The KEMET R66CD4470CK6AK is a radial-leaded metallized polyester film capacitor designed for applications requiring stable capacitance, low losses, and reliable long-term performance in general-purpose analog and power circuits. This device combines the self-healing properties of metallized film construction with the cost-effectiveness and thermal stability inherent to polyester dielectric materials, making it well-suited for filtering, coupling, timing, and energy storage functions across consumer, industrial, and automotive electronics.
Constructed with metallized polyester film, the R66CD4470CK6AK leverages a dielectric system that offers a favorable balance between volumetric efficiency and electrical performance. Polyester film capacitors exhibit relatively stable capacitance over a wide temperature range, typically from -55°C to +105°C or +125°C depending on rated voltage, with predictable drift characteristics that facilitate circuit design in environments where moderate temperature cycling occurs. The metallized electrode structure enables self-healing behavior: when localized dielectric breakdown occurs due to overvoltage transients or manufacturing defects, the thin metal layer vaporizes around the fault zone, isolating the defect and allowing the capacitor to continue operating with minimal capacitance loss. This failure mode contrasts with foil-type capacitors, where a single puncture can lead to catastrophic short circuits, thereby enhancing circuit reliability and simplifying protection schemes in moderately stressed applications.
The radial lead configuration provides straightforward through-hole mounting on printed circuit boards, supporting both manual assembly and automated insertion processes. Radial packages are particularly advantageous in retrofit designs, repair scenarios, and applications where board space permits vertical mounting, as the footprint remains compact while mechanical stability is maintained through dual-leg anchoring. The package also facilitates visual inspection and rework, considerations that remain relevant in prototyping, low-to-medium volume production, and field service contexts.
As a general-purpose film capacitor, the R66CD4470CK6AK is commonly deployed in AC line filtering, DC link smoothing, snubber networks, motor run applications, and audio signal coupling. In power supply designs, polyester film capacitors serve as input and output filter elements where ESR and ripple current handling are moderate, complementing electrolytic capacitors by providing low-inductance, low-loss energy storage. In motor drive and switching power circuits, these capacitors function as snubbers to clamp voltage spikes and reduce electromagnetic interference, benefiting from the film dielectric's high dV/dt tolerance and pulse-handling capability. Audio and instrumentation circuits utilize polyester film capacitors for their low distortion and stable impedance characteristics across audio frequencies, supporting signal integrity in coupling, equalization, and feedback networks.
The R66CD4470CK6AK carries an active product status and full RoHS3 compliance, ensuring availability for new designs and alignment with contemporary environmental regulations governing lead and restricted substances in electronic assemblies. The REACH Unaffected designation indicates that the product does not contain substances of very high concern at concentrations requiring special authorization, simplifying supply chain documentation and material declaration processes for EU and global markets. With an ECCN classification of EAR99, the component is generally not subject to stringent export controls, and the HTSUS code 8532.25.0010 identifies it under the harmonized tariff schedule for fixed capacitors, polyester dielectric type, facilitating customs clearance and tariff assessment.
Moisture sensitivity is not applicable, reflecting the hermetic or moisture-resistant construction typical of encapsulated film capacitors, which eliminates the need for baking or special dry-storage handling prior to soldering. This characteristic streamlines inventory management and manufacturing workflows, reducing the risk of moisture-induced failures such as popcorning or delamination during reflow or wave soldering processes.
When specifying the KEMET R66CD4470CK6AK, designers should verify that the capacitance value, voltage rating, and tolerance meet circuit requirements, particularly in applications where capacitance drift, dissipation factor, and insulation resistance influence performance. Polyester film capacitors typically exhibit dissipation factors in the range of 0.5% to 1.5% at 1 kHz, suitable for most general-purpose applications but less ideal for high-Q resonant circuits where polypropylene or polystyrene alternatives may be preferred. Voltage derating is advisable in high-reliability or elevated-temperature environments to extend service life and maintain capacitance stability; a derating factor of 50% to 70% of the rated voltage is common practice in industrial and automotive designs. Lead spacing, mounting height, and board layout should accommodate the radial package dimensions to prevent mechanical stress on solder joints and ensure adequate clearance for heat dissipation and high-voltage isolation where applicable.
