www.avx.com AVX Multilayer Ceramic SMD Feedthru Capacitors Version 16.4 Feedthru 0805/1206 Capacitors Table of Contents W2F/W3F Series - 0805 & 1206 Feedthru Chips . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Tin/Lead L2F/L3F Series - 0805 & 1206 Feedthru Chips . . . . . . . . . . . . . . . . . . . 5 W2H - High Current Feedthru Capacitors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 W2F/W3F Series - Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 W2H Series - Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 W2F/W3F Series - Application Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 REV 01 Feedthru 0805/1206 Capacitors W2F/W3F Series GENERAL DESCRIPTION Available in both a standard 0805 and 1206 size, AVX’s line of feedthru capacitors are ideal choices for EMI suppression, broadband I/O filtering, or Vcc power line conditioning. The unique construction of a feedthru capacitor provides low parallel inductance and offers excellent decoupling capability for all high di/dt environments and provides significant noise reduction in digital circuits to <5 GHz. A large range of capacitor values are available in either NP0 or X7R ceramic dielectrics. AVX FeedThru filters are AEC Q200 qualified. High reliability screening options are available for spacecraft designs. W2F Series W3F Series 0805 1206 OUTPUT SIGNAL LINE - INPUT CAPACITOR VALUES GROUND Part Number W2F11A 220 8ATxx W2F11A 470 8ATxx W2F11A 101 8ATxx W2F11A 221 8ATxx W2F11A 471 8ATxx W2F15C 102 8ATxx W2F15C 222 8ATxx W2F15C 472 8ATxx W2F15C 103 8ATxx W2F15C 223 8ATxx W2F15C 473 8ATxx W3F11A 220 8ATxx W3F11A 470 8ATxx W3F11A 101 8ATxx W3F11A 221 8ATxx W3F11A 471 8ATxx W3F15C 102 8ATxx W3F15C 222 8ATxx W3F15C 472 8ATxx W3F15C 103 8ATxx W3F15C 223 8ATxx* W3F15C 473 8ATxx Size 0805 0805 0805 0805 0805 0805 0805 0805 0805 0805 0805 1206 1206 1206 1206 1206 1206 1206 1206 1206 1206 1206 Voltage 100V 100V 100V 100V 100V 50V 50V 50V 50V 50V 50V 100V 100V 100V 100V 100V 50V 50V 50V 50V 50V 50V Dielectric NP0 NP0 NP0 NP0 NP0 X7R X7R X7R X7R X7R X7R NP0 NP0 NP0 NP0 NP0 X7R X7R X7R X7R X7R X7R Capacitance 22pF 47pF 100pF 220pF 470pF 1000pF 2200pF 4700pF 10000pF 22000pF 47000pF 22pF 47pF 100pF 220pF 470pF 1000pF 2200pF 4700pF 10000pF 22000pF 47000pF PERFORMANCE CHARACTERISTICS NP0 X7R +50%, -20% +50%, -20% 100V 50V 300mA 300mA 1000MΩ 1000MΩ <0.6Ω <0.6Ω -55 to +125°C Capacitance Tolerance Voltage Rating Current Rating Insulation Resistance DC Resistance Operating Temperature Range HOW TO ORDER W 3 F Style Size Feedthru W = Plated Ni & Sn 2 = 0805 L = Plated SnPb 3 = 1206 1 5 C 223 8 A T 3 Number Voltage** Dielectric Capacitance Capacitance Failure Rate Termination Packaging Code Quantity of 1 = 100V A = NP0 Code Tolerance A = Not Applicable T = Plated Ni & Sn (Reel Size) Code Elements 5 = 50V C = X7R 8 = +50/-20% 4 = AUTOMOTIVE B = Plated SnPb 1 & 2 = 7" Reel (Pcs./Reel) Embossed Tape 3 & 4 = 13" Reel Embossed Tape *AECQ-200 Qualified. Contact