Abaco Systems / VMIC VME-3122A-400000 High-Performance 16-Bit Analog-to-Digital Converter (ADC)

The Abaco Systems / VMIC VME-3122A-400000 is a 16-bit analog-to-digital converter module built on the VME form factor for high-speed data acquisition in embedded systems. The board delivers 64 differential or single-ended input channels with 16-bit resolution and a maximum throughput of 100 kHz, supporting program-selectable scanning of 1, 8, 16, 32, 48, or 64 channels. Dual-ported memory enables continuous scanning while the VMEbus remains available for real-time data access at 600 ns typical latency.

The module integrates software and external trigger modes, individually programmable channel gains (×1 or ×10), and selectable input voltage ranges spanning 0–5 V, 0–10 V, ±2.5 V, ±5 V, and ±10 V. A 500 Hz low-pass input filter option is available on the -400000 model variant. Common-mode rejection reaches a minimum of 75 dB across ±2.5 V and 0–5 V scales, with field-trim capability.

Direct interfacing with VMIC signal conditioning boards supports thermocouple, RTD, and strain gauge digitization, minimizing host processor overhead through on-board timers and programmable bus interrupt control.

Technical Specifications

• Resolution: 16-bit A/D conversion


• Input Channels: 64 differential or single-ended


• Voltage Ranges: 0–5 V, 0–10 V, ±2.5 V, ±5 V, ±10 V


• Maximum Throughput: 100 kHz


• Scanning Modes: 1, 8, 16, 32, 48, or 64 channels (program-selectable)


• Gain Control: Software-programmable per channel; fixed ×1 or ×10, or individually configured


• Common-Mode Rejection: Minimum 75 dB (±2.5 V and 0–5 V scales); field-trimmable


• Input Filter Option: 500 Hz (−3 dB) available on -400000 model


• Data Access Time: 600 ns typical (scanning), 1.2 µs maximum; 600 ns maximum (non-scanning)


• Memory: Dual-ported for concurrent scanning and VMEbus access


• Trigger Modes: Software and external trigger (P2 connector)


• Common-Mode Protection: 22 MΩ input pull-down resistor (option)

Key Features

• Minimizes host processor involvement through autonomous scanning and on-board timers


• Programmable bus interrupter for interrupt-driven data transfer


• Continuous digitization with stored results in dual-ported memory


• Individual channel gain configuration during active scanning


• Factory-selectable single-ended or differential input configuration


• Optional low-pass input filtering

Typical Applications

• High-speed multi-channel data acquisition in test and measurement systems


• Thermocouple, RTD, and strain gauge signal digitization


• Industrial control and monitoring platforms requiring VMEbus integration

Compatibility & Integration

• VMEbus architecture


• Direct interface with VMIC signal conditioning modules


• External trigger input on P2 connector