Replacement Search Context for KEMET R66CD4470CK6AK Film Capacitor
When KEMET R66CD4470CK6AK is unavailable, under allocation, or being reviewed for cost reduction, the replacement choice should not be based only on capacitance value. A suitable alternative must match the electrical role of the original film capacitor, fit the PCB footprint, tolerate the same voltage and ripple environment, and maintain the expected reliability in the end application.
KEMET R66CD4470CK6AK is a radial metallized polyester film capacitor, commonly evaluated as a 47 nF-class replacement candidate in signal filtering, coupling, timing, suppression-adjacent low-energy circuits, and general-purpose analog designs. Potential equivalent or alternative part numbers include KEMET R82DC3470AA60K, WIMA MKS2C034701C00KSSD, TDK EPCOS B32529C0473K000, Vishay MKT1822447064, Panasonic ECQ-E2473KF, and Nichicon QYX1H473KTP.
The main challenge is that these parts may share the same nominal capacitance and dielectric type but differ in rated voltage, lead pitch, body size, tolerance, temperature behavior, lifecycle status, and availability. A practical KEMET R66CD4470CK6AK replacement should therefore be selected by checking both the circuit requirement and the physical constraints of the assembly.
What KEMET R66CD4470CK6AK Contributes to the Original Circuit
KEMET R66CD4470CK6AK is specified as a radial metallized polyester film capacitor supplied in Tape & Box packaging. It is RoHS3 compliant, REACH unaffected, active, and classified under ECCN EAR99. As a film capacitor, it is not moisture-sensitivity classified in the same way as many semiconductor packages, which simplifies handling compared with moisture-sensitive ICs.
Key engineering characteristics to verify before replacing it include:
| Parameter | KEMET R66CD4470CK6AK Engineering Relevance |
|---|---|
| Manufacturer | KEMET |
| Capacitor type | Metallized polyester film capacitor |
| Mounting style | Radial through-hole |
| Nominal capacitance | 47 nF class, based on the “4470” capacitance code convention |
| Tolerance | Typically evaluated as ±10% where “K” tolerance coding applies; confirm against the exact datasheet or body marking |
| Packaging | Tape & Box, suitable for automated or semi-automated insertion |
| Compliance | RoHS3 compliant, REACH unaffected |
| Product status | Active |
| Main replacement concern | Match capacitance, rated voltage, lead spacing, body size, dielectric behavior, and temperature range |
The polyester dielectric is often chosen where stable general-purpose capacitance, moderate size, and cost-effective film performance are needed. Compared with ceramic capacitors, polyester film parts usually provide lower voltage coefficient and more predictable capacitance under bias. Compared with polypropylene film capacitors, polyester parts are often smaller for the same capacitance and voltage rating, but may have higher dielectric losses.
Typical application areas include analog coupling networks, RC timing circuits, low-frequency filters, pulse shaping, general bypassing where film characteristics are preferred, and control electronics. In these uses, replacing KEMET R66CD4470CK6AK requires attention to more than the 47 nF value. A higher voltage-rated substitute may be acceptable if it fits mechanically, but a lower voltage part should not be used unless the circuit stress has been reviewed. A different lead pitch can require PCB rework, and a larger body may interfere with nearby components or enclosure clearance.
