560-5155 TrueTime 1/5/10 MHz Frequency Synthesizer

The Microchip / True Time 56000 Modular Time and Frequency Distribution System is a versatile Data Rate Clock (DRC) and Distribution System supporting an extensive variety of input references, oscillators, output frequencies, input/output interface styles, powerful network based management tools, and complete power supply plans. The modular architecture supports various clock rates and frequencies required in today's sophisticated communications applications.

The 56000 backplane can accept 1, or 10 MHz; IRIG B time code; and any TTL signal from DC to 10Mbps. Multiple redundant external frequency references can be applied to a hitless switch (passive combiner) located on each frequency synthesizer circuit card. The hitless switch provides a glitch-free transition from one input source to another, ensuring reliable and disturbance-free outputs, even in the event of failure of one of the input sources. The frequency reference inputs can be replaced or enhanced by an on-board oscillator circuit card or an on-board GPS timing receiver. The oscillators are disciplined to either the input frequency or GPS. Using the oscillators in combination with external reference inputs provides various levels of redundancy. The oscillators also add holdover capability so that uninterrupted operation is maintained in the event of total failure of the reference input(s).

Model 56000 outputs can include distributed or generated clock signals, frequencies, Network Time Protocol, and IRIG B time code. N.1 clock rate generation from 1Hz to 25MPPS in 1 PPS steps is available in addition to N.8 clock rate generation from 8 KPPS to 8.192 MPPS in 8KPPS steps. Also available is a Telecommunications Interface that provides a variety of outputs and alarms common in today's telecommunications applications. The chassis is configured with front and rear plug-in cards. The front panel plug-in circuit cards perform the modular rate generation and distribution functions and are hot swappable. The rear panel interfaces are also implemented using plug-in cards with a wide variety of connector types and styles. Of the 21 card slots available, four are reserved for the power supply(s), and the balance can hold almost any combination of available circuit cards. The basic chassis includes power supply, power input module, fault monitoring CPU and a CPU interface module. There are 16 available card slots for the various synthesizer/ distributor cards. Additional 56000 systems can be daisychained using an optional on-board fiber optics transmitter and receiver pair. Large networks of time-frequency distribution can be constructed using the fiber optics link.