TDK Electronics · TDK Europe

Capacitor Life And Rating Application (CLARA)

Find the Right Film Capacitor in Just a Few Clicks 

CLARA is an intuitive search-oriented simulation tool for TDK and EPCOS film capacitors. It helps designers to find the most suitable product for their application conditions in just a few clicks. Within the design tool specifications of different products and the performance of the products under customer-specific application conditions can be simulated easily. Additionally, CLARA allows to include personal notes during a search and it is directly linked to the TDK Product Center for sample requests or product inquiries.

*Expected lifetime is an estimation and it is not provided in case of excess of any of the given ratings or in case of products that have no given reliability or lifetime figures in the corresponding product data sheet.

The use of CLARA is subject to the terms and conditions of the License Agreement.

CLARA stores cookies on your computer, tablet, smart phone and other devices to process information technically essential for the operation of the program. Please see Use of Cookies for details. 

Application Overview

TDK CeraLink capacitors

Download Capacitor Life and Rating Application (CLARA) Presentation Manual here: Download Presentation Manual

Tool for power circuit designers using film capacitors 

  • Powerful parametric search based on capacitor parameters
  • Powerful simulation of given application conditions
  • Combination of both (search by simulation) in the Advance Search Application Based module

Indication of safety margins and limits

  • Returns the maximum allowed temperature at the target operation voltage
  • Returns the maximum allowed voltage at the target operation temperature
  • Thus providing more flexibility to the designers to adjust whatever is more convenient

Part characteristics

  • Download curves of ESR, IRMS vs. frequency, impedance, 3D step, spice models 

Part comparison

  • Up to 4 part numbers
  • By characteristics
  • By simulation of application conditions

Explore CLARA

Search and simulation

  • Parametric search of part numbers based on film capacitor parameters
  • Access to part numbers characteristics and download of useful information: STEP files, spice models, curves
  • Part number comparison of characteristics and adding personal notes
  • Simulation of application conditions, up to 4 part numbers at the same time

Refine search tips

  • Limiting by range, by tolerance value, by dimensions


  • Input of application conditions in the previous selected 4 part numbers
  • Mission profile with two load conditions in this example, up to 5 can be input
  • Harmonics with either IRMS or VRMS
  • Save conditions for later use
  • Description of input application parameters, results and safety index for every load condition
  • Example of waveforms with the correspondence to application parameters

Simulation knowing the part number

Two ways to access to the simulation module:

  • Option 1
    • Select simple search, input the part number (no need to be full part number), and select the part number from the list
    • Then select application & useful life simulation
  • Option 2
    • Select directly from CLARA home page, application & useful life simulation
    • Then input the part number with minimum 11 digits and select from the list
    • Restore application conditions from a previous saved file

Advanced search – application based

  • Simple search is executed based on capacitor parameters and not application paramaters
  • Advanced search is executed based on application parameters, combined optionally with capacitor parameters
  • 1. Circuit position, 2. External approval, 3. Capacitance, 4. Application, 5. Others
  • Runs automatic simulation on possible part numbers

Frequently Asked Questions

Simple search 

What happens if I do not insert the complete range of “From” and “To” values?

The results will comprise part numbers having the target capacitance value and the next available capacitance for the same or higher input voltage, ARMS, temperature, etc.

I have searched for two reference standards, automotive AEC Q-200D and EMI Suppression IEC 60384-14. Why are there also results with non-automotive product series?

The criteria checkbox for reference standard is OR, and therefore shows all results having AEC Q-200D OR IEC 60384-14. If you look for an X or Y capacitor with AEC Q-200D compliance, select the required class in “External Approval” and click the checkbox of AEC Q-200D in “Reference Standard.”

I did a search for a capacitor that can operate at 105 °C and 470 V DC. I inserted these values in “Simple Search”, and later when doing the simulation, I realized that the selected capacitor could not operate at 105 °C and 470 V DC. What is the reason for this unusable result?

“Simple Search” executes a search based on capacitor parameters and not application parameters. Suppose you insert 105 °C and 470 V DC. In that case, it will result in all part numbers having equal or higher temperature as maximum temperature AND all capacitors having equal or higher rated voltage than 470 V DC (Note: Rated Voltage is a parameter given usually at 85 °C).

“Advance Search Application Based” is the better module for this case. You can insert application parameters combined with some capacitor parameters.

Application Simulator 

Why does the Application Simulator not run if I enter the full part number?

Firstly, it is necessary to do a search, even with the full part number, and click search. On the list of part numbers, click the left check box of the desired part numbers and then click confirm. These are the selected ones for the simulation. You can repeat this process with other different part numbers up to a total of four parts. Then click “Simulate” when you want to access the simulation module.

Why do I not obtain lifetime results after a simulation?

There may be an over-rated condition above the given specification. Or the selected product is an EMI suppression capacitor. We do not provide lifetime statements for these EMI suppression capacitors because they are typically exposed to unexpected network disturbances that can make the lifetime statements no longer applicable.

What is the meaning of “Confidence Level”?

This is the reliability function for the given lifetime expectation. For example, 95% for a lifetime of 100,000 h, means that after this 100,000 h, at least 95% of the components could have survived the given conditions. For detailed information, refer to Data Book – General Information – Quality.

What is the exact meaning of the input application parameters?

Info buttons contain detailed information of the meaning of every parameter for better understanding. There is more information in the help file about waveform types and their conversion into input parameters.

Why do I not obtain lifetime results after a simulation?

There may be an over-rated condition above the given specification. Or the selected product is an EMI suppression capacitor. We do not provide lifetime statements for these EMI suppression capacitors because they are typically exposed to unexpected network disturbances that can make the lifetime statements no longer applicable.

If I input both operating AC sinusoidal (V RMS) and peak-to-peak voltage, and both are contradictory, which one is to be selected for simulation and thermal simulation?

The tool selects the worst case for the simulation of voltage stress. For thermal simulation, it is necessary to input the frequency harmonic spectrum; otherwise, it is assumed that there is no thermal stress beyond the input ambient temperature.

What if I input far above limits for operation conditions? (Such as 1000 kV or 1000 °C or -400 °C)

The models work under typical operation ranges. Out of this, they are not reliable or even not valid. They are estimated for the range of operation. In case of brief over-voltages or over-temperatures, we recommend checking the datasheet and/or contacting your sales channel for a customized feasibility check.

If the total A RMS (in any of the conditions) exceeds a certain value, the result always is typical self-heating exceeded. Why does the result not change if I decrease the ambient temperature (ºC)?

CLARA tool warns in case the self-heating is somehow higher than a certain given level. A very high self-heating could not necessarily harm the component if the ambient temperature is low enough and if there is no degradation of a parameter during the capacitor life that increases such a self-heating value.

Also, the self-heating estimation is based on our lab testing, with natural cooling and single capacitor test; no other heat source is considered that could influence a different Rth. We strongly recommend a real application test to monitor the key parameters (temperature, current, voltage, waveforms) for all cases, especially those where conditions are close to the limits.

What does “Operation above frequency” mean?

Every part number is characterized for a frequency range, which we consider to have a homogeneous current distribution in the winding element. Therefore, power losses and dissipation follow the given calculations. CLARA makes a simple extrapolation of the curves based on the latest two frequency points. Let’s have a closer look on what will happen above such a frequency in a real application: These cases should be carefully evaluated via FEA simulation and a real test regarding thermal losses and dissipation with specific boundary conditions in the PCB.

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