Acromag / Xembedded / Xycom AcPC482 Counter / Timer Module with Quadrature

The Acromag AcPC482 is a CompactPCI counter/timer module delivering ten 16-bit multifunction counters with quadrature input capability for precision position measurement and timing control. Engineered for industrial automation, motion control, and data acquisition systems, the module combines event counting, frequency measurement, pulse width modulation, and watchdog timer functionality in a single compact form factor. The 20 MHz internal clock time base ensures nanosecond-level timing accuracy across all measurement and generation modes.

Technical Specifications

Counter/Timer Architecture

• Ten 16-bit multifunction counter/timers


• Two 16-bit counters combinable into one 32-bit counter


• Quadrature position measurement with external clock support up to 8 MHz


• Internal programmable clocks: 1.25, 2.5, 5, 10, or 20 MHz


• Maximum output pulse/square wave frequency: 200 nS (20 MHz clock)


• Minimum event pulse width: 100 nS


• Minimum pulse width measurement: 100 nS


• Minimum period measurement: 200 nS Counter/Timer Modes

Pulse width modulation (PWM), watchdog timer, event counting, frequency measurement, pulse width measurement, period measurement, one-shot pulse output, repetitive pulse output, time/period interrupt, and square wave/pulse train generation. Digital I/O

• 16 bi-directional digital I/O channels (12 channels on PMC482R/PMC482RE models)


• Programmable per-channel input or output configuration


• Interrupt-on-change capability: state change, low-level, or high-level transitions


• TTL I/O on 482 models; mixed TTL/RS422 on 483 models; RS422 only on 484 models


• TTL specifications: VIH = 2.0 V, VIL = 0.8 V


• Buffered inputs with 4.7 kΩ pull-ups to +5 V Accuracy & Timing


• Waveform generation period: ±125 nS (±62 nS for IP482 at 32 MHz carrier)


• Watchdog timeout: ±1 clock cycle


• Pulse/period measurement: ±1 clock cycle

Key Features

• PCI Local Bus Specification Revision 2.2 compliance


• 5 V and 3.3 V signaling support


• Front panel SCSI-3 connector for field I/O


• 64-pin rear I/O connector (PMC482R/PMC482RE)


• 32, 16, or 8-bit register access through PCI memory space


• Operating temperature: 0 to 70°C (extended -40 to 85°C available on 'E' models)

Typical Applications Industrial automation, motion control systems, encoder interface, event logging, precision timing, pulse generation, and frequency measurement in embedded control environments.