Engineering Review of KEMET R66CD4470CK6AK Equivalent and Alternative Part Numbers
The following table compares practical candidate replacements for KEMET R66CD4470CK6AK. Exact suitability depends on the original voltage rating, PCB pitch, maximum body envelope, and circuit stress conditions.
| Manufacturer | Part Number | Key Specifications | Product Features | Typical Applications | Why It Can Replace KEMET R66CD4470CK6AK | Main Differences or Limitations | Recommended Usage |
|---|---|---|---|---|---|---|---|
| KEMET | R82DC3470AA60K | Metallized polyester film capacitor, 47 nF class, radial leaded, ±10% class, general-purpose voltage range depending on suffix | Same manufacturer, polyester film construction, radial through-hole format | Coupling, filtering, timing, general signal conditioning | Closely aligned dielectric family and manufacturer design philosophy make it a natural first-source alternative | Exact voltage rating, lead pitch, and body size must be checked against the R66CD4470CK6AK drawing | Preferred when maintaining KEMET sourcing and similar film behavior is desired |
| WIMA | MKS2C034701C00KSSD | MKS2 metallized polyester, 0.047 µF, radial box film capacitor, commonly available in compact leaded formats | Compact box-style package, stable MKT behavior, well-known industrial film series | Analog filters, timing networks, coupling, control electronics | Same capacitance class and polyester film technology support functional substitution in many low- to medium-stress circuits | Body width and lead pitch may differ from KEMET R66 packaging; confirm rated voltage | Good option where compact size and broad distributor availability are priorities |
| TDK EPCOS | B32529C0473K000 | Metallized polyester film capacitor, 47 nF, ±10% class, radial leaded MKT family | Industrial-grade general-purpose film capacitor, established EPCOS construction | Signal filtering, low-energy pulse circuits, coupling and decoupling | Electrical behavior is similar for many general-purpose MKT applications | Mechanical outline may not match the original; voltage and pitch must be verified | Suitable for industrial designs that already qualify TDK EPCOS film capacitors |
| Vishay | MKT1822447064 | Metallized polyester film capacitor, 47 nF class, radial leaded, MKT series | Vishay film capacitor platform with broad use in general electronics | RC networks, filtering, coupling, control boards | Same dielectric family and capacitance class allow evaluation as a functional replacement | Ordering suffix affects voltage, tolerance, lead length, and packaging; verify complete datasheet | Useful when Vishay is an approved supplier or when availability is stronger than KEMET stock |
| Panasonic | ECQ-E2473KF | Metallized polyester film capacitor, 0.047 µF, ±10% class, radial leaded, often associated with higher voltage general-purpose use | Long-established Panasonic ECQ-E polyester film construction | Consumer electronics, audio coupling, filters, timing circuits | Capacitance and dielectric behavior are compatible in many signal-level applications | Lifecycle and availability should be checked; higher voltage versions may be physically larger | Consider for legacy designs or repairs where Panasonic ECQ-E footprint compatibility exists |
| Nichicon | QYX1H473KTP | Polyester film capacitor, 0.047 µF, ±10% class, radial leaded | General-purpose film capacitor with through-hole mounting | Filters, timing, coupling, low-frequency signal circuits | Same nominal capacitance and polyester dielectric support replacement evaluation | Mechanical size and lead pitch may differ; voltage rating must be equal to or higher than circuit requirement | Practical alternate source when Nichicon film capacitors are already qualified |
Among these options, KEMET R82DC3470AA60K is often the closest starting point because it keeps the sourcing within KEMET and remains within a similar metallized polyester film category. WIMA MKS2C034701C00KSSD and TDK EPCOS B32529C0473K000 are strong cross-reference candidates when the goal is reliable availability from widely used film capacitor families. Vishay MKT1822447064 and Nichicon QYX1H473KTP can be suitable when supplier qualification or procurement channels favor those brands. Panasonic ECQ-E2473KF may work well in legacy or repair contexts, but lifecycle status and dimensions should be reviewed before new design use.
