LTC2420IS8 Linear Technology, LTC2420IS8 Datasheet - Page 27

• Manufacturer Part Number: LTC2420IS8
• Description: IC ADC 20BIT MICROPOWER 8SOIC
• Manufacturer: Linear Technology

Specifications of LTC2420IS8

• Number Of Bits: 20
• Sampling Rate (per Second): 7.5
• 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: 8-SOIC (0.154", 3.90mm Width)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

APPLICATIO S I FOR ATIO
After acquiring 100 samples/second data the F
be driven LOW enabling 60Hz rejection to 110dB and the
highest possible DC accuracy. The no latency architecture
of the LTC2420 allows consecutive readings (one at 100
samples/second the next at 7.5 samples/second) without
interaction between the two readings.
–10
–20
–25
–30
–40
–15
–35
–5
10
5
0
Figure 31. Total Unadjusted Error at
100 Samples/Second (No Averaging)
0
U
INPUT VOLTAGE (V)
U
V
V
W
CC
REF
Figure 30. Total Error vs V
= 5V
= 2.5V
2420 F31
256
224
192
160
128
96
64
32
2.5
0
1.0
OUTPUT RATE = 100sps
1.5
O
U
pin may
2.0
REFERENCE VOLTAGE (V)
2.5
3.0
REF
As shown in Figure 33, the LTC2420 can capture transient
data with 90dB of dynamic range (with a 300mV
signal at 2Hz). The exceptional DC performance of the
LTC2420 enables signals to be digitized independent of a
large DC offset. Figures 34a and 34b show the dynamic
performance with a 15Hz signal superimposed on a 2V DC
level. The same signal with no DC level is shown in Figures
34c and 34d.
3.5
(Output Rate = 100sps)
4.0
12 BITS
13 BITS
14 BITS
15 BITS
4.5
2420 F30
–10
–2
–4
–6
–8
5.0
6
4
2
0
Figure 32. Total Unadjusted Error at
7.5 Samples/Second (No Averaging)
0
INPUT VOLTAGE (V)
V
V
CC
REF
= 5V
2420 F32
= 5V
LTC2420
5
P-P
27
input