factory for other values. **Note: NP0 available in 100V only and X7R available in 50V only. REV 01 A F = 1,000 A = 2,000, 4,000 or 10,000 1 Feedthru 0805/1206 Capacitors W2F/W3F Series Common Ground Feedthru Pad L S Feedthru Pad CL X BL T W EW BW Common Ground DIMENSIONS 0805 MM (in.) 1206 MM (in.) L 2.01 ± 0.20 (0.079 ± 0.008) 3.20 ± 0.20 (0.126 ± 0.008) W 1.25 ± 0.20 (0.049 ± 0.008) 1.60 ± 0.20 (0.063 ± 0.008) T 1.14 Max. (0.045 Max.) 1.27 Max. (0.050 Max.) BW BL 0.46 ± 0.10 0.18 + 0.25 -0.08 (0.018 ±0.004) (0.007 + 0.010 -0.003) 0.89 ± 0.10 0.18 + 0.25 -0.08 (0.035 ± 0.004) (0.007 + 0.010 -0.003) EW 0.25 ± 0.13 (0.010 ± 0.005) 0.38 ± 0.18 (0.015 ± 0.007) X 1.02 ± 0.10 (0.040 ± 0.004) 1.60 ± 0.10 (0.063 ± 0.004) S 0.23 ± 0.15 (0.009 ± 0.006) 0.46 ± 0.15 (0.018 ± 0.006) T P P S C W L RECOMMENDED SOLDER PAD LAYOUT (TYPICAL DIMENSIONS) 0805 MM (in.) 1206 MM (in.) T 3.45 (0.136) 4.54 (0.179) P 0.51 (0.020) 0.94 (0.037) S 0.76 (0.030) 1.02 (0.040) W 1.27 (0.050) 1.65 (0.065) L 1.02 (0.040) 1.09 (0.043) C 0.46 (0.018) 0.71 (0.028) TYPICAL FEEDTHRU CHIP CAP CONNECTION Physical Layout - A Feedthru Chip Component Model Ground Vcc or Signal Out Vcc or Signal In Signal Out Signal In Ground Ground The terminals are connected internally side to side. Left side and right side are connected and front and back are connected internally. For Decoupling, the chip is usually surrounded by four vias, two for Vcc and two for GND. For Signal Filtering, the in and out lines need to be separated on the circuit board. Physical Layout - B Ground Vcc Vcc Ground 2 REV 01 Feedthru 0805/1206 Capacitors W2F/W3F Series PERFORMANCE CHARACTERISTICS S21 0805 – 100V IMPEDANCE 0805 – 100V 0 10000 -10 1000 -30 -40 -50 -60 -70 1.E+05 W2F11A2208AT W2F11A4708AT W2F11A1018AT W2F11A2218AT W2F11A4718AT 1.E+06 100 |Z| (Ohms) S21 (dB) -20 10 1 0.1 1.E+07 1.E+08 1.E+09 0.01 1.E+05 1.E+10 W2F11A2208 W2F11A4708 W2F11A1018 W2F11A2218 W2F11A4718 1.E+06 Freq (0.3 MHz – 9 GHz) 10000 -10 1000 |Z| (Ohms) S21 (dB) -20 -30 -40 -70 1.E+05 W3F11A2208 W3F11A4708 W3F11A1018 W3F11A2218 1.E+06 1.E+08 1.E+10 100 10 1 0.1 1.E+07 1.E+09 IMPEDANCE 1206 – 100V 0 -60 1.E+08 Freq (0.3 MHz – 9 GHz) S21 1206 – 100V -50 1.E+07 1.E+09 0.01 1.E+05 1.E+10 W3F11A2208 W3F11A4708 W3F11A1018 W3F11A2218 1.E+06 Freq (0.3 MHz – 9 GHz) 1.E+07 1.E+08 1.E+09 1.E+10 Freq (0.3 MHz – 9 GHz) IMPEDANCE 1206 – 50V S21 1206 – 50V 1000 0 -10 100 |Z| (Ohms) S21 (dB) -20 -30 -40 -50 -60 -70 1.E+05 W3F15C2228 W3F15C4728 W3F15C1038 W3F15C2238 W3F15C4738 1.E+06 1 0.1 1.E+07 1.E+08 Freq (0.3 MHz – 9 GHz) REV 01 10 1.E+09 1.E+10 0.01 1.E+05 W3F15C2228 W3F15C4728 W3F15C1038 W3F15C2238 W3F15C4738 1.E+06 1.E+07 1.E+08 1.E+09 1.E+10 Freq (0.3 MHz – 9 GHz) 3 Feedthru 0805/1206 Capacitors W2F/W3F Series PERFORMANCE CHARACTERISTICS 0805 NP0 Current vs. Temperature Component Temperature (°C) 40.00 220pf 100pf 35.00 47pf 470pf 30.00 25.00 20.00 0.3 0.5 0.7 0.8 1.00 1.20 Current (A) 0805 X7R Current