Copying a capacitance-change curve into a voltage-limit cell is the wrong record, and that mix can damage a part or leave a circuit short of capacitance. Separate the allowed voltage from the effective capacitance before either number is used.
This page is a reading record for three Murata documents retrieved on 11 October 2026. It does not draw a curve, name an ordering code, or approve a substitute part.
Read the axis before copying a number. A voltage-derating clause on Murata’s caution page is a voltage and temperature instruction for the products that clause names. A DC-bias chart shows how far capacitance moves from the nominal value as DC voltage rises, for the high-dielectric capacitors that FAQ names. The temperature-characteristics article measures capacitance change with temperature. If the ordering code, or the chart for that code, is missing, leave the cell blank.
- Name the horizontal axis and the vertical axis.
- Name the quantity the chart limits or reports: voltage, capacitance change, or a life estimate.
- Name the dielectric or product family the page assigns to that chart.
- Copy the temperature and the bias condition printed with that chart.
- Open the detailed specification for the ordering code in hand. This page has no ordering code.
The check sits on the components route. When the task is to keep each electrical value inside its own section of a device file, use the microcontroller datasheet condition checklist. A derating chart is not a substitution approval; that review stays on the obsolete-component replacement matrix.
| Check | What to write | Why it matters |
|---|---|---|
| Axis | Units on each axis, copied from the figure or its caption | Voltage on one axis is not capacitance on the other |
| Quantity | Allowed voltage, capacitance change, temperature coefficient, or life estimate | These are different measurements |
| Dielectric or family | The class the source assigns to that chart | A temperature-compensating note does not fill a high-dielectric cell |
| Temperature and bias | The condition printed beside that chart | A 105°C clause is not a 150°C clause |
| Ordering-code file | The detailed specification for the part in hand, or blank | This page does not supply a part number |
Which quantity does each Murata chart report?
Murata’s caution page and Murata’s DC-bias FAQ do not describe the same plot.
The caution page, retrieved 11 October 2026, is a set of voltage and temperature instructions. Several clauses point to a figure or to the detailed specifications sheet. The FAQ, retrieved the same day, describes a chart whose horizontal axis is the DC voltage applied to the capacitor, in volts, and whose vertical axis is the capacitance change ratio against the initial value. The temperature-characteristics article, final revision date 1 December 2023, describes capacitance change with operating temperature, as a temperature coefficient or a capacitance change rate.
Takeaway: Write the quantity in the cell before writing a number.
What do the caution-page clauses say when the figures are missing?
Murata’s caution page prints seven derating clauses, and the figures under those clauses were not in the text read on 11 October 2026. The allowed-voltage cells stay blank. The clauses are not one rule.
| Clause | What the 11 October 2026 text says | What stays blank |
|---|---|---|
| Derating 1 | The test voltage of these products is less than 150% of the rated voltage in the Endurance / High Temperature Operating Life Test. | Any operating voltage. This sentence is a test-voltage statement. |
| Derating 2 | When the product temperature exceeds 105°C, use the product within the voltage and temperature derated conditions in the figure. | The figure values. They were not in the text. |
| Derating 3 | Apply the derating curve according to the operating temperature, and refer to the detailed specifications sheet. | The curve. The text names the sheet and does not print the curve. |
| Derating 4 | When the product temperature exceeds 125°C, use the product within the voltage and temperature derated conditions in the figure. | The figure values. They were not in the text. |
| Derating 5 | When the product temperature exceeds 150°C, use the product within the voltage and temperature derated conditions in the figure. | The figure values. They were not in the text. |
| Derating 6 | When the product temperature exceeds 105°C, use the product within the voltage and temperature derated conditions in the figure. | The figure values. The 105°C words match clause 2, and the clause is still separate. |
| Derating 7 | The test voltage of these products is 100% of the rated voltage in the Endurance / High Temperature Operating Life Test. | Any operating voltage. This is not clause 1. |
The page then points to separate links for automotive infotainment/comfort equipment, automotive powertrain/safety equipment, and consumer equipment. Those linked pages were not opened. A consumer sentence does not move onto an automotive row.
For the products the page calls “These MLCC products”, the text says they are designed for a wide range of applications, ensuring durability of over 5 years use. That sentence is separate from the next one. Consumer-equipment-specific MLCC products, the page says, are designed so that the estimated useful life can be extended longer than 5 years under “80% of the rated voltage or less, Maximum operating temperature -20°C or less”. The page says the estimated useful life under actual operating conditions can be approximated from the chart. That chart’s numbers were not in the text, so they stay blank. Estimated useful life is defined there as the time when the cumulative failure rate of continuous use is 1%. The page says the data is for reference only and is not intended as a guarantee of the product lifetime.
Takeaway: Keep the 150% test-voltage sentence, the 100% test-voltage sentence, and the 80% consumer-life condition in separate rows.
What does DC bias change, and for which dielectric?
Murata’s FAQ says there are two types of ceramic capacitors: the high dielectric type and the temperature-compensating type. It says the capacitance may change from the nominal value when a DC voltage is applied, and it calls that the DC bias characteristic of high dielectric constant capacitors. One sentence writes the examples as “XR5, X6S, X7R, etc.” The next writes the high-dielectric examples as “B/X5R, R/X7R characteristic”. Copy the code from the ordering document. Do not repair either string from memory.
The same FAQ says the temperature-compensating type, written “C0G, etc.”, has no DC bias characteristic. Later it says temperature-compensation capacitors, written “CH, C0G characteristics, etc.”, use paraelectric ceramic as the main material, and that the capacitance does not change with DC voltage for that reason.
