Measurement Computing PC-CARD DAS16, Руководство пользователя

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PC-CARD-DAS16/16AO User's Guide Specifications
Counter
Table 11. Counter specifications
Counter type 82C54
Configuration 3 down counters, 16 bits each
Source: Programmable external (Ctr 1 Clk) or 100 kHz internal source
Gate: Available at connector (Ctr 1 Gate), pulled to logic high via 10K
resistor (See Note 2)
Counter 1 - User counter
Output: Available at connector (Ctr 1 Out)
Source: Programmable, 1MHz or 10 MHz internal source
Gate:
Available at connector (A/D Pacer Gate), pulled to logic high
via 10K resistor.
Counter 2 - ADC Pacer Lower Divider
Output: Chained to Counter 3 Clock
Source: Counter 2 Output
Gate: Internal
Counter 3 - ADC Pacer Upper Divider
Output: Programmable as ADC Pacer clock. Available at user connector
(ADC Pacer out)
Clock input frequency 10 MHz max
High pulse width (clock input) 30 ns min
Low pulse width (clock input) 50 ns min
Gate width high 50 ns min
Gate width low 50 ns min
Input low voltage 0.8 V max
Input high voltage 2.0 V min
Output low voltage 0.4 V max
Output high voltage 3.0 V min
Crystal oscillator frequency 10 MHz
Frequency accuracy 50 ppm
Note 2:
If you are not driving the gate of User Counter 1, it is strongly recommended that it be connected to
+5V (VDD).
Power consumption
Table 12. Power consumption specifications
5V quiescent 150 mA typical, 170 mA max
Miscellaneous
Table 13. Miscellaneous specifications
Available at I\O connector (+5V Power)
Protected by resettable fuse:
Hold current:
350 mA max @ 20
°
C still air
Trip current: 700 mA min @ 20
°
C still air
Trip and recovery time: 100 mS max
+5 Volts
On resistance: 1.3 Ohms max
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