DynamicSignals / Kinetic Systems V635-AA21 8-Channel, 100 kHz Frequency Counter

The DynamicSignals/Kinetic Systems V635-AA21 is an 8-channel frequency counter that measures input signals from 0.01 Hz to 100 kHz with high precision and minimal configuration overhead. This single-width, C-size VXIbus module delivers consistent performance across its frequency range and operates in both single-scan and continuous modes. The counter employs differential input circuits with integrated filtering and hysteresis to reject noise, while programmable switching thresholds and per-channel AC/DC coupling options adapt to diverse signal sources.

Technical Specifications

Channels: 8

Frequency Range: 0.01 Hz to 100 kHz

Input Voltage Range: 20 mV to 20 V peak-to-peak (differential inputs)

Input Coupling: Programmable AC or DC per channel

Observation Window: 1 ms to 1.024 s

Clock Rate Options: 1 MHz or 10 MHz (programmable)

Clock Accuracy: ±0.0001%

Time Base Accuracy: ±1 ppm (10°C to 50°C)

Counting Accuracy: ±0.01% (10 ms window, 1 MHz clock); ±0.001% (10 ms window, 10 MHz clock); improves with longer observation windows

Power Supply: 103.5–126.5 VAC or 207–253 VAC, 50–60 Hz

Key Features

Differential input circuitry with programmable switching threshold

Filtering and hysteresis for high noise immunity

TTL inputs available on D connector options

BNC input connectors supported

Static and dynamic configuration modes

Register-based VXIbus architecture

Data access via A32/A16 and D32/D16 transfers through Offset Register

Typical Applications

Shaft encoder monitoring for engine RPM measurement (automotive and jet aircraft)

Flow meter measurement

General-purpose pulse monitoring

Compatibility & Integration The V635-AA21 operates as a register-based VXIbus module compatible with standard VXIbus mainframes such as the V195-AA21. Configuration and data retrieval use standard VXIbus memory-mapped I/O addressing.