Comparing KEMET R66CD4470CK6AK Replacement Options by Engineering Trade-Offs
A correct KEMET R66CD4470CK6AK alternative should be selected through a trade-off review rather than a direct capacitance-only match. The table below summarizes how the candidates differ in practical engineering terms.
| Evaluation Factor | KEMET R82DC3470AA60K | WIMA MKS2C034701C00KSSD | TDK EPCOS B32529C0473K000 | Vishay MKT1822447064 | Panasonic ECQ-E2473KF | Nichicon QYX1H473KTP |
|---|---|---|---|---|---|---|
| Electrical compatibility | Strong if voltage and tolerance match the original R66 part | Strong for 47 nF MKT replacement in signal circuits | Strong for general-purpose MKT circuits | Strong when the complete suffix confirms matching voltage and tolerance | Good if voltage rating is equal or higher; often physically larger at higher ratings | Good for standard 47 nF polyester applications |
| Mechanical compatibility | Likely closest among KEMET alternatives, but still requires pitch check | Compact package can help tight layouts, but pitch may differ | Requires PCB pitch and body height review | Depends on ordering suffix and series outline | May require more board space depending on voltage version | Check lead spacing and box size before substitution |
| Performance differences | Similar film behavior to original KEMET polyester capacitor | Good stability for MKT applications; compact construction | Industrial general-purpose film behavior | Comparable polyester performance; suffix-dependent construction details | Suitable for many analog uses; availability may vary | General-purpose polyester performance |
| Reliability considerations | Same-brand qualification may simplify approval | WIMA has strong reputation in film capacitor applications | EPCOS film capacitors are widely used in industrial electronics | Vishay offers broad film capacitor support | Older ECQ-E families may need lifecycle review | Suitable if current production and sourcing are confirmed |
| Package availability | Depends on distributor inventory and exact suffix | Often available through major component channels | Broad availability for common values | Broad but suffix-specific | Availability may be inconsistent for older references | Availability depends on regional stocking |
| Cost considerations | May be favorable if KEMET is already approved | Sometimes higher than commodity MKT parts, offset by availability and compact size | Competitive for industrial sourcing | Competitive with broad sourcing options | Cost may rise if sourced for repair or legacy builds | Often practical for alternate-source procurement |
| Best-fit scenario | First choice when replacing KEMET R66CD4470CK6AK while minimizing supplier change | Best when compact MKT capacitor availability is needed | Best for industrial control or general electronics with EPCOS approval | Best where Vishay is already qualified or easily sourced | Best for legacy equipment or Panasonic-qualified assemblies | Best as an alternate source for general-purpose radial polyester needs |
| Main limitation | Not automatically drop-in without voltage and footprint confirmation | May not match original body dimensions | Mechanical mismatch risk | Complete part suffix must be verified | Lifecycle and size concerns | Requires careful datasheet comparison |
For a low-frequency filter or timing circuit, capacitance tolerance and dielectric type usually drive the first screening step. KEMET R82DC3470AA60K, WIMA MKS2C034701C00KSSD, TDK EPCOS B32529C0473K000, Vishay MKT1822447064, and Nichicon QYX1H473KTP are all reasonable candidates if their voltage rating and package dimensions match the original design requirements.
For a board with limited component clearance, WIMA MKS2C034701C00KSSD may be attractive because compact box film capacitors are often easier to fit, but the lead pitch must match the PCB. For a design that prioritizes supplier continuity, KEMET R82DC3470AA60K should be reviewed first. For industrial equipment with approved-vendor constraints, TDK EPCOS B32529C0473K000 or Vishay MKT1822447064 may reduce qualification effort. For maintenance of older products, Panasonic ECQ-E2473KF can be considered if the exact footprint and availability are acceptable.
Before approving any KEMET R66CD4470CK6AK replacement, compare the original drawing with the substitute datasheet for capacitance, tolerance, DC voltage rating, AC/ripple limits where relevant, operating temperature, lead pitch, body dimensions, packaging format, and compliance status.
For quotations and sourcing support for KEMET R66CD4470CK6AK replacement parts, request pricing through IC-Components.com or email Info@IC-Components.com.
