Electronic Components Solutions

Decoupling and filtering of RF Signals and noise

Decoupling and filtering of RF Signals and noise

The new V Series capacitors deliver increased broadband rejection in a significantly reduced footprint for bypass capacitor filtering networks.  Released under the DLI brand from Knowles Precision Devices, this cost-effective capacitor line is built on a compact 30 mil by 30 mil footprint.  This superior RF signal blocking design tool will solve the needs of design engineers looking to decouple RF signals from DC bias lines in active circuit designs, such as MMICs, or filter out noise from switching power supplies.

 

    Iy's more than just values

  • For designers looking to have broadband RF isolation, capacitors are the go-to components to complete the task. In practice, actual capacitors are modelled as a combination of capacitors, inductors, and resistors. At resonance the parasitic inductor and capacitor cancel out and an impedance low is realized. Above resonance the response of the inductor begins to dominate and cause the positive impedance slope. A common design rule is to consider 3 or 4 capacitors in shunt to ground, each with different values to provide broadband RF isolation. The end result is 3 or 4 capacitor curves superimposed, providing a broader frequency range of low resistive paths to ground for unwanted noise signals.

  • Application Recommendations (MMIC)

  • As an example the manufacturer of an MMIC is recommending ten (10) capacitors per MMIC to provide adequate grounding for DC supply lines. When taking such an approach one needs to consider the RF performance of the system as a whole. Rather than looking at the capacitor in isolation we should ask if the RF performance of the capacitors in practice is optimal for a design.

  • Measured Bypass Networks to verify performance

  • Using Measured Bypass Network results, DLI took the investigation one step further to consider what the performance of these devices could achieve in minimizing recurring harmonics from a hypothetical tone. To block frequencies below 100 MHz, they compared a traditional capacitor bypass network pulled from an industry datasheet (consisting of 3 capacitors ranging from pF to nFs), V-Series Capacitors, and a DLI UX series capacitor in combination with the V series part. They then ran a few different tones through the devices to simulate noise sources and compared the results. Once again, it is interesting to note that RF performance was not necessarily correlated to the choice of capacitor’s capacitance value, and verifying RF performance is the only way to guarantee performance.

  • Main Advantages

    High Capacitance Density
  • Up to 10nF in 30 mil square size
  • Up to 200WVDC for High Powered system needs
  • Can be epoxy or AuSn mounted

Related Solutions

  • Aluminum Electrolytic Capacitors vs. Film Capacitors

    The progress in semiconductor design sets the trend in current and future devices of power electronics: it manifests itself particularly in smaller dimensions, as well as in higher voltages and switching frequencies. Referring to intermediate circuit capacitors, this trend leads to aiming at higher energy densities and larger current loads, and – at the same time – decreasing space.

    Under these conditions, especially aluminum electrolytic capacitors and plastic film capacitors offer advantageous solutions. Jianghai has both technologies in the production program and this article gives an overview on the major differences between aluminum electrolytic capacitors and film capacitors.

  • Prudent use of electrolytic capacitors in vibrating applications

    The use of electrolytic capacitors in vibrating applications like motor controllers or power tools, must be considered very carefully regarding specific criteria.
    When you're designing electronic control applications or drives, you have to think about specifications like higher power and miniaturisation.
    If you're designing vibrating applications however, you should not forget to think about vibration resistance and temperature!

  • Miniaturization of HV applications: a solution for every Power Electronics Engineer

    StackiCap™ has been set to revolutionise the world of large, HV(200V – 2kV), X7R Multilayer Chip Capacitors (MLCCs)!

    It dramatically increases the max capacitance values within a size/voltage or can reduce chip sizes. They take up 1/10th of the current footprint dimension and save up to 9/10th of the weight of a stacked cap. The advantages are spectacular on any HV products where pcb space is at a premium and max. capacitance is required in a smaller footprint. Typical applications include power supplies, projector modules, lighting systems and throughout the aerospace sector.

Supplier

  • Dielectric Laboratories

    Dielectric Laboratories is a global supplier of microwave and millimeter wave components for optical and wireless communications, military, medical, semiconductor, aerospace, and transportation markets.
    DLI is a manufacturer of High-Q Multi-Layer capacitors (MLC) and Single-Layer capacitors (SLC), Resonators, Filters, Broadband DC blocks, Thin Film components, and Custom ceramic components. In 2004, DLI acquired Voltronics Corporation, a world leader in precision variable capacitors

Related Blog messages

  • Ceramic Technology offer 10nF Safety Certified MLCCs

    MLCC’s have been used in automotive applications for years, but the big change being seen is the voltage rating and size of components now being used.  This new revolution in MLCC technology, used in control electronics, is being driven by modern on-board charging systems - PHEV & EV where mains ac is involved.  Knowles brand Syfer has responded to demands by increasing its range of 250V ac X1/Y2 Safety Certified capacitors to 10nF.

  • Knowles Capacitors update

    In 2014 Dielectric Laboratories (DLI), Novacap, Syfer Technology and Voltronics came together into a single organisation, Knowles Capacitors. With a combined history exceeding 175 years, and operating as a division of Knowles Corporation of USA, Knowles Capacitors was a merging of some of the world’s leading speciality capacitor manufacturers. The Precision Devices division of Knowles is a $200m+ global manufacturer of precision capacitors, components and crystal oscillators.

  • IPDiA's Broadband Silicon Capacitor (BBSC) Product Line at 40 GHz

    The BBSC capacitor series from IPDiA provide superior broadband performance, stability and reliability for all broadband optoelectronics and high speed data systems. They provide broadband performances better than 0.4 dB of insertion loss up to 40 GHz, as well as very high stability of the capacitance over temperature (50 ppm/°C), voltage variation, and are highly reliable.

  • Knowles New "HiT" High Temperature Ceramic MLCs

    Knowles capacitor brands Novacap and Syfer Technology jointly announce the launch of a new range of high temperature MLC chip capacitors. The "HiT" range of MLCCs has an operating temperature range of -55 to +200ºC and are suitable for a variety of high temperature applications and offer tin over nickel terminations – not previously available.