Product Overview – Taiyo Yuden JMK212BJ475KK-T
JMK212BJ475KK-T from Taiyo Yuden is a multilayer ceramic capacitor (MLCC) with a nominal capacitance of 4.7 μF and a rated voltage of 6.3 V. The dielectric system is X5R, and the device is supplied in an 0805 (2012 metric) surface-mount package.
Key parameters of JMK212BJ475KK-T:
- Capacitance: 4.7 μF
- Capacitance tolerance: ±10% (denoted by “K” in the part code)
- Rated DC voltage: 6.3 V
- Dielectric: X5R
- Package size: 0805 (2012 metric)
- Construction: Ceramic multilayer, surface-mount
Within low-voltage digital and mixed-signal systems, JMK212BJ475KK-T can serve in roles such as local decoupling, small-signal filtering, and low-voltage bulk energy storage where a moderate capacitance value in a compact footprint is required.
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Electrical Characteristics of JMK212BJ475KK-T
JMK212BJ475KK-T offers 4.7 μF of capacitance at its reference conditions with a tolerance of ±10%. This tolerance defines the production spread around the nominal value, which is relevant when designing timing networks or filters that depend on specific impedance characteristics.
With a rated voltage of 6.3 V DC, JMK212BJ475KK-T is tailored to circuits whose operating voltage stays well within this limit. This typically includes:
- 1.2–5 V logic supplies
- 3.3 V and 5 V microcontroller or FPGA rails (with adequate design margin)
- Low-voltage analog bias or reference rails
When selecting JMK212BJ475KK-T, designers match the 6.3 V rating against worst-case system conditions, including supply tolerance and transient excursions. For example, on a 3.3 V rail that might see short overshoots up to around 4 V, the 6.3 V rating provides margin while maintaining compact size.
In many low-voltage rails, multiple JMK212BJ475KK-T capacitors can be paralleled to achieve higher total capacitance while spreading RMS ripple current and lowering effective impedance.
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3.
Dielectric and Temperature Performance of JMK212BJ475KK-T
The JMK212BJ475KK-T uses an X5R dielectric, which defines both its operating temperature range and its capacitance stability characteristics over temperature.
X5R dielectric properties for JMK212BJ475KK-T include:
- Operating temperature range: −55 °C to +85 °C (X5R standard)
- Capacitance change vs. temperature: within ±15% over the X5R temperature range (typical for X5R dielectrics)
In practice, JMK212BJ475KK-T maintains a relatively stable capacitance profile across typical ambient conditions encountered in consumer, computing, and office equipment. In real-world use, for example, a 4.7 μF JMK212BJ475KK-T placed near a processor might experience case temperatures from 25 °C up to 70 °C; over this band, the capacitance remains sufficiently close to nominal for decoupling and filtering functions.
As an X5R MLCC, JMK212BJ475KK-T is not intended to be a precision timing element but offers a combination of volumetric efficiency and reasonable stability that suits power decoupling and general-purpose bypass roles.
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4.
Package, Size, and Mounting Features of JMK212BJ475KK-T
JMK212BJ475KK-T is packaged in the 0805 (2012 metric) SMD format, which indicates approximate dimensions of:
- Length: 2.0 mm (metric 2012)
- Width: 1.25 mm (metric 2012, typical for 0805 class)
- Low profile for dense PCB layouts
The 0805 (2012 metric) footprint of JMK212BJ475KK-T supports:
- Automated SMT assembly using standard pick-and-place equipment
- Compatibility with commonly used 0805 pad patterns
- Placement in high-density designs, including mobile devices, compact industrial controllers, and consumer electronics
During PCB layout, JMK212BJ475KK-T can be positioned close to IC power pins to minimize loop inductance. Parallel placement of several JMK212BJ475KK-T capacitors along a rail is common practice to reduce impedance over a broad frequency range.
For reflow soldering, JMK212BJ475KK-T is used with standard thermal profiles for MLCCs, ensuring that temperature gradients and peak temperatures remain within the capacitor’s specified processing limits.
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5.
Typical Application Scenarios for JMK212BJ475KK-T
Given its 4.7 μF capacitance, 6.3 V rating, X5R dielectric, and 0805 size, JMK212BJ475KK-T is suitable for a series of typical roles in low-voltage electronic systems:
1) Local decoupling of digital ICs
On 1.8 V, 2.5 V, and 3.3 V rails feeding microcontrollers, DSPs, or FPGAs, one or more JMK212BJ475KK-T capacitors can be placed close to power pins to smooth transient current demand. For instance, a 3.3 V microcontroller may use a mix of 100 nF high-frequency capacitors and 4.7 μF JMK212BJ475KK-T units for mid-frequency and bulk decoupling.
