From wristwatches to atomic clocks: experts in accurate and low-power timekeeping devices

CSEM's cutting-edge timing solutions for superior accuracy and power efficiency.

Abstract illustration representing timing solutions

In integrated circuit design, timing devices are used to provide accurate clocks and synthesizing frequencies. These devices play a vital role in almost all electronic systems, from microprocessors to communications. At CSEM, our expertise in timing technology spans several key areas:

  • Precise low-power timekeeping
  • Low-noise oscillators design
  • Atomic clocks
  • MEMS-based timing and frequency generation

Precise low-power timekeeping

Typical block diagram of a real-time clock integrated circuitTypical block diagram of an RTC integrated circuit

CSEM, in collaboration with leading industrial players, has co-developed today’s state-of-the-art 32kHz Real-Time Clocks (RTCs) that measure time with a maximum inaccuracy of 30s per year (1ppm). These clocks consume as low as 150nA and are integrated into millimeter-sized packages. Our energy-efficient designs can run on tiny batteries or achieve energy autonomy when combined with micropower energy harvesters, reducing your maintenance and operational costs and environmental footprint. This enables huge power savings by scheduling the activity of the higher-level system in which it is used, allowing it to operate intermittently and thus sleep most of the time.

Low-noise oscillators

Phase noise (PN) measured in a phase-locked loop (PLL) and a crystal oscillator (XO) designed at CSEMExample of phase noise (PN) measured in a phase-locked loop (PLL) and a crystal oscillator (XO) designed at CSEM.

In addition to accuracy, another critical metric for timing devices is the variability of consecutive time intervals, known as timing jitter. At CSEM, we meticulously engineer noise of oscillators, that are associated to jitter, to minimize power consumption while optimizing system performance and predictability. Timing jitter represents the statistical spread of the duration of a time interval or its repeatability. In electronic applications, this variability leads to imprecisions or errors. For example, a nanosecond inaccuracy translates into an error of thirty centimeters in distance measurements at the speed of light, such as in a ranging application for secure keyless entry in cars. In high-speed sensor interfaces, it could limit the resolution of the analog (or physical) to digital converters by sampling the signal too early or too late, recording a wrong signal level and introducing distortion.

Atomic clocks

For applications requiring synchronization or accuracy over longer periods, such as high-end terrestrial or airborne telecom, the use of standard quartz crystal oscillators is not sufficient. So to solve this issue, we have developed one of the world's most compact chip-scale atomic clock. This clock uses electronic transitions of atoms such as Rubidium or Cesium for improved long-term stability. It features a miniature MEMS-based physics package and a dedicated integrated circuit driver operating at 3.417GHz.

MEMS-based timing and frequency generation

You can also leverage the latest advancements in silicon micro-machining with our competitive MEMS-based oscillators. Enhance your products with our compact, cost-effective solutions, tailor-made to meet your specific industry needs. Our MEMS solutions serve as alternatives to quartz crystal oscillators, offering advantages in size and cost. And today, CSEM is recognized as a worldwide leader in this field, regularly contributing to industrial innovations. For instance, we designed a 32.768kHz clock with ±10ppm frequency stability over 0-50°C, based on an uncompensated 966kHz silicon resonator with -28ppm/°C initial frequency drift.

Ready to transform your next design?

CSEM is your partner of choice given our excellent track record in providing low-power, accurate timing solutions. We are eager to tackle new challenges and propose optimized bespoke developments meeting your requirements. Be assured these will be carried out with professionalism and passion. Minimize imprecisions and errors in your electronic applications with our advanced timing solutions, ensuring high reliability and accuracy in your critical operations.

To probe further

CSEM scientific and technical reports

Selected Publications in Conferences and Journals