VME-64SD1

This VME-64SD1 high density intelligent DSP-based card incorporates up to sixteen (16) single-speed or eight (8) two-speed transformer isolated Synchro/Resolver-to-Digital tracking converters with extensive diagnostics, digital velocity outputs, angle change alert, and optional programmable reference supply. Any combination of two-speed and single-speed channels can be field programmed to any ratio between 2 and 255. Each channel also produces differential (A & B) incremental encoder outputs (with programmable resolution) and a zero degree marker pulse. Alternatively, commutation outputs are available for 4, 6, or 8 pole brushless DC motors that eliminate the need for Hall Effect sensors on the motor, thus eliminating processor time and reducing bus traffic. For 2-speed usage, ambiguity circuits maintain monotonic outputs by compensating for misalignment between the Coarse and Fine Synchros. However, the processor will set a flag when VME-64SD1 senses that the maximum allowable misalignment of 90°/gear ratio is exceeded. This card, even when large accelerations are encountered, never looses tracking, because it incorporates the unique capability to automatically shift to higher bandwidths. The shifting is smooth and continuous with no glitches. Tracking rates are only limited to bandwidth restrictions, up to 150 RPS, at 16-bit resolution. The LATCH feature permits the user to read all channels at the same time. Reading will unlatch that channel. The angle alert monitors each channel for the programmed angle difference and sets an interrupt as soon as that threshold is reached. Thus, no polling of the angle registers is required until an angle has reached the specified difference. The use of Type II servo loop processing techniques enables tracking, at full accuracy, up to the specified rate. A step input will not cause any hang-up condition. Intermediate transparent latches, on all angle and velocity outputs, assure that valid data is always available without interrupts or waiting time. Our synthetic reference compensates for ±60° phase shifts, thus eliminating the need for individual compensation networks. Each channel can be specified for a different voltage or frequency. A watchdog timer is provided to monitor the processor. Part number, S/N, Date Code and Revision are stored in permanent memory. This board can operate over a "C" or "M" operating temperature range (see part number).

The VME-64SD1 "C" version (0°C to +70°C) uses standard high quality commercial semiconductors. The "M" version (-55°C to +85°C), used for severe environmental conditions, uses high quality extended temperature semiconductors. Conduction cooling, using a thermal plane and wedge locks, can be specified in the part number.