KAM21BR71H104KM

The KAM21BR71H104KM is an automotive-grade multi-layer ceramic capacitor from KYOCERA AVX’s KAM (Automotive MLCC) series. KYOCERA AVX’s KAM series is one of the industry’s most comprehensive automotive MLCC portfolios, designed and qualified to meet the stringent requirements of AEC-Q200 for passive components. The KAM part numbering system provides a wealth of information at a glance: KAM = Automotive MLCC series, 21 = 0805 case size, B = thickness code, R7 = X7R dielectric, 1H = 50V voltage rating, 104 = 100nF (10 × 10⁴ pF) capacitance, K = ±10% tolerance, and M = 13″ paper tape & reel packaging. This particular part delivers 0.1µF of capacitance at a 50V DC rating in a compact 0805 package, with X7R dielectric providing stable performance across the -55°C to +125°C automotive temperature range. The nickel-barrier termination system with tin plating ensures excellent solderability and long-term reliability. As a base metal electrode (BME) MLCC, it uses nickel internal electrodes — a cost-effective and reliable technology that has become the industry standard for high-volume MLCC production. The KAM21BR71H104KM is the same physical device as the 08055C104K4T4A part number, representing two different AVX ordering nomenclatures for the same product. KYOCERA AVX KAM series automotive MLCCs are trusted by automotive OEMs and Tier 1 suppliers worldwide for use in powertrain, body, safety, and infotainment systems.

Multi-layer ceramic capacitors (MLCCs) operate on the fundamental principle of the parallel-plate capacitor: capacitance C = ε × (A/d), where ε is the permittivity of the dielectric material, A is the area of the conductive plates, and d is the distance between plates. The KAM21BR71H104KM achieves its 0.1µF capacitance in a small 0805 package by stacking many thin layers of X7R ceramic dielectric alternating with conductive electrode layers — typically dozens to hundreds of layers depending on the capacitance value and voltage rating. The internal electrodes are made of nickel (base metal electrode, BME technology), which is co-fired with the ceramic dielectric in a carefully controlled reducing atmosphere to prevent oxidation of the nickel electrodes. The odd-numbered electrode layers connect to one external termination, and the even-numbered layers connect to the opposite termination, effectively creating multiple parallel capacitors that sum their capacitance values. X7R is a Class II barium titanate-based dielectric with a high dielectric constant (relative permittivity typically around 2000-4000), enabling high capacitance density. The X7R designation means: X = -55°C minimum, 7 = +125°C maximum, R = ±15% capacitance change over the temperature range. X7R capacitors do exhibit some degree of voltage coefficient (capacitance decreases with applied DC bias) and frequency dependence, which should be considered in circuit design. The external termination structure consists of a copper base layer (connecting to the internal electrodes), a nickel diffusion barrier layer, and an outer tin plating — providing both good solderability and protection against solder leaching during assembly.

The KAM21BR71H104KM is a two-terminal surface-mount MLCC:

• Termination Structure: Copper base + Nickel barrier + 100% Matte Tin plating (Ni/Sn)
• Polarity: Non-polar — MLCCs have no polarity and can be mounted in either orientation
• Mounting Method: Surface mount technology (SMT), reflow soldering compatible
• Package Code: Code 21 = 0805 case size (2.01mm × 1.25mm)
• Packaging: 13″ diameter paper tape & reel, 15,000 pieces per reel (M suffix)

Note: This MLCC is non-polarized. For printed circuit board design, follow IPC-7351 land pattern recommendations for 0805 components. Standard reflow soldering profiles per J-STD-020 are appropriate for this device.

• Engine and Powertrain Control: Used extensively in engine control units (ECU), transmission control modules, fuel injection systems, and emissions control modules where AEC-Q200 qualification and high reliability are required for under-hood applications
• Body Control and Interior Electronics: Deployed in body control modules, door control units, seat controllers, lighting modules, HVAC systems, and instrument clusters for power supply bypass, signal filtering, and timing functions
• Safety and Chassis Systems: Used in ABS/ESC modules, airbag control units, brake systems, steering systems, and ADAS sensor circuits where reliable operation is essential for vehicle safety functions
• Automotive Sensor Interfaces: Provides decoupling, filtering, and signal conditioning for the numerous automotive sensors including pressure sensors, temperature sensors, position sensors, and accelerometers
• Power Supply Decoupling/Bypass: Serves as local bypass capacitors for ICs and microcontrollers, providing transient current during switching events and reducing power supply noise — the most common MLCC application
• DC-DC Converters and Regulators: Used as input and output filter capacitors in switching DC-DC converters (buck, boost, buck-boost) and linear regulators for ripple reduction and energy storage
• Signal Filtering Networks: Implements RC, LC, and pi filters for analog signal conditioning, EMI/RFI filtering, and frequency response shaping in audio, sensor, and communication circuits
• Industrial and Telecom: Found in industrial control equipment, PLCs, motor drives, telecom infrastructure, and networking equipment requiring wide temperature range operation and high reliability