Measurement Computing USB-7204 - Manual (Page 21)

21
Chapter 4
Specifications
All specifications are subject to change without notice.
Typical for 25°C unless otherwise specified.
Specifications in italic text are guaranteed by design.
Analog input
Table 1. Analog input specifications
Parameter Conditions Specification
A/D converter type Successive approximation type
Input modes Single-ended or differential (default)
Input voltage range for linear
operation, single-ended mode CHx to GND ±10 volts (V) max
Input common-mode voltage range
for linear operation, differential
mode CHx to GND –10 V min, +20 V max
Absolute maximum input voltage CHx to GND ±28 V max
Input impedance 122
kΩ
Input current (Note 1) Vin = +10 V 70 microamperes (µA) typ
Vin = 0 V –12 µA typ
Vin = –10 V –94 µA typ
Number of channels 8 single-ended / 4 differential, software-selectable
Configuration Single A/D
Sampling method Multiplexed
Input ranges, single-ended mode ±10 V G=2
Input ranges, differential mode ±20 V G=1
±10 V G=2 (default)
±5 V G=4
±4 V G=5
±2.5 V G=8
±2.0 V G=10
±1.25 V G=16
±1.0 V
G=20
Software-selectable
Throughput (Note 2) Software paced 250 samples per second (S/s) typ, system dependent
Scan to system memory 0.596 to 50,000 S/s
Channel gain queue Up to 16 elements Software-selectable channel, range.
Resolution (Note 3) Differential 12 bits, no missing codes
Single-ended 11 bits
Integral linearity error ±1 least significant bit (LSB) typ
Differential linearity error ±0.5 LSB typ
Repeatability ±1 LSB typ
Trigger source Software-selectable External digital: TRIG_IN
Pacer source Software-selectable  Internal
 External (SYNC), rising edge triggered
 External Gated (SYNC), see Note 4
 Programmed IO
Calibration Factory Cal factors stored in firmware. Cal factors
must be applied via application software.