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21
Chapter 4
Specifications
All specifications are subject to change without notice.
Typical for 25 °C unless otherwise specified.
All specifications apply to all temperature and voltage input channels unless otherwise specified.
Specifications in
italic
text are guaranteed by design.
Analog input
Table 1. General analog input specifications
Parameter
Conditions
Specification
A/D converter type
ADS1256, 24-bit Sigma Delta
A/D data rates
3750 S/s, 2000 S/s, 1000 S/s, 500 S/s, 100 S/s, 60 S/s, 50 S/s,
25 S/s, 10 S/s, 5 S/s, 2.5 S/s
Throughput
Single channel: 2.5 S/s to 1102.94 S/s (software-selectable)
Multiple channels: 0.16 S/s to 551.47 S/s (software-
selectable)
See Table 11 and Table 12 for details.
Number of channels
16 single-ended or 8 differential (software-selectable).
Thermocouples require differential mode. For each channel
configured as differential, you essentially lose two single-ended
channels.
Input isolation
500 VDC min between field wiring and USB interface
Channel configurations
Temperature sensor input, software-selectable to match sensor
type
Voltage input
Input voltage range
Thermocouple mode
±0.078125 V
Voltage mode (Note 1)
±10 V, ±5 V, ±2.5 V, ±1.25 V, ±0.625 V, ±0.3125 V,
±0.15625 V, ±0.078125 V (software-selectable)
Absolute maximum input
voltage
CxH-CxL relative to
GND
±22 V max (power on)
±10 V max (power off)
Input impedance
10 MΩ (power on)
390 Ω (power off)
Input leakage current
±20 nA
Input voltage >±30 V
(power on/off)
±1 µA max
Input capacitance
590 pf
Maximum working voltage
( common mode)
Voltage mode
±10.25 V max
Common mode rejection
ratio (Note 1)
Thermocouple mode,
(f
IN
= 60 Hz)
110 dB
Voltage mode,
(f
IN
= 60 Hz, all input
ranges)
90 dB
ADC resolution
24 bits
Crosstalk
Adj chan, DIFF mode
100 dB
Input coupling
DC
Channel gain queue
Up to 64 elements
Software-selectable channel and range
Warm-up time
45 minutes min
Open thermocouple detect
Software-selectable for each channel.