Linear Technology LTC2418CGN, 8-Channel Differential Input 24-Bit ADC, (req DC590) DC571A DC571A Data Sheet
Product codes
DC571A
LTC2414/LTC2418
1
241418fa
APPLICATIO S
U
FEATURES
DESCRIPTIO
U
TYPICAL APPLICATIO
U
The LTC
®
2414/LTC2418 are 8-/16-channel (4-/8-differ-
ential) micropower 24-bit
∆Σ analog-to-digital convert-
ers. They operate from 2.7V to 5.5V and include an
integrated oscillator, 2ppm INL and 0.2ppm RMS noise.
They use delta-sigma technology and provide single cycle
settling time for multiplexed applications. Through a
single pin, the LTC2414/LTC2418 can be configured for
better than 110dB differential mode rejection at 50Hz or
60Hz
integrated oscillator, 2ppm INL and 0.2ppm RMS noise.
They use delta-sigma technology and provide single cycle
settling time for multiplexed applications. Through a
single pin, the LTC2414/LTC2418 can be configured for
better than 110dB differential mode rejection at 50Hz or
60Hz
±2%, or they can be driven by an external oscillator
for a user-defined rejection frequency. The internal oscil-
lator requires no external frequency setting components.
lator requires no external frequency setting components.
The LTC2414/LTC2418 accept any external differential
reference voltage from 0.1V to V
reference voltage from 0.1V to V
CC
for flexible ratiometric
and remote sensing measurement applications. They can
be configured to take 4/8 differential channels or
8/16 single-ended channels. The full-scale bipolar input
range is from – 0.5V
be configured to take 4/8 differential channels or
8/16 single-ended channels. The full-scale bipolar input
range is from – 0.5V
REF
to 0.5V
REF
. The reference common
mode voltage, V
REFCM
, and the input common mode volt-
age, V
INCM
, may be independently set within GND to V
CC
.
The DC common mode input rejection is better than 140dB.
The LTC2414/LTC2418 communicate through a flexible
4-wire digital interface that is compatible with SPI and
MICROWIRE
4-wire digital interface that is compatible with SPI and
MICROWIRE
TM
protocols.
■
Direct Sensor Digitizer
■
Weight Scales
■
Direct Temperature Measurement
■
Gas Analyzers
■
Strain Gauge Transducers
■
Instrumentation
■
Data Acquisition
■
Industrial Process Control
, LTC and LT are registered trademarks of Linear Technology Corporation.
■
8-/16-Channel Single-Ended or 4-/8-Channel
Differential Inputs (LTC2414/LTC2418)
Differential Inputs (LTC2414/LTC2418)
■
Low Supply Current (200
µA, 4µA in Autosleep)
■
Differential Input and Differential Reference
with GND to V
with GND to V
CC
Common Mode Range
■
2ppm INL, No Missing Codes
■
2.5ppm Full-Scale Error and 0.5ppm Offset
■
0.2ppm Noise
■
No Latency: Digital Filter Settles in a Single Cycle
Each Conversion Is Accurate, Even After a New
Channel is Selected
Each Conversion Is Accurate, Even After a New
Channel is Selected
■
Single Supply 2.7V to 5.5V Operation
■
Internal Oscillator—No External Components
Required
Required
■
110dB Min, 50Hz/60Hz Notch Filter
8-/16-Channel
24-Bit No Latency
∆Σ
TM
ADCs
No Latency
∆Σ is a trademark of Linear Technology Corporation. All other trademarks are the
property of their respective owners.
Total Unadjusted Error
vs Input Voltage
SDI
SCK
SDO
CS
F
O
REF
+
V
CC
9
11
2.7V TO 5.5V
20
18
17
16
19
1
µF
COM
REF
–
GND
10
THERMOCOUPLE
12
15
DIFFERENTIAL
24-BIT
∆Σ ADC
16-CHANNEL
MUX
+
–
241418 TA01a
4-WIRE
SPI INTERFACE
SPI INTERFACE
LTC2418
= 50Hz REJECTION
= EXTERNAL OSCILLATOR
= 60Hz REJECTION
= EXTERNAL OSCILLATOR
= 60Hz REJECTION
V
CC
CH0
CH1
CH1
•
•
•
•
•
•
21
22
22
CH7
CH8
CH8
28
1
CH15
8
INPUT VOLTAGE (V)
–2.5 –2
–1
0
1.0
2.0
TUE (ppm OF V
REF
)
3
2
1
0
–1
–2
–3
–1.5
–0.5
0.5
1.5
2414/18 TA01b
2.5
V
CC
= 5V
V
REF
= 5V
V
INCM
= V
REFCM
= 2.5V
F
O
= GND
T
A
= 85
°C
T
A
= 25
°C
T
A
= –45
°C