GE VMIVME-4514A 16 channel scanning analog I/O board

GE VMIVME-4514A 16 channel scanning analog I/O board

Product Overview

VMIVME-4514A is a 16 channel scanning analog I/O board with built-in testing capabilities and P2 I/O connections. It provides 16 analog output channels and 16 analog input channels, with both input and output resolutions of 12 bits. Each channel of the analog output is designed with a sample and hold (S&H) output, and 16 analog inputs are digitized by a 12 bit analog-to-digital converter (ADC) controlled by a scanner, which can store data in dual port memory.

Core functions and features

Main functions

Continuously digitize all input channels and store the results in dedicated channel dual port registers (automatic scanning mode).

It has three A/D operation modes: automatic scanning mode when powered on, random polarization mode, and scanning polarization mode.

Supports P2 I/O connection, built-in onboard testing function, capable of testing 100% of active components.

Using semiconductor output switches does not affect accuracy (output impedance 0.1 Ω).

Analog input characteristics

16 single ended/differential (SE/Diff) analog input channels, 12 bit A/D converter.

Supports unipolar (0 to+10 V, 0 to+5 V) or bipolar (± 2.5 V, ± 5 V, ± 10 V) inputs.

A/D throughput of 40 kHz, optional low-pass filter, with overvoltage protection function.

Input relevant parameters: A/D conversion time of 15 µ s, acquisition time of 10 µ s, common mode range of ± 11 V (maximum), common mode rejection ratio of 82 dB, maximum input bias current of 2 nA, overvoltage protection of ± 40 V (maximum), data transmission type of D16.

Accuracy: 0.04% range ± 2 mV, can be calibrated to 0.02% ± 0.5 mV.

Analog output characteristics

16 sample and hold (S&H) analog output channels, 12 bit D/A converter.

The output has short-circuit protection and supports unipolar (0 to+10 V, 0 to 5 V) or bipolar (± 2.5 V, ± 5 V, ± 10 V) output.

The program can choose a scanning rate to provide better response for complex output functions, with an output current of 10 mA.

Output related parameters: resolution of 12 bits (per channel S&H), output impedance of 0.1 Ω, total error of 0.05% of full-scale range, and maximum setup time of 1.7 ms to reach 1 LSB.

Refresh update rate: default 550 Hz, fast refresh 1600 Hz (note: output refresh temporarily stops during input analog-to-digital conversion, so the output refresh rate decreases with the increase of analog-to-digital conversion rate. In the worst case scenario of automatic scanning mode, the default refresh rate is 300 Hz, and fast refresh is 900 Hz).

Operation Mode

Automatic scanning mode: Through power on system reset or program selection execution, all channels are continuously scanned, and digital data is stored in 16 16 bit dual port registers. It only needs to be read from the dual port registers without further programming.

Random polling mode: It is necessary to control the program to generate a single transition, and determine whether the transition is completed through the polling transition end status bit.

Scanning polarization mode: Perform a single scan of all channels, and determine whether the scan is complete through the polarization scan end control bit.

Other Features

Board address and VMEbus access

The physical address of the board can be selected through jumper wires on the board, and decoding the VMEbus address lines A06 to A15 is used for board selection.

The address modification bit is selected and decoded through jumper wires, supporting non privileged short I/O, monitoring short I/O, or both. The factory is configured to monitor short I/O.

Data transmission and format

Output data transmission: The data of each analog output channel is directly written to the RAM location dedicated to a specific channel on the board, and then periodically retrieved from the RAM and converted into analog voltage, which is transmitted to one of the 16 output sample and hold buffers.

Analog input format: The analog input is first digitized, and then the 12 bit digital value (D11 to D00) is read from a single storage word position in the channel specific dual port register. In binary complement mode, the high four bits (D15, D14, D13, D12) are read as sign extensions of the 12 bit digital value, otherwise they are read as logical zeros.

Testing and Resetting

Simulated I/O testing mode: Built in testing logic supports testing all active components (including output switches) on the board, supports real-time and offline testing, and utilizes the ADC multiplexer on the board.

Memory testing: Designed with onboard dual port memory, additional operational verification can be performed by performing memory diagnostics.

System reset: Initialize the board to a state where all analog outputs and output connectors (P2) are disconnected through the VMEbus application system reset signal.

Front panel malfunction LED

If an error occurs during the diagnostic process, the software controlled LED will light up to visually indicate the fault. The LED will be reset and lit by the system during power up, and will turn off after successful diagnosis.

Bus interface and physical environment characteristics