Microsemi SA.22c, Руководство пользователя

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SA.22c Rubidium Oscillator
Designer Reference and User Guide Revision D 2
2 Overview
This section describes the SA.22c and lists its typical applications. It provides information on dimensions,
performance, and connector pinouts.
The SA.22c is a small form factor, lamp-based Rubidium (Rb) oscillator, as shown in the following figure.
This fifth-generation Rb oscillator reflects significant advances in physics miniaturization and integration.
Figure 1 • SA.22c Rubidium Oscillator
The SA.22c design is refined for low-cost mass production and can be integrated into time, frequency,
and synchronization systems. It can be directly mounted on a circuit board as a component of a module.
2.1 Applications
The wide operating temperature range of the SA.22c sets a new high-point for this type of atomic
reference. Compared with traditional quartz oscillators, the stability of the SA.22c allows it to maintain
excellent frequency control, even when the base plate temperature goes above 75 °C. When the host
system overheats in fault mode, the SA.22c oscillator continues to produce a stable and accurate time
along with a frequency reference.
The SA.22c can be integrated into time and frequency systems, it operates on low power (10 W at 25 °C,
operating).
The design is successfully applied as an OEM component in wireless telecom networks such as digital
cellular/PCS base stations and SONET/ SDH digital network timing. When linked with a GPS receiver or
other external timing reference, the SA.22c provides the necessary timing requirements for CDMA
cellular and PCS systems. The low temperature coefficient and frequency stability extends the holdover
performance when the GPS signal is lost. Temperature compensated units are available for those special
applications that require better temperature performance.
The SA.22c produces a stable frequency with good short and long term stability and phase noise
performance.
The microprocessor-based SA.22c allows serial command selection and enables TTL-level digital output
frequencies that divide the oscillator output to a number of different frequencies compared to a single
fixed output frequency of older oscillators. The ACMOS output frequency is selected at the time of
order.
A 1PPS output is an integral part of the design. An optional 1PPS input allows the unit to track GPS or