Electronic Components Solutions

Syfer's Ultra-low ESR capacitors crafted for high frequency and RF power

Syfer's Ultra-low ESR capacitors crafted for high frequency and RF power

Designed specifically to meet the ever increasing power demands of RF applications such as telecoms PA systems, Syfer Technology has developed a range of RoHS compliant Multilayer Ceramic Chip Capacitors (MLCC) with ultra-low equivalent series resistance (ESR).


  • One of the most overlooked, but important, performance characteristics of a capacitor used in power circuits is its equivalent series resistance. It determines the capacitor's I2R heating losses, which in turn impacts the efficiency, pulse handling capability, and reliability of its associated circuit. ESR is Xc/Q so a capacitor with very low ESR will have a high Q or Quality factor. A theoretically perfect capacitor would have an ESR of zero, be lossless and therefore not self heat.

  • Optimized design

  • Developed and manufactured by Syfer, these passive devices provide an enhanced capability using the existing, very stable, High Q material system that provides excellent, low loss performance in systems to beyond 3GHz. ESR at 1GHz for a typical 10pF capacitor is below 0.1Ohms, demonstrating a significant improvement over standard High Q devices. Demand for low ESR capacitors is increasing as these passive components be used in higher power applications and can help reduce power consumption in battery-powered devices and RF power amplifiers. In addition, the better power handling of the capacitors can allow for downsizing or reduction in cooling considerations for existing technology. Syfer’s range includes case sizes of 0603, 0805 and 1111; over a capacitance range from 0.5pF to 240pF; rated voltages of 200, 250 and 500V and high self-resonant frequencies up to 10GHz. They are available with various termination options including copper barrier for non-magnetic applications.

  • Practice

  • Applications include telecommunications systems and other RF and microwave installations, particularly high power RF circuits, amplifier matching networks, filtering, diplexers and antenna matching. These high frequency MLCC’s are also suitable for many general purpose applications where economical, high performance is required, including High Q, DC blocking, VCO frequency stabilisation and bypass & coupling circuitry.

  • Main Advantages

    Ultra-low ESR
  • High working voltages, up to 500Vdc
  • High self-resonant frequencies
  • Capacitance range 0.5pF to 240pF
  • Case sizes 0603, 0805 and 1111

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    Syfer Technology Limited is dedicated to the manufacturing of multilayer ceramic components. It's comprehensive product range includes high volume ceramic chip capacitors through to application specific capacitor assemblies and highly complex planar arrays. Syfer also designs and manufacture a range of EMI filters including threaded and solder in panel-mounted styles as well as surface mount devices for pcb applications.

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