BIT MICRPWR 8-SOIC
• Manufacturer: Linear Technology

Specifications of LTC2400CS8#PBF

• Number Of Bits: 24
• Sampling Rate (per Second): 7.5
• Data Interface: MICROWIRE™, Serial, SPI™
• Number Of Converters: 1
• Power Dissipation (max): 1mW
• Voltage Supply Source: Single Supply
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (0.154", 3.90mm Width)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

APPLICATIONS
Input Current (V
If complete settling occurs on the input, conversion re-
sults will be uneffected by the dynamic input current. If the
settling is incomplete, it does not degrade the linearity
performance of the device. It simply results in an offset/
full-scale shift, see Figure 16. To simplify the analysis of
input dynamic current, two separate cases are assumed:
large capacitance at V
tance at V
TUE
0
SOURCE
SIGNAL
INTPUT
IN
50
40
20
10
30
0
Figure 18. Offset vs R
(C
1
V
V
V
T
Figure 16. Offset/Full-Scale Shift
Figure 17. An RC Network at V
IN
CC
REF
IN
A
= 25 C
= 0V
IN
= 5V
< 0.01 F).
= 5V
R
)
10
C
SOURCE
C
C
U
IN
IN
IN
C
= 1000pF
= 0.01 F
IN
= 100pF
IN
= 0pF
100
R
(C
INFORMATION
SOURCE
U
V
IN
REF
V
C
IN
IN
> 0.01 F) and small capaci-
/2
( )
1k
SOURCE
C
PAR
W
20pF
10k
(Small C)
2400 F18
IN
100k
V
LTC2400
IN
2400 F17
2400 F16
U
V
REF
If the total capacitance at V
(< 0.01 F), relatively large external source resistances (up
to 20k for 20pF parasitic capacitance) can be tolerated
without any offset/full-scale error. Figures 18 and 19 show
a family of offset and full-scale error curves for various
small valued input capacitors (C
of input source resistance.
For large input capacitor values (C
spikes are averaged by the capacitor into a DC current. The
gain shift becomes a linear function of input source
resistance independent of input capacitance, see Figures
20 and 21. The equivalent input impedance is 1.66M .
This results in 1.5 A of input dynamic current at the
extreme values of V
Figure 19. Full-Scale Error vs R
–10
–30
–40
–50
300
250
200
150
100
–20
50
0
0
Figure 20. Offset vs R
1
0
V
V
V
T
V
V
V
T
CC
REF
IN
A
CC
REF
IN
A
100
= 25 C
= 25 C
= 0V
= 5V
= 5V
= 5V
= 5V
= 5V
200
C
10
C
IN
C
IN
IN
IN
C
= 1000pF
300
IN
= 100pF
= 0.01 F
= 0pF
(V
100
400
R
R
SOURCE
SOURCE
IN
500
= 0V and V
IN
600
( )
( )
1k
C
C
SOURCE
IN
IN
(see Figure 17) is small
IN
C
= 10 F
C
700
= 1 F
IN
IN
< 0.01 F) as a function
IN
SOURCE
= 0.1 F
= 0.01 F
800
10k
> 0.01 F), the input
(Large C)
900
2400 F19
2400 F20
IN
LTC2400
(Small C)
100k
1000
= V
REF
23
, when