VME Time & Frequency Processor
P/N 001000157
KEY FEATURES
- 6U, Single Width VME
- Time Code Inputs
- Time Code Output
- 1PPS Pulse Rate Output/Interrupt
- Frequency Outputs (1, 5, 10 MHz)
- External Event Capture/Interrupt
- Programmable Periodic Output/Interrupt
- Programmable Time Strobe Output/Interrupt
Brandywine Communications’ VME635091-SYNCCLOCK is a time and frequency processor module that provides precision time and frequency reference to the host computer and peripheral data acquisition systems. Time is acquired from time code signals, typically IRIG B. Time is displayed on the front panel (hours, minutes, seconds) via LED digits.
Central to the operation of the module is a disciplined 10 MHz oscillator and 100-nanosecond clock. Current time (days to 100 nanoseconds) can be accessed across the bus with zero latency, which allows for very high-speed time requests. The oscillator is rate matched (disciplined) to the input time source and drives the precision 10 MHz frequency output and time code generator circuitry. If the time source is lost, the module will continue to maintain time (flywheel).
Both time code generation and translation are supported. The generator supplies IRIG B time code output that is synchronized to the input time source. The translator decodes IRIG B time code inputs.
An event time capture feature provides a means of latching the time of an event input and/or generating a bus interrupt that is coincident with an external TTL pulse. The module can also be programmed to generate a periodic pulse rate/interrupt as well as to generate a strobe/interrupt at a single predetermined time.
| Real time clock | |
| Bus request resolution: | 100 nanoseconds |
| Bus request latency: | Zero |
| Major time format: | Binary or BCD |
| Minor time format: | Binary |
| Time code translator | |
| Time code formats: | IRIG A, IRIG B (modulated or DCLS) |
| Modulation ratio: | 3:1 to 6:1 |
| Input amplitude: | 500 mV to 5 V P-P |
| Input impedance: | >10KΩ (AC coupled) |
| Time code generator | |
| Time code format: | IRIG B (modulated or DCLS) |
| Output amplitude: | 0 V to 10 V P-P (adjustable) |
| DC level shift: | TTL/CMOS |
| Timing functions | |
| Heartbeat (TTL, 50Ω): | Programmable periodic 2.3 mHz to 2.5 MHz |
| Time strobe (TTL, 50Ω): | Programmable, 1mS through hrs |
| Event capture (TTL, 50Ω): | 100 nS resolution, zero latency 1PPSpulserate(TTL, 50Ω): |
| Positive edge on-time | |
| Disciplined oscillator | |
| Frequency: | 10 MHz |
| Outputs (50): | 1, 5, or 10 MHz (selectable) |
| Rate accuracy | |
| Standard oven oscillator: | 2.0E-9 short term (tracking) |
| 5.0E-8/day long term (flywheeling) | |
| Sync sources: | Time code, 1PPS |
| VME Bus | |
| Size: | 6Ux160 mm; B size, single |
| Address space: | A16, AM codes $29 and $2D, 64 bytes |
| Data transfer: | D16 |
| Interrupter: | D08(O), I(1-7), ROAK |
| Power: | +5 VDC @ 1.5 A |
| +12 VDC @ 50 mA | |
| +12 VDC @ 250 mA (GPS) | |
| -12 VDC @ 30 mA | |
| Environment | |
| Temperature | Module |
| Operating: | 0°C to 70°C |
| Storage: | -50°C to 125°C |
| Humidity | |
| Operating: | 5% to 95%* |
| *non-condensing |
 VME635091-SyncClock |
Product Data Sheet |
