Silicon-based MEMS oscillators (microelectromechanical systems) are increasingly being used in electronics development. Higher quality requirements such as accuracy, temperature and long-term stability as well as new, smaller component sizes are the driving factors establishing these oscillators as a leading timing solution on the market. The leading supplier of such silicon-based, configurable MEMS oscillators is SiTime Inc.
MEMS-based timing solutions offer a variety of features that help users differentiate their products. These features include high flexibility in parameter setting, smaller sizes and exceptional reliability.
As a strategic partner of SiTime, Jauch Quartz GmbH offers a MEMS oscillator configuration service that can deliver customized oscillators with extremely short lead times.
This increases product availability and enables customers to act flexibly in the design phase, consolidate their supply chain and thus reduce operating costs and time to market.
The MEMS oscillator from SiTime is a complete clock generator. A MEMS resonator and a configurable CMOS ASIC are combined in one package. The ASIC contains a special, configurable PLL (phase-locked loop), temperature compensation, an OTP memory for the customer-specific configuration parameters, filters and voltage regulators. All these function blocks and the MEMS resonator are integrated in the same housing (figure 2).
While the quartz oscillator usually requires a quartz resonator manufactured to the corresponding oscillator frequency, the MEMS oscillator uses a standardized base resonator. Different output frequencies and other features are generated by the unique configuration of the PLL, described and stored in the integrated OTP memory. Parameters such as the slope of the square wave signal, the output driver strength, the supply voltage, the frequency stability and other options can be defined - depending on the oscillator type (e.g. XO, TCXO, VCXO, DCXO, OCXO and SSXO). This creates countless variation possibilities, adapted to the needs of the application.
This is illustrated below using the example of the AEC-Q100 MEMS blank “Blanks” SIT8924BA-71-XXX-000.FP000, a standard series MEMS oscillator in a tiny 2x1.6 mm² package for use in automotive applications in the extended temperature range. The code table for the part numbers is shown in figure 3. The flexibility is already apparent when looking at the possible output frequencies. The range of this oscillator extends from 1 MHz to 110 MHz with a setting accuracy of six decimal places. This feature alone results in over 100 million configuration variants, plus the multipliers by specifying “Frequency Stability”, “Temperature Range”, “Output Drive Strength”, “Feature Pin” and “Supply Voltage”.
Thanks to Jauch's individual configuration service for MEMS oscillators, the advantages of the setting options of SiTime oscillators can be fully utilized:
A wide range of MEMS oscillators can be manufactured and delivered for sampling and pre-series according to customer specifications at the company headquarters in Villingen-Schwenningen with delivery times of just 24 to 48 hours. Just six to eight weeks delivery time is required for the configuration of MEMS oscillators for normal series production.
The decisive advantage for the supply chain: short lead times: Particularly in times of allocation, component shortages and increased procurement times, the configurable architecture gains central importance in order to deliver at short notice and quickly replace “problem components”.
MEMS oscillators from SiTime are available from Jauch in six different product groups: MEMS oscillators for versatile use, differential oscillators, spread spectrum oscillators, MEMS OCXOs, TCXOs, AEC-Q100 qualified MEMS oscillators and particularly robust MEMS oscillators for use in aerospace & defense applications. The portfolio is rounded off by a range of clock buffers that support a wide range of frequencies, five standard input types and up to ten single-ended or 20 differential outputs.
published: 02.07.2024