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Capacitor Review Q1 - 2011. Capacitance Offering by Technology. 1.0uF ~ 1000uF Common SMT Requirements. Ceramic (MLCCs) dominate lower range of capacitance values (0.5pF ~ 10uF) High Capacitance X5R MLCCs (Cap 10uF ~ 100uF)
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Capacitor Review Q1 - 2011
Capacitance Offering by Technology 1.0uF ~ 1000uF Common SMT Requirements • Ceramic (MLCCs) dominate lower range of capacitance values (0.5pF ~ 10uF) • High Capacitance X5R MLCCs (Cap 10uF ~ 100uF) • Film capacitors cover moderate cap range with increasing sizes with capacitance & voltage rating • Tantalum capacitors cover 0.1uF up to 1000uF in low VDC ratings • Aluminum E-Caps cover wide capacitance value range and supports higher VDC ratings. • Double layer capacitors (Farad values) in use for back-up and short term power applications
1uF ~ 2200uF / 2.5VDC ~ 100VDC SMT Capacitor Offering by Technology Use NIC QuickBUILDERTool to easily select & compare capacitors www.niccomp.com/quickbuilder/qb_capacitor.php
SMT Capacitor Technology Comparison SMT Flat-Chip Solid Aluminum Electrolytic SMT V-Chip Aluminum Electrolytic SMT Tantalum Electrolytic SMT MLCC Ceramic • Lowest Cost • High WVDC • Stability Over Voltage • Higher ESR • Wear-out (time & temperature) • Tallest – Largest Size SMT V-Chip Aluminum Electrolytic • Small Size • Stability Over Voltage • Stable over Time • Higher Cost • Shorting Failure Mode • Smallest Foot Print • Non-Polarized • Lowest ESR • Unstable over Voltage (VDC) • Unstable over Time (Aging) • Cracking = Short Failure Mode • Higher Cost – High CV SMT Tantalum Electrolytic • Low ESR - High RCR • Stability Over Voltage • Stable over Time • Higher Cost • Shorting Failure Mode SMT Flat-Chip Solid Aluminum Electrolytic SMT MLCC Ceramic
SMT Capacitor Sweet Spots Sweet Spots: Case Sizes & Tolerances: Trends - Suggestions • X5R dominates ≥1uF, X7R limited to higher VDC ratings • Avoid use of tolerances tighter than shown above • Use Alum E-caps over Tant E-caps in higher voltage (and transient risky) applications • Use film caps only when performance requirements warrant
Material Costs Trend: Tantalum E-Caps Tantalum Material Cost >200% increase over last 12 months Price Index 2009 2010
Capacitor Options • Suggestions to Mitigate Potential Tantalum Capacitor Issues: • … Price Increases and , or Shortages: • Plan and purchase as early as possible • Consider switch to reduced case size tantalum electrolytic capacitors as less price increase expected & larger production capacity in smaller case sizes • Consider use of liquid electrolyte aluminum electrolytic capacitors for high capacitance & high voltage (VDC) replacements; “V-Chip” • For large (D-V-E case sizes; 7343 size*) consider use of solid polymer aluminum electrolytic capacitors in same case size (* fit same PCB foot print & land pads) • Consider use of MLCCs (X5R) for low capacitance & low voltage replacements • Contact NIC to review your requirements [ NIC technical support tpmg@niccomp.com ]
MLCCs replacements For SMT Tantalum Capacitors • Please Note The Following: • High capacitance MLCCs (such as those listed below) will exhibit capacitance change with applied voltage, over temperature, over time and may exhibit piezoelectric properties not seen with tantalum electrolytic capacitors. • Please review your application with NIC technical support @ tpmg@niccomp.com • SMT Tantalum Cap Specifications: www.niccomp.com/catalog/ntct.pdf • X7R MLCC CapSpecifications:www.niccomp.com/catalog/nmc2.pdf Common 1.0uF C-V Sizes SMT MLCC Ceramic SMT Tantalum Electrolytic Replace With
Compare Capacitors www.niccomp.com/quickbuilder/qb_capacitor.php NIC QuickBUILDER Component selection and comparison tool /Provides comparison of different type capacitors Such as comparing tantalum electrolytic to aluminum electrolytic, or MLCC ceramic capacitors Example below shows 47uF, 10VDC comparison; MnO2 cathode tantalum, Polymer cathode tantalum & X5R ceramic MLCC
Need Help? Contact NIC to review your requirements [ NIC technical support tpmg@niccomp.com ]