Input Sequencer; Frequency/Pulse Generators - Measurement Computing PCI-2511 User Manual

PCI-2511 User's Guide

Input sequencer

Analog, digital, and counter inputs can be scanned based on either an internal programmable timer or an
external clock source.
Parameter
Input scan clock sources
(Note 3)
Programmable parameters per scan
Depth
Onboard channel-to-channel scan rate
External input scan clock (XAPCR)
maximum rate
Clock signal range
Minimum pulse width
Note 3: The maximum scan clock rate is the inverse of the minimum scan period. The minimum scan period is equal to
1 µs times the number of analog channels.
If a scan contains only digital channels, then the minimum scan period is 250 ns. Some platforms can sustain
scan rates up to 83.33 ns for digital-only scans.

Frequency/pulse generators

Parameter
Channels
Output waveform
Output rate
High-level output voltage
Low-level output voltage
Table 5. Input sequencer specifications
Specification
Internal:
Analog channels from 1 µs to 1 sec in 20.83 nS steps

Digital channels and counters from 250 ns to 1 sec in 20.83 ns steps

External. TTL-level input (XAPCR):
Analog channels down to 1 µs min

Digital channels and counters down to 250 ns min

Programmable channels (random order)

Programmable gain

512 locations
Analog: 1 MHz max

Digital: 4 MHz if no analog channels are enabled, 1 MHz with analog

channels enabled
Analog: 1 MHz max

Digital: 4 MHz if no analog channels are enabled, 1 MHz with analog

channels enabled
Logical zero: 0 V to 0.8 V

Logical one: 2.4 V to 5.0 V

50 ns high, 50 ns low
Table 6. Frequency/pulse generator specifications
Specification
2 x 16-bit
Square wave
1 MHz base rate divided by 1 to 65535 (programmable)
2.0 V min @ –1.0 mA, 2.9 V min @ –400 µA
0.4 V max @ 400 µa
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Specifications