Top Five Reasons to Replace your Quartz Oscillator

A quartz oscillator (also known as a crystal oscillator) has been the reference clock of choice in the electronics industry for many decades. Recently, this legacy device has been under attack by a host of clock devices that use a newer, more advanced technology – Silicon MEMS. Here are the Top Five reasons why you should replace your quartz oscillator with a Silicon MEMS device.

1. Higher Performance:  
Silicon MEMS oscillators offer higher performance across a wide spectrum of parameters. A quartz oscillator has been optimized for specific parameters – such as phase noise at a particular frequency and operating voltage and does extremely well. Silicon MEMS oscillators not only perform extremely well on these specific parameters – but they also offer high performance other parameters, such as:

a. Stable and reliable startup over temperature (which is an inherent problem in quartz oscillators due to the activity dips of crystals)
b. Full frequency range available at 1.8V, which is not commonly available from quartz devices
c. Oscillator stability as good as 10 PPM, which is not commonly available from quartz devices (MEMS TCXOs offer stability as good as 0.1 PPM)

2. More Features:  
Silicon MEMS oscillators offer many more features than a quartz oscillator.  Some of these features are listed below

a. Any frequency, up to 6 decimal places of accuracy. This capability is useful for generating higher performance or lower error rates from systems.
b. Drive strength control for better impedance matching, ability to drive multiple loads, or reduced EMI.
c. Thinner packages for thinner electronics.
d. Operation at custom voltages between 2.5V and 3.3V.

3. Better availability:
Production lead times of Silicon MEMS oscillators are 3-5 weeks, while that of a quartz oscillator is 6 – 16 weeks. This reduction of lead time ensures that Silicon MEMS oscillators can reduce inventory and cost of ownership.

4. Better robustness and reliability:
Silicon MEMS oscillators are based on Silicon, and use no quartz. They offer 10 times more robustness (ability to withstand shock and vibration) than quartz oscillators, as well as ten times better reliability.

5. Better cost trajectory:
Silicon MEMS oscillators have a better cost trajectory than quartz oscillators because they are based on Silicon and leverage the semiconductor industry infrastructure.

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Learn more about :- differential oscillator ,  Voltage Controlled Oscillator

The Unique Features and Benefits of Silicon MEMS Differential Oscillators

A differential oscillator is used as reference timing sources in very high performance electronic systems. Typically, differential oscillators have a frequency in excess of 100 MHz, though frequencies below that are also occasionally used.

 There are a couple of reasons why differential oscillators are used in electronic systems. First – a differential output eliminates common mode noise, which is important in very high performance, high-speed systems. Another reason for using a differential oscillator is that it offers more robustness against power supply noise – and therefore, offers a higher Power Supply Rejection Ratio (PSRR). These two capabilities are especially useful in serial data protocols that transfer data in excess of 6 Gigabits per second.

 Historically, a differential oscillator is made of a quartz resonator, married to a fixed frequency analog circuit (oscillator). The quartz resonator operates in either fundamental or overtone mode, and generates resonance at the target frequency of oscillation. The clock output from the oscillator goes through output conditioning, and appears as LVPECL, LVDS, CML or HCSL outputs on the device. LVPECL and LVDS are the most popular signaling standards in differential oscillators, with LVDS getting more adoption in the recent past because of its lower power consumption.

 A Silicon MEMS differential oscillator uses a MEMS resonator operating at a fundamental frequency of resonance, which is married to an analog circuit consisting of an oscillator, a PLL and various other functions. Most of the Silicon MEMS differential oscillators are programmable, i.e. their frequencies, voltages, stabilities, output signaling type and control pin can be configured exactly to the customer's specification. Because Silicon MEMS timing companies use the fabless semiconductor model, samples of these customized devices are available in less than a week, and production is available in 3-5 weeks, both of which are very important for accelerating time to revenue.

 Another unique advantage of Silicon MEMS differential oscillators is its ability to offer very high frequencies and stabilities at very low voltages, without resorting to overtone and SAW technology. Therefore, they eliminate the startup issues that are associated with overtone oscillators, and they offer significantly better stability than SAW oscillators, as low as 10 PPM, which is not available from SAW. In addition, their aging is also significantly better than SAW oscillators.

 With all these benefits, it's no wonder that Silicon MEMS differential oscillators are gaining significant traction against quartz oscillators and are replacing the latter in storage, networking and telecom applications.

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Learn more about :- Voltage Controlled Oscillator , TCXO , Crystal Oscillator