2) Bulk capacitance on low-voltage rails
Near voltage regulators or DC-DC converter outputs, JMK212BJ475KK-T can contribute to overall output capacitance. On a 5 V to 3.3 V buck stage, multiple JMK212BJ475KK-T capacitors may be used in parallel to form part of the required output filter network.
3) Signal and bias filtering
In analog or mixed-signal sections, JMK212BJ475KK-T may be used in low-pass filters or to stabilize bias rails where moderate capacitance and compact size are preferred. For example, a 4.7 μF JMK212BJ475KK-T can be used to form a simple RC filter with a series resistor on a sensor reference rail.
4) General-purpose bypassing
Across low-voltage supply rails distributed around a PCB, JMK212BJ475KK-T can be used wherever a 4.7 μF capacitor provides a suitable bypass function. Its 0805 package allows placement between traces and around vias without occupying large board area.
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6.
Design-In Considerations for JMK212BJ475KK-T Selection
When integrating JMK212BJ475KK-T into a design, several selection aspects arise from its core parameters:
Voltage headroom
The 6.3 V rating of JMK212BJ475KK-T suggests use on rails that do not approach this limit under worst-case scenarios. For a 5 V rail, care is taken to ensure that line surges, tolerance, and transient behavior remain compatible with a 6.3 V rated capacitor. On 3.3 V and lower rails, JMK212BJ475KK-T typically offers a comfortable margin, making it suitable for densely packed digital boards.
Capacitance planning
With a nominal 4.7 μF value and ±10% tolerance, JMK212BJ475KK-T is often combined with lower-value capacitors to achieve broadband decoupling. For instance, a regulator output might use:
- Several 4.7 μF JMK212BJ475KK-T units for mid-frequency energy storage
- Smaller 0.1 μF capacitors for high-frequency transient suppression
Board footprint and placement
The 0805 size of JMK212BJ475KK-T influences routing and mechanical clearances. The compact footprint allows designers to place multiple capacitors near critical ICs, with short traces that limit parasitic inductance. This layout strategy is beneficial in systems where fast digital edges demand stable local supply behavior.
Thermal and environmental operating window
With X5R dielectric, JMK212BJ475KK-T is designed for operation from −55 °C to +85 °C (X5R standard range). This suits equipment such as office electronics, computing devices, and controlled-environment industrial modules. In designs approaching the upper end of the temperature range, the capacitance variation characteristics of X5R are taken into account when establishing decoupling or filter margins.
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7.
Reliability and Quality Aspects of JMK212BJ475KK-T
The JMK212BJ475KK-T multilayer ceramic construction, X5R dielectric system, and 0805 package collectively form a mainstream, widely adopted device type. In real applications, such as embedded control units or communication interfaces, similar 4.7 μF / 6.3 V X5R 0805 capacitors are used throughout production systems for power integrity and general bypassing.
The consistent electrical specification of JMK212BJ475KK-T enables repeatable behavior when multiple units are used across a board, a factor that simplifies validation and maintenance of system-level performance across production batches.
Additionally, the ceramic material and surface-mount construction of JMK212BJ475KK-T align with standard SMT assembly and inspection processes, including automated optical inspection of the 0805 footprint and solder joints.
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Conclusion – Positioning JMK212BJ475KK-T in Component Selection
Taiyo Yuden’s JMK212BJ475KK-T combines 4.7 μF capacitance, 6.3 V rated voltage, X5R dielectric, and an 0805 (2012 metric) surface-mount package, forming a versatile MLCC for low-voltage electronic systems. Its electrical ratings align with the needs of 1.2–5 V supply rails, while the 0805 footprint supports dense PCB layouts and standard SMT processes.
In decoupling, bypassing, filtering, and low-voltage bulk storage applications, JMK212BJ475KK-T offers a well-balanced feature set. When used with appropriate voltage headroom and within the X5R operating temperature range, it can contribute to stable power delivery and signal integrity across a wide range of circuit topologies.
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Frequently Asked Questions (FAQ)
- Q1. What are the core electrical specifications of the JMK212BJ475KK-T capacitor?
