The Microchip/Datum TTM635VME-VCXO is a VMEbus-based Time and Frequency Processor module delivering disciplined 10 MHz reference generation and multi-format time code processing. This 6U × 160 mm B-size module acquires time from IRIG B, 2137, and XR3 inputs, maintains precision timekeeping via battery-backed clock with +/-10 PPM accuracy, and generates synchronized IRIG B and IRIG H outputs. The voltage-controlled crystal oscillator provides a 100 nanosecond clock with flywheel operation during source loss. Multiple frequency outputs (1, 5, and 10 MHz), hardware-based time synchronization with zero latency, and event capture with 0.1 microsecond resolution make it suitable for applications requiring sub-microsecond timing accuracy and precise frequency references.
Technical Specifications
• Form Factor: B-size VMEbus module, 6U × 160 mm
• Oscillator: Disciplined VCXO, 10 MHz, 100 nanosecond clock
• Timekeeping: Battery-backed real-time clock, +/-10 PPM accuracy; flywheel operation on source loss
• Time Acquisition: IRIG B, 2137, XR3 time codes; freerunning mode; external 1 PPS; RTC
• Frequency Outputs: 1, 5, and 10 MHz; TTL/CMOS compatible; 80/20 duty cycle (5 & 10 MHz square wave)
• Time Code Generation: IRIG B (modulated and DC level shift) and IRIG H (DC level shift), synchronized to input source
• Time Code Decoding: IRIG B, 2137, XR3; input amplitude 1–5 V peak-to-peak; 10 kΩ AC/DC coupled impedance; ±50 ppm carrier range; 3:1 to 6:1 modulation ratio
• Time Synchronization: Zero-latency on-demand access (days through 0.1 microseconds) via hardware registers; programmable propagation delay compensation; leap second correction (GPS modes)
• Event Capture: Hardware-latching edge detection with time capture (0.1 microsecond resolution); maskable interrupt generation
• Strobe Output: Programmable coincidence strobe (hours through milliseconds); each-second mode programmable to milliseconds
• Interrupts: Five maskable sources; IRQ levels 1–7 programmable
• VMEbus Interface: Thirty-two D16 control registers
• Front Panel Display: Time-of-day LED (hours, minutes, seconds)
– Key Features
• Sub-microsecond time synchronization and event logging
• Multiple time code format support with automatic translation
• Disciplined oscillator maintains timing during source interruption
• Programmable periodic interrupt and strobe outputs
• TTL/CMOS compatible frequency distribution
– Typical Applications
• Precision timing distribution in VMEbus systems
• Time-stamped event logging and synchronization
• Multi-format time code conversion and generation
• Frequency reference for synchronous digital systems
– Compatibility & Integration
Designed for VMEbus systems. GPS upgrade options available on TTM637VME and TTM357VXI models.
