Measurement Computing Data Translation DT9857, Руководство пользователя

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Specifications
153
General-Purpose Counter/Timer Specifications
Table 27 lists the specifications for the general-purpose counter/timer (C/T 0) on the DT9857
and DT9857E modules.
Table 29: General Purpose Counter/Timer Specifications
Feature DT9857 and DT9857E Specifications
Number of general-purpose counter/timers 1
Internal reference clock 48 MHz
Resolution 32 bits per channel
Clock divider
Minimum:
Maximum: 2
4,294,967,296
Clock output
Minimum:
Maximum: 0.0112 Hz
24 MHz
Maximum clock or gate input frequency 24 MHz
a
a. The integrity of the signal degrades at frequencies greater than 10 MHz.
Minimum pulse width (minimum amount of time it takes a
C/T to recognize an input pulse) 50 ns
Input voltage range 0 to 3.3 V (+5 V tolerance)
Inputs
Input logic load:
High input voltage:
Low input voltage:
Low input current:
Input termination: 1 LVTTL
2.0 V minimum
0.8 V maximum
–0.2 mA maximum
22 k
Ω
Outputs
Output type:
High output:
Low output:
High output current:
Low output current:
Short circuit protected: LVTTL
2.4 V minimum
0.4 V maximum
–10 mA maximum
4 mA maximum
33 mA