VMIC VMIVME-4900 Digital to Synchro / Resolver Converter Board

Module Feature

VMIVME-4900 is a single-slot 6U VMEbus digital-to-synchro/resolver converter board developed by VMIC (GE Fanuc), used to convert digital position angle data into analog synchro or resolver excitation signals, matched with high-power synchro booster amplifiers. It adopts 14-bit conversion architecture with angle accuracy of ±4 arc minutes. Dual independent output channels, channel 3-wire wiring for synchro and 4-wire wiring for resolver. AC output power options:1.5 VA,4.5 VA,5.0 VA. Built-in isolation transformers for galvanic separation between VME digital side and synchro analog side. Reference excitation frequency 400 Hz standard, reference voltage 26 Vrms. VME bus interface supports A16/A24 addressing and D08/D16/D32 data transfer, works as VME slave for angle register writing and fault status reading. BIT function supports real-time online monitoring and offline loopback self-test, detects power anomaly, reference loss and channel output fault, latches fault alarm and drives front panel LED indicator. Front panel AMP D-type connector provides direct field wiring for synchro/resolver actuators. Rugged Eurocard PCB with conformal coating,shock and vibration screened for power plant cabinet environment,widely used in gas/steam turbine angle position control,hardware-in-loop motion simulation,aerospace gimbal servo and legacy VME real-time control chassis.

Working principle

VME host writes digital angle value to board registers. 14-bit converter translates digital angle codes into three-phase synchro analog signals or two-phase resolver signals. Built-in isolation transformer isolates digital circuit and analog field circuit to suppress common-mode noise. BIT logic injects test angle value and samples analog output to verify conversion accuracy. VME FPGA completes address decoding and data handshake between host CPU and angle register bank. Overload protection circuit prevents damage to transformer and output amplifier under short-circuit field wiring.

Onboard components

VME interface FPGA,14-bit D/S converter core,dual-channel isolation transformer array,output power amplifier bank,reference 400 Hz oscillator,BIT fault detection circuit,VME J1/J2 edge connector,front-panel AMP D-type I/O connector,multi-status LED array.

LED indicators

Front panel LED indicators for board +5 V power,VME bus activity,BIT fault alarm and reference excitation status.

Hardware self-diagnosis

Visual inspection of PCB,front ejectors and solder joints;board ID register readback verification;BIT offline angle loopback test;reference oscillator health check;output overload protection verification;VME A16/A24 read/write communication test.

Programming software

VMIC VME device driver library,universal board configuration and BIT diagnostic utility,supports VxWorks,Linux and QNX real-time operating systems;software tool for angle value writing and fault log reading.

Electrical & Process Parameters

Model: VMIVME-4900 Brand: VMIC Device type: 6U VMEbus dual channel digital to synchro/resolver converter module Bus standard: VMEbus, A16/A24 addressing, D08/D16/D32 transfer Resolution:14 bit Angle accuracy: ±4 arcmin Channel: Dual channel Output mode:3 wire synchro /4 wire resolver Output power rating:1.5 VA,4.5 VA,5.0 VA Reference frequency:400 Hz Reference voltage:26 Vrms Control mode: VME slave access,built-in isolation transformer,online/offline BIT self-test,output overload protection Power supply: +5 V from VME backplane Cooling: Convection cooling Protection: Galvanic isolation,output short-circuit protection,overcurrent protection,ESD protection Mounting: Standard 6U VME front panel ejector locking Protection class: PCB with optional conformal coating

Mechanical & Structure

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

Environmental

Operating temperature: 0℃ ~ +60℃ Storage temperature: -40℃ ~ +85℃ Ambient humidity: 5~95% non-condensing Certification: CE compliant Status: VMIC 6U VME digital synchro/resolver output board

Installation

Follow ESD safety procedure before handling.Fully power off VME chassis.Insert VMIVME-4900 into vacant 6U VME slot and lock front panel ejector latches.Configure channel wiring mode (synchro / resolver) and power rating via hardware jumpers.Wire synchro/resolver actuators or booster amplifiers to front AMP D connector.Power on chassis,load VMIC VME driver,run BIT angle diagnostic before commissioning.

Interface

VME J1/J2 backplane connector,front-panel AMP D-type multi-pin synchro/resolver terminal header,fault status register pins.

Diagnostic

Board undetected: poor VME backplane contact,damaged edge connector or incorrect base address jumper setting. Angle output deviation: reference oscillator drift or transformer aging. Single channel no AC output: output amplifier fault or open field wiring. BIT persistent fault: missing reference excitation signal.

Product Brief

VMIC VMIVME-4900 single height 6U VME digital to synchro/resolver converter board,dual channel 14-bit angle conversion,built-in isolation transformer and BIT diagnostic,generates 400 Hz synchro/resolver analog signals for servo gimbal and turbine position simulation VME systems.