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PCI-20007M-1A Counter/Timer I/O Module Overview

16-Bit, 4 Channel Counter/Timer Expansion I/O Module

The PCI-20007M-1A option module performs a number of important time domain operations and is useful in many precision applications. It adds pulse-counting and pulse-generation, timebase-generation, event-counting, accumulation, frequency-measurement, and quadrature- decoding capabilities to any expandable Intelligent Instrumentation board.

In addition, the rate generator output can be linked to any other option module through the I3 Bus to perform sync or other functions. In addition to a rate generator, the PCI-20007M-1A has four independent 16-bit counter/timer blocks and two quadrature decoders. As a result, it supports several simultaneous tasks, including multiple input and pulse-generation functions. You can also cascade two pairs of counters to form two 32-bit counters.

All direct input and output signals are TTL compatible. If you encounter other levels (as with AC line voltage switching or remote I/O situations where ground loop connections must be broken), you may be able to use the PCI-1100 Series opto-isolators to provide logic-level conversion.

Features & Benefits

•Four Counters

•16/32-Bit Operation (1 Part in 65K)

•8MHz Clock Rate

•0.01% Stability Timebase Dual Channel

Hardware Specifications

Parameter	Conditions	Specifications

Counters*
Number		4
Clock Speed		8MHz maximum
Input Levels		TTL compatible
Input Current, High-level	200µA
Input Current, Low-level	200µA
Output Levels		TTL compatible
Source Current	Vout = high	2mA
Sink Current	Vout = low	400mA
Timebase Generator*
Type Crystal-based Rate/burst generator	Resolution	125nS
Output Frequency Range		0.002Hz to 2MHz
Quadrature Decoders
Number		2 pairs of TTL inputs (Schmitt Trigger)
System Throughput**
Counter Readings		70,000 readings/second
Physical Characteristics
Power Requirements***		+5V 240mA maximum
Operating Temperature Range		0 to 70° C
* When the system is first powered up, the outputs of this option module are NOT in a determined state until initialized by software. Therefore the outputs could be "high" or "low".
** Hardware limit only. Software may reduce speed.
*** Refer to the data sheet of the host board to determine available power.