Measurement Computing USB-2627 - Manual (Page 20)

20
Chapter 5
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. General analog input specifications
Parameter Condition Specification
A/D converter type Successive approximation
ADC resolution 16 bits
Number of channels 16 single-ended
Input voltage range ±10 V
Absolute maximum input
voltage CHx relative to AGND  ±25 V max (power on)
 ±10.5 V max (power off)
Input impedance  1 GΩ (power on)
 390 Ω (power off)
Input bias current ±100 pA
Input bandwidth Small signal (–3 dB) 3.1 MHz
Input capacitance 40 pf
Maximum working voltage ±10.1 V max relative to AGND
Crosstalk Adjacent channels, DC to
10 kHz –80 dB
Input coupling DC
Sampling rate 0.0149 Hz to 1,000 kHz; software-selectable
Trigger source TTLTRG
A/D pacing  Internal input scan clock
 External input scan clock (XAPCR)
Burst mode Burst rate = 1 µs, software selectable
Throughput Software paced 33 S/s to 4,000 S/s typ; system dependent
Hardware paced 1 MS/s max
Channel queue Up to 16 element list of random channels
Warm-up time 15 minutes min
Accuracy
Analog input DC voltage measurement accuracy
Table 2. DC Accuracy components and specifications. All values are (±)
Range Gain error
(% of reading) Offset error
(µV) INL error
(% of range) Absolute
accuracy at
Full Scale
(µV) Gain
temperature
coefficient
(% reading/°C) Offset
temperature
coefficient
(µV/°C)
±10 V 0.031 915 0.0076 4775 0.0013 35