LTC2413IGN#TR Linear Technology, LTC2413IGN#TR Datasheet - Page 27

• Manufacturer Part Number: LTC2413IGN#TR
• Description: IC ADC 24BIT 50/60HZ MPWR 16SSOP
• Manufacturer: Linear Technology

Specifications of LTC2413IGN#TR

• Number Of Bits: 24
• Sampling Rate (per Second): 6.8
• Data Interface: MICROWIRE™, Serial, SPI™
• Number Of Converters: 2
• Power Dissipation (max): 1mW
• Voltage Supply Source: Single Supply
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 16-SSOP (0.150", 3.90mm Width)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

APPLICATIO S I FOR ATIO
Figure 22. Offset Error vs Common Mode Voltage
(V
( R
INCM
IN
Figure 20. +FS Error vs R
Figure 21. –FS Error vs R
= R
= IN
SOURCEIN
+
= IN
–120
–180
–240
–300
–100
–120
–60
–20
–40
–60
–80
300
240
180
120
120
100
80
60
40
20
60
0
0
0
–
0 100 200 300 400 500 600 700 800 900 1000
0 100 200 300 400 500 600 700 800 900 1000
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5
) and Input Source Resistance Imbalance
+ – R
A: R
B: R
C: R
D: R
V
REF
REF
IN
IN
F
T
V
REF
REF
IN
IN
F
T
O
A
O
A
CC
CC
+
–
+
–
U
= GND
= 25 C
= GND
= 25 C
IN
IN
IN
IN
A
B
C
D
E
F
G
+
= 3.75V
= 1.25V
+
–
= 1.25V
= 3.75V
SOURCEIN
–
= 5V
= 5V
= 5V
= 5V
= GND
= GND
= +400
= +200
= +100
= 0
V
REF
REF
IN
SOURCE
U
SOURCE
F
T
R
C
CC
R
R
+
O
A
IN
SOURCEIN
SOURCE
SOURCE
+
–
= IN
V
–) for Large C
= 5V
= GND
= 25 C
= 10 F
INCM
= 5V
= GND
–
C
C
C
= V
(V)
IN
IN
IN
at IN
at IN
( )
( )
– = 500
= 1 F, 10 F
INCM
= 0.01 F
= 1 F, 10 F
C
E: R
F: R
G: R
C
C
IN
W
IN
IN
+
+
= 0.01 F
= 0.1 F
= 0.1 F
or IN
or IN
IN
IN
IN
= –100
= –200
IN
= –400
Values (C
–
–
2413 F19
2413 F21
2413 F22
(Large C
(Large C
U
IN
IN
IN
)
)
1 F)
Reference Current
In a similar fashion, the LTC2413 samples the differential
reference pins REF
charge to and from the external driving circuits, thus
produces a dynamic reference current. This current does
not change the converter offset but it may degrade the gain
and INL performance. The effect of this current can be
analyzed in the same two distinct situations.
For relatively small values of the external reference capaci-
tors (C
settles almost completely and relatively large values for
the source impedance result in only small errors. Such
values for C
gain performance without significant benefits of reference
filtering and the user is advised to avoid them.
Larger values of reference capacitors (C
be required as reference filters in certain configurations.
Such capacitors will average the reference sampling charge
and the external source resistance will see a quasi con-
stant reference differential impedance. When internal os-
cillator is used (F
resistance is 1.43M which will generate a gain error of
approximately 0.35ppm for each ohm of source resis-
tance driving REF
external oscillator with a frequency f
sion clock operation), the typical differential reference
resistance is 0.20 • 10
resistance drving REF
2.47 • 10
resistance on the two reference pins is additive with
respect to this gain error. The typical +FS and –FS errors
for various combinations of source resistance seen by the
REF
nected to these pins are shown in Figures 23, 24, 25
and 26.
In addition to this gain error, the converter INL perfor-
mance is degraded by the reference source impedance.
When internal oscillator is used(F
source impedance driving REF
about 1.2ppm additional INL error. When F
an external oscillator with a frequency f
of source resistance driving REF
about 8.73 • 10
+
and REF
REF
–6
< 0.01 F), the voltage on the sampling capacitor
• f
REF
EOSC
–
pins and external capacitance C
will deteriorate the converter offset and
O
ppm gain error. The effect of the source
–6
+
+
= LOW), the typical differential input
and REF
or REF
• f
12
EOSC
/f
EOSC
+
–
–
. When F
ppm additional INL error.
transfering small amount of
or REF
+
+
O
and each ohm of source
or REF
or REF
= LOW), every 100 of
EOSC
–
O
REF
EOSC
LTC2413
(external conver-
–
is driven by an
will result in
–
translates into
translates into
> 0.01 F) may
O
, every 100
is driven by
sn2413 2413fs
REF
27
con-