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- A1. JMK212BJ475KK-T is a 4.7 μF multilayer ceramic capacitor with a rated voltage of 6.3 V DC. It uses an X5R dielectric and has a capacitance tolerance of ±10%. The device is supplied in an 0805 (2012 metric) surface-mount package.
- Q2. For which voltage rails is JMK212BJ475KK-T best suited?
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- A2. With a 6.3 V rating, JMK212BJ475KK-T is suited to low-voltage rails such as 1.2 V, 1.8 V, 2.5 V, 3.3 V, and carefully designed 5 V systems where maximum voltage, including tolerances and transients, remains within the 6.3 V rating. It is widely applicable to core and I/O supplies of digital ICs, low-voltage analog rails, and bias lines.
- Q3. What does the X5R dielectric of JMK212BJ475KK-T imply in practical use?
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- A3. The X5R dielectric indicates that JMK212BJ475KK-T is designed to operate from −55 °C to +85 °C, with capacitance variation typically within ±15% over that temperature range. This provides relatively stable capacitance for general decoupling, bypassing, and filtering functions in low-voltage electronics.
- Q4. What does the “K” in JMK212BJ475KK-T indicate?
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- A4. In the JMK212BJ475KK-T part number, “K” denotes a capacitance tolerance of ±10%. This means the actual capacitance will be within ±10% of the nominal 4.7 μF value under the specified measurement conditions.
- Q5. What is the package size of JMK212BJ475KK-T, and how does it affect PCB layout?
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- A5. JMK212BJ475KK-T is in an 0805 (2012 metric) package. This compact footprint allows close placement to IC power pins and supports high component density. Designers can place multiple JMK212BJ475KK-T capacitors in parallel along supply rails to lower impedance without consuming large board area.
- Q6. Can JMK212BJ475KK-T be used as a bulk capacitor near voltage regulators?
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- A6. Yes. JMK212BJ475KK-T, with its 4.7 μF capacitance and 6.3 V rating, is suitable as part of the output capacitance of low-voltage regulators and DC-DC converters. Multiple JMK212BJ475KK-T capacitors can be paralleled to achieve the total required capacitance and ripple performance, especially on 1.8–3.3 V rails.
- Q7. Is JMK212BJ475KK-T appropriate for decoupling high-speed digital ICs?
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- A7. JMK212BJ475KK-T is frequently used for decoupling high-speed digital ICs on low-voltage rails. It can be combined with smaller-value capacitors (for example 0.1 μF) to cover a broad frequency range, providing both bulk and mid-frequency decoupling close to IC supply pins.
- Q8. In what types of end equipment can JMK212BJ475KK-T typically be used?
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- A8. JMK212BJ475KK-T is suited for a wide spectrum of low-voltage equipment, including computing boards, consumer electronics, embedded control units, communications interfaces, and general-purpose control circuits. Anywhere a 4.7 μF / 6.3 V X5R 0805 capacitor is appropriate, JMK212BJ475KK-T can be considered.
- Q9. How does the temperature performance of JMK212BJ475KK-T affect design margins?
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- A9. Being an X5R capacitor, JMK212BJ475KK-T maintains capacitance within a typical ±15% range over −55 °C to +85 °C. When designing decoupling networks or filters, this temperature-dependent variation is included in the margin calculations, ensuring that the system performs as intended across its operating temperature range.
- Q10. Can multiple JMK212BJ475KK-T capacitors be paralleled, and what is the benefit?
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- A10. Multiple JMK212BJ475KK-T capacitors can be connected in parallel to increase total capacitance and reduce effective impedance on a supply rail. This also helps distribute RMS current among devices and can improve transient response, a common strategy on high-current low-voltage rails.
- Q11. Does the 0805 (2012 metric) form factor of JMK212BJ475KK-T fit standard SMT assembly processes?
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- A11. Yes. The 0805 (2012 metric) package of JMK212BJ475KK-T is fully compatible with standard SMT pick-and-place equipment and reflow soldering profiles used in modern PCB assembly. This form factor is widely supported in CAD libraries and manufacturing lines.
- Q12. Is JMK212BJ475KK-T suitable for use in mixed-signal circuits where analog and digital sections share supplies?
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- A12. JMK212BJ475KK-T is suitable for mixed-signal circuits as a general decoupling and bypass capacitor on shared or separate analog and digital rails. Its 4.7 μF value provides effective local energy storage and supply smoothing, which can help maintain supply stability for both analog and digital domains when used with appropriate layout and grounding practices.
