Wire-wound Chip Power Inductors (CB series) # CBC3225T4R7MR Multilayer Ceramic Capacitor (MLCC) Technical Document
Manufacturer : TAIYO YUDEN
## 1. Application Scenarios
### Typical Use Cases
The CBC3225T4R7MR is a 4.7µF multilayer ceramic capacitor in a 3225 package (3.2mm × 2.5mm) designed for high-performance applications requiring stable capacitance and low equivalent series resistance (ESR).
Primary Applications:
- Power Supply Decoupling : Excellent for high-frequency noise suppression in switching power supplies and voltage regulators
- DC-DC Converter Filtering : Provides effective ripple current handling in buck/boost converters operating at frequencies up to 1MHz
- RF Circuit Bypassing : Serves as high-frequency bypass capacitor for RF amplifiers and transceivers
- Signal Coupling : AC coupling in high-speed digital interfaces and analog signal paths
### Industry Applications
- Telecommunications : Base station power systems, network equipment power management
- Automotive Electronics : Engine control units (ECUs), infotainment systems, ADAS modules
- Consumer Electronics : Smartphones, tablets, gaming consoles, IoT devices
- Industrial Automation : PLCs, motor drives, power distribution systems
- Medical Equipment : Portable medical devices, diagnostic equipment power supplies
### Practical Advantages and Limitations
Advantages:
- High Capacitance Density : 4.7µF in compact 3225 package enables space-constrained designs
- Low ESR : Typically <10mΩ at 100kHz, reducing power losses and improving efficiency
- High Ripple Current Capability : Up to 1.5A RMS at 100kHz, suitable for power applications
- Stable Performance : X7R dielectric provides stable capacitance over -55°C to +125°C temperature range
- RoHS Compliance : Meets environmental regulations for lead-free manufacturing
Limitations:
- DC Bias Effect : Capacitance decreases with applied DC voltage (typically 30-50% reduction at rated voltage)
- Temperature Dependence : X7R dielectric exhibits ±15% capacitance variation over temperature range
- Voltage Coefficient : Performance varies with operating voltage, requiring derating in high-voltage applications
- Mechanical Stress Sensitivity : Susceptible to capacitance shifts under board flexure or mechanical stress
## 2. Design Considerations
### Common Design Pitfalls and Solutions
Pitfall 1: DC Bias Underestimation
- Issue : Designers often overlook capacitance reduction under DC bias
- Solution : Select capacitors with 50-100% higher nominal capacitance than required, or use multiple capacitors in parallel
Pitfall 2: Thermal Management Neglect
- Issue : Self-heating from ripple current can reduce lifespan
- Solution : Ensure adequate airflow and consider thermal vias in PCB layout for heat dissipation
Pitfall 3: Mechanical Stress
- Issue : Board flexure during assembly or operation causes microcracks
- Solution : Place capacitors away from board edges and mounting holes; use symmetric placement
### Compatibility Issues with Other Components
Voltage Regulator Compatibility:
- Compatible with most LDOs and switching regulators up to 25V
- Ensure voltage rating exceeds maximum expected voltage by 20-50%
- Watch for resonance issues when used with electrolytic capacitors in parallel
Digital IC Compatibility:
- Excellent for decoupling high-speed processors and FPGAs
- May require smaller value capacitors (100nF-1µF) in parallel for broader frequency coverage
- Consider ESL when used with BGA packages
### PCB Layout Recommendations
Placement Strategy:
- Position as close as possible to power pins of ICs (≤5mm ideal)
- Use multiple
