VMIC VMIVME-1128 128-Bit High Voltage Digital Input Board

The VMIC VMIVME-1128 is a high-density digital input board designed for VMEbus systems, providing 128 channels of high-voltage digital input capability. This module is engineered for industrial data acquisition applications requiring reliable monitoring of field contact states, limit switches, and discrete sensor signals.

VMEbus Compliance

The VMIVME-1128 complies with the VMEbus Specification Rev. C.1, supporting A24 and A16 addressing modes with D32, D16, and D08 data transfers. The addressing scheme implements thirty-two bytes individually addressable, with a Board ID Register located at the base address, a Control and Status Register stacked above, and sixteen input bytes accessible above the CSR. Twenty jumpers establish the base address configuration, while an additional jumper selects standard or short I/O accesses.

Built-in-Test Capabilities

This board incorporates comprehensive built-in-test logic that supports board-level diagnostics exercising all on-board active components. Special output registers are provided to test input circuitry, controlled by a test mode bit in the Control and Status Register. A front panel Fail LED illuminates at power-up and can be extinguished under program control upon successful completion of user-defined diagnostic software, enabling rapid fault detection and isolation.

Input Threshold Characteristics

The VMIVME-1128 accepts input voltages ranging from 0 to 66 V with user-selectable threshold levels from 0.61 to 34 V. Inputs feature high impedance (15 kΩ) with threshold accuracy of 10 percent for inputs from 3 to 66 V and ±200 mV for inputs from 0 to 3 V. This wide operating range accommodates various industrial sensor types including 5V TTL, 12V, 24V, and 48V logic levels.

• Input Channels: 128 bits organized as 16 ports

• Input Voltage Range: 0 to 66 VDC

• Threshold Range: 0.61 V to 34 V (jumper-selectable)

• Input Impedance: 15 kΩ typical

• Addressing: A24:A16:D32/D16/D08 (EO)

• Form Factor: 6U Double Eurocard

• Connector Type: Two 96-pin DIN connectors

• Power Requirement: +5 VDC ±5 percent, 2.31 A typical

• Operating Temperature: 0°C to +55°C

Physical Specifications

The VMIVME-1128 measures 9.2 inches in height and 6.3 inches in depth, conforming to the 6U Double Eurocard form factor. It utilizes high-reliability DIN-type I/O connectors compatible with mass-terminated ribbon cables or discrete wire terminations. The board operates within a relative humidity range of 20 to 80 percent non-condensing and is designed for forced air convection cooling within VME chassis environments.