For the high-dielectric case, the FAQ says that, as shown in its chart, the larger the DC voltage applied, the more the effective capacitance is reduced. The chart’s plotted points were not in the text. The axis statement was in the text: horizontal, DC voltage in volts; vertical, capacitance change ratio against the initial value. The FAQ says the characteristics should be considered, and that whether the use is appropriate should be confirmed from actual conditions and actual equipment. It also says DC bias is commonly observed in high dielectric constant capacitors, not only in Murata products.
The mechanism paragraph names barium titanate, BaTiO3, as the principal component, and a Curie temperature of approx 125°C. It explains the drop as spontaneous polarization lining up with an applied DC field, so capacitance becomes lower than before the bias. That is Murata’s account of the mechanism. It is not a measurement of a part on a bench.
Takeaway: A DC-bias chart reports capacitance change. It does not set the allowed voltage.
What does the temperature article measure?
The article “What is the temperature characteristics of ceramic capacitors?” carries the date 15 October 2012 and a final revision date of 1 December 2023. It says the information was current as of publication and may differ from the latest information. The copy used here was retrieved on 11 October 2026.
Temperature characteristics, in that article, are the change of capacitance with operating temperature, expressed as a temperature coefficient or a capacitance change rate.
Class 1, temperature-compensating multilayer ceramic capacitors, uses a calcium zirconate-based dielectric whose capacitance varies almost linearly with temperature. The coefficient is in ppm/°C, which the article writes as 1/1,000,000 per 1°C. It says the coefficient is defined by Equation 1 from the capacitance C25 at the reference temperature and the capacitance CT at the category upper temperature. The equation itself was not in the text, so this page does not print a formula. The article uses the EIA reference temperature of 25°C and notes that the JIS reference is 20°C. It defines maximum operating temperature as, by design, the maximum ambient temperature, including self-heating of 20°C MAX, that allows continuous use. It says EIA specifies capacitance temperature factors ranging from 0 ppm/°C to -750 ppm/°C. That range is the article’s statement of the EIA span. It is not the coefficient of a named part. Figure 1 is described as an example; its plotted values were not in the text.
Class 2, high dielectric constant, uses barium titanate, and the article says the capacitance varies irregularly with temperature. The standard values are the maximum and minimum capacitance change rate inside the applied temperature range, relative to C25. Equation 2 was not in the text. The article says Murata defines capacity change as +10%/-30% in Code B1 and as no provisions in Code B3. Those are Murata’s definitions of those codes in this article. They are not a reading from a capacitor in hand. The article notes that a JIS excerpt may differ from the latest JIS standard. The excerpt tables were not copied here.
Takeaway: A temperature coefficient is a capacitance change with temperature. It is not the voltage limit on the caution page.
Where does the ordering code go?
The ordering code for the part in front of you is blank on this page. So are the rated voltage, the plotted DC-bias points, and the plotted voltage-temperature curve. Derating 3 on the caution page sends those values to the detailed specifications sheet.
| Field | Filled from the three Murata pages | Your ordering code |
|---|---|---|
| Ordering code | Blank | The code on the document in hand |
| Dielectric class | High-dielectric or temperature-compensating, only after the file names it | Blank until that file is open |
| Rated voltage | Not stated for a part | Blank |
| DC-bias plot | Axes only; points not in the FAQ text | Blank until that part’s chart is open |
| Voltage-temperature figure | Clause thresholds only; figure values not in the caution text | Blank |
| Temperature coefficient | The EIA span and the Code B1 and B3 definitions only | Blank for the part |
| Life estimate | The consumer-equipment sentence, and a chart that was not copied | Blank |
Nothing in these three documents says that a higher voltage rating restores the nominal capacitance. A higher rating is not a result recorded here.
Takeaway: If the ordering-code file is not in hand, every numeric cell for that part stays blank.
When this does not apply
The 11 October 2026 search sample included a one-page note titled “Derating Voltage for High Operating Temperature Operation Using Solid Aluminum Electrolytic Capacitors”. The publisher was not established from the extracted text, and the chart was not read. No aluminum-electrolytic voltage is copied here.
- Automotive caution links on the Murata page were not opened.
- Equation 1 and Equation 2 were named and were not printed in the text. This page has no general derating formula.
- SimSurfing is named in the FAQ and on the caution page as Murata software for product characteristics. No SimSurfing plot was copied.
- This page does not approve a substitute part.
Takeaway: A chart for another capacitor family, or a figure that was not opened, stays off the row.
Methods and sources
This page compiles three public Murata documents retrieved on 11 October 2026 and read from that copy on 14 October 2026. It reports no bench measurement and no life test. The DC-bias FAQ is Murata’s capacitor FAQ on capacitance change under DC voltage. The caution page is Murata’s ceramic-capacitor caution page; figure graphics were not in the extracted text, so curve values are omitted. The temperature article shows a final revision date of 1 December 2023. How this reference handles sources is set out in the editorial policy.
Related reading
- Microcontroller datasheet condition checklist — Use it to keep each electrical value inside the section that states it.
- Obsolete-component replacement matrix — Use it when the question is substitution, not how to read a capacitor chart.
- Components route — The reading route this record belongs to.
Next step: Open the detailed specification for the ordering code in hand. Write the axis, the quantity, the dielectric, and the temperature or bias condition from that file. If any of those is missing, leave the cell blank.
