VMIC VMIVME-3125 Analog Input Board

Module Feature

VMIVME-3125 is a single-slot 6U VMEbus analog input board developed by VMIC (GE Fanuc / Abaco Systems). It supports 32 single-ended or 16 differential analog input channels,equipped with one 12-bit ADC with track-and-hold circuit. Total hardware scan rate reaches 40 kHz;the module automatically scans all channels after power-up or reset without software initialization.Converted sampling data is stored in onboard dual-port memory for fast VME bus access. Input gain and voltage range are configurable via on-board jumpers,gain options ×1,×10,×100;input range covers ±50 mV ~ ±10 VDC,and it can support 4-20 mA current loop with auxiliary sub-board. 1000 VDC galvanic isolation separates analog ground and digital ground to suppress common-mode interference. Each channel integrates overvoltage protection and 50 kHz low-pass filter,optional 40 Hz low-pass filter daughter card for low-frequency noise reduction. VME bus interface supports A16/A24 addressing and D08/D16/D32 data transfer,works exclusively as VME slave. Built-in BIT diagnostic runs loopback self-test and monitors channel integrity,latches fault status for host reading. Rugged Eurocard PCB with conformal coating,shock and vibration screened for power plant cabinet environment,widely used in gas/steam turbine analog signal monitoring,hardware-in-loop real-time simulation,accelerator and aerospace ground test VME chassis.

Working principle

After power-on,hardware sequencer automatically cycles through all analog input channels. The track-and-hold circuit captures analog signal,12-bit ADC converts analog value to digital code,and sampling data is written to dual-port memory. VME host reads measurement data directly from dual-port memory without waiting for ADC conversion. BIT logic injects reference test voltage and reads conversion result to verify ADC and signal path health. VME FPGA completes address decoding and bidirectional data handshake between VME backplane and dual-port memory bank. Input protection circuit clamps surge voltage to prevent ADC damage.

Onboard components

VME interface FPGA,12 bit ADC with track & hold,analog multiplexer array,dual-port memory bank,programmable gain network,low-pass filter network,overvoltage protection circuit,BIT reference voltage source,VME J1/J2 edge connector,front-panel 64-pin analog I/O connector,multi-status LED array.

LED indicators

Front panel LED indicators for board +5 V power and module fault alarm.

Hardware self-diagnosis

Visual inspection of PCB,components and solder joints;board ID register readback verification;ADC full-scale and zero-point test;BIT reference loopback verification;VME A16/A24 read/write communication test.

Programming software

VMIC analog I/O driver library and configuration utility,supports VxWorks,Linux and QNX real-time operating systems;software tool for channel data reading and fault log retrieval.

Electrical & Process Parameters

Model: VMIVME-3125 Brand: VMIC Device type: 6U VMEbus multi-channel 12-bit analog input module Bus standard: VMEbus, A16/A24 addressing, D08/D16/D32 transfer Channel:32 single-ended /16 differential Resolution:12 bit Total scan rate:40 kHz Input range:±50 mV ~ ±10 VDC,jumper selectable gain ×1 / ×10 / ×100 Isolation:1000 VDC between analog and digital ground Control mode: VME slave access,auto hardware scan,dual-port memory,BIT built-in self-test,overvoltage protection Power supply: +5 V from VME backplane Cooling: Convection cooling Protection: Per-channel overvoltage protection,ESD protection,galvanic isolation Mounting: Standard single-height 6U VME front panel ejector locking Protection class: PCB with optional conformal coating

Mechanical & Structure

Mounting: Single-slot 6U VME Eurocard Protection class: PCB with optional conformal coating

Environmental

Operating temperature:0℃ ~ +55℃ Storage temperature:-40℃ ~ +85℃ Ambient humidity:20~80% non-condensing Certification: CE compliant Status: VMIC 6U VME isolated multi-channel analog input board

Installation

Follow ESD safety procedure before handling.Fully power off VME chassis.Insert VMIVME-3125 into vacant 6U VME slot and lock front panel ejector latches.Set jumpers for gain and input range according to field requirement.Connect analog sensors to front 64-pin I/O connector.Power on chassis,load VMIC analog I/O driver,run BIT loopback diagnostic before commissioning.

Interface

VME J1/J2 backplane connector,front-panel 64-pin analog I/O connector,fault status register pins.

Diagnostic

Board undetected: poor VME backplane contact,damaged edge connector or incorrect base address jumper setting. Channel reading drift: need gain and offset recalibration. Abnormal full-scale reading: overvoltage triggered protection or damaged analog front-end. BIT self-test fail: reference voltage circuit failure or ADC hardware fault.

Product Brief

VMIC VMIVME-3125 single height 6U VME analog input board,12-bit isolated ADC with auto hardware scan,32 single-ended/16 differential analog channels,dual-port memory for fast data acquisition,for turbine analog signal monitoring and hardware-in-loop simulation VME systems.