LTC2402IMS#PBF Linear Technology, LTC2402IMS#PBF Datasheet - Page 28

• Manufacturer Part Number: LTC2402IMS#PBF
• Description: IC ADC 24BIT 2CH MICROPWR 10MSOP
• Manufacturer: Linear Technology

Specifications of LTC2402IMS#PBF

• Number Of Bits: 24
• 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: 10-TFSOP, 10-MSOP (0.118", 3.00mm Width)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

LTC2401/LTC2402
APPLICATIO S I FOR ATIO
There are no extra control or status pins required to
perform the alternating 2-channel measurements. The
LTC2402 only requires two digital signals (SCK and SDO).
This simplification is ideal for isolated temperature mea-
surements or systems where minimal control signals are
available.
Pseudo Differential Applications
Generally, designers choose fully differential topologies
for several reasons. First, the interface to a 4- or 6-wire
bridge is simple (it is a differential output). Second, they
require good rejection of line frequency noise. Third, they
typically look at a small differential signal sitting on a
large common mode voltage; they need accurate
measurements of the differential signal independent of
28
SCK
SDO
U
EOC
U
CH1
Figure 32. Pseudo Differential Strain Guage Application
W
Figure 31. Embedded Selected Channel Indicator
CH1 DATA OUT
• • •
350
350
U
350
350
I
I
I
EXCITATION
DC
DC
= 0
= 0
2
3
4
5
FS
CH1
ZS
CH0
SET
SET
LTC2402
GND
V
5V
CC
1
the common mode input voltage. Many applications
currently using fully differential analog-to-digital con-
verters for any of the above reasons may migrate to a
pseudo differential conversion using the LTC2402.
Direct Connection to a Full Bridge
The LTC2402 interfaces directly to a 4- or 6-wire bridge, as
shown in Figure 32. The LTC2402 includes a FS
ZS
bridge. This eliminates errors due to excitation currents
flowing through parasitic resistors. The LTC2402 also
includes two single ended input channels which can tie
directly to the differential output of the bridge. The two
conversion results may be digitally subtracted yielding the
differential result.
SDO
SCK
CS
F
O
SET
EOC
9
8
7
10
for sensing the excitation voltage directly across the
3-WIRE
SPI INTERFACE
CH0
24012 F32
CH0 DATA OUT
• • •
24012 F31
SET
and a