vs. Temperature 40.00 Component Temperature (°C) 1000pf 4700pf 2200pf 35.00 10nf 22nf 30.00 47nf 25.00 20.00 0.3 0.5 0.7 0.8 1.00 1.20 Current (A) 1206 NP0 Current vs. Temperature Component Temperature (°C) 40.00 100pf 22pf 47pf 470pf 220pf 20.00 0.00 0.3 0.5 0.75 0.87 1.00 1.20 Current (A) 1206 X7R Current vs. Temperature Component Temperature (°C) 40.00 1000pf 22,000pf 2200pf 20.00 0.00 0.3 0.5 0.75 0.87 1.00 1.20 Current (A) 4 REV 01 Feedthru 0805/1206 Tin/Lead Capacitors L2F/L3F Series GENERAL DESCRIPTION Available in both a standard 0805 and 1206 size, AVX’s line of feedthru capacitors are ideal choices for EMI suppression, broadband I/O filtering, or Vcc power line conditioning. The unique construction of a feedthru capacitor provides low parallel inductance and offers excellent decoupling capability for all high di/dt environments and provides significant noise reduction in digital circuits to <5 GHz. A large range of capacitor values are available in either NP0 or X7R ceramic dielectrics. L2F Series L3F Series 0805 1206 OUTPUT SIGNAL LINE - INPUT GROUND CAPACITOR VALUES Part Number L2F11A 220 8ATxx L2F11A 470 8ATxx L2F11A 101 8ATxx L2F11A 221 8ATxx L2F11A 471 8ATxx L2F15C 102 8ATxx L2F15C 222 8ATxx L2F15C 472 8ATxx L2F15C 103 8ATxx L2F15C 223 8ATxx L2F15C 473 8ATxx L3F11A 220 8ATxx L3F11A 470 8ATxx L3F11A 101 8ATxx L3F11A 221 8ATxx L3F11A 471 8ATxx L3F15C 102 8ATxx L3F15C 222 8ATxx L3F15C 472 8ATxx L3F15C 103 8ATxx L3F15C 223 8ATxx L3F15C 473 8ATxx Size 0805 0805 0805 0805 0805 0805 0805 0805 0805 0805 0805 1206 1206 1206 1206 1206 1206 1206 1206 1206 1206 1206 Voltage 100V 100V 100V 100V 100V 50V 50V 50V 50V 50V 50V 100V 100V 100V 100V 100V 50V 50V 50V 50V 50V 50V Dielectric NP0 NP0 NP0 NP0 NP0 X7R X7R X7R X7R X7R X7R NP0 NP0 NP0 NP0 NP0 X7R X7R X7R X7R X7R X7R Capacitance 22pF 47pF 100pF 220pF 470pF 1000pF 2200pF 4700pF 10000pF 22000pF 47000pF 22pF 47pF 100pF 220pF 470pF 1000pF 2200pF 4700pF 10000pF 22000pF 47000pF PERFORMANCE CHARACTERISTICS NP0 X7R +50%, -20% +50%, -20% 100V 50V 300mA 300mA 1000MΩ 1000MΩ <0.6Ω <0.6Ω -55 to +125°C Capacitance Tolerance Voltage Rating Current Rating Insulation Resistance DC Resistance Operating Temperature Range Not RoHS Compliant HOW TO ORDER L Style 3 F Size Feedthru 2 = 0805 3 = 1206 1 5 C 8 A Number Voltage* Dielectric Capacitance Capacitance Failure Rate of Code Tolerance A = Not Applicable 1 = 100V A = NP0 Elements 5 = 50V C = X7R 8 = +50/-20% *Note: NP0 available in 100V only and X7R available in 50V only. REV 01 223 B 3 A Termination Packaging Code (Reel Size) Quantity Code (Pcs./Reel) B = Plated SnPb 1 & 2 = 7" Reel Embossed Tape 3 & 4 = 13" Reel Embossed Tape F = 1,000 A = 2,000, 4,000 or 10,000 5 Feedthru 0805/1206 Tin/Lead Capacitors L2F/L3F Series Common Ground Feedthru Pad L S Feedthru Pad CL X BL T W EW BW Common Ground DIMENSIONS 0805 MM (in.) 1206 MM (in.) L 2.01 ± 0.20 (0.079 ± 0.008) 3.20 ± 0.20 (0.126 ± 0.008) W 1.25 ± 0.20 (0.049 ± 0.008) 1.60 ± 0.20 (0.063 ± 0.008) T 1.14 Max. (0.045 Max.) 1.27 Max. (0.050 Max.) BW BL 0.46 ± 0.10 0.18 + 0.25 -0.08 (0.018 ±0.004) (0.007 + 0.010 -0.003) 0.89 ± 0.10 0.18 + 0.25 -0.08 (0.035 ± 0.004) (0.007 + 0.010 -0.003) EW 0.25 ± 0.13 (0.010 ± 0.005) 0.38 ± 0.18 (0.015 ± 0.007) X 1.02 ± 0.10 (0.040 ± 0.004) 1.60 ± 0.10 (0.063 ± 0.004) S 0.23 ± 0.15 (0.009 ± 0.006) 0.46 ± 0.15 (0.018 ± 0.006) T P P S C W L RECOMMENDED SOLDER PAD LAYOUT (TYPICAL DIMENSIONS) 0805 MM (in.) 1206 MM (in.) T 3.45 (0.136) 4.54 (0.179) P 0.51 (0.020) 0.94 (0.037) S 0.76 (0.030) 1.02 (0.040) W 1.27 (0.050) 1.65 (0.065) L 1.02 (0.040) 1.09 (0.043) C 0.46 (0.018) 0.71 (0.028) TYPICAL FEEDTHRU CHIP CAP CONNECTION Physical Layout - A Feedthru Chip Component Model Ground Vcc or Signal Out Vcc or Signal In Signal Out Signal In Ground Ground The terminals are connected internally side to side. Left side and right side are connected and front and back are connected internally. For Decoupling, the chip is usually surrounded by four vias, two for Vcc and two for GND. For Signal Filtering, the in and out lines need to be separated on the circuit board. Physical Layout - B Ground Vcc Vcc Ground 6 REV 01 High Current Feedthru Capacitors W2H Series GENERAL DESCRIPTION MECHANICAL CHARACTERISTICS High current feedthru capacitors are designed as a broadband EMI filter that is specially designed to have high current handling capability. These SMT feedthru filters offer an optimized frequency response with high attenuation across a wide RF spectrum due to optimized parallel and series inductances. These W2H feedthru filters can actually replace discrete L/C filter networks. • Available in EIA 0805 • Plated Tin over Nickel Barrier • Packaged in Tape & Reel TYPICAL APPLICATIONS • • • • • FEATURES • Low parallel inductance provides significant noise reduction in circuits with operating frequencies up to 5GHz • Broad frequency response with high attenuation • High rated current – up to 2A for 080 • Small size – 0805 • Reeling in accordance with EIA-481 High current power (Vcc) lines PA decoupling DC:DC converters Regulators Power supervisory circuits HOW TO ORDER W2H1 5 C 473 Size & Style W2H1 = 0805 W = Plated Ni & Sb L = Plated SnPb Voltage 3 = 25v 5 = 50v 1 = 100v Dielectric A = NP0 C = X7R Capacitance Code 8 A T Failure Capacitance Terminations Rate Tolerance T = Plated Ni & Sn 8 = +50/-20% A = Not B = Plated SnPb Applicable M = ±20% 3 A Packaging Code (Reel Size) 1 & 2 = 7" Reel Embossed Tape 3 & 4 = 13" Reel Embossed Tape Quantity Code (Pcs./Reel) F = 1,000 A = 2,000, 4,000 or 10,000 LEAD-FREE COMPATIBLE COMPONENT PINOUT CONFIGURATION Ground Signal/Vcc Signal/Vcc Ground W2H1 – 0805 Style REV 01 7 High Current Feedthru Capacitors W2H ELECTRICAL PARAMETERS Insulation Resistance DC Resistance Operating Temperature 1000 MΩ Minimum <0.150 Ω -55C to +125C CAPACITOR VALUES Part Number W2H13C 104 8AT W2H15C 473 8AT W2H15C 223 8AT W2H15C 103 8AT W2H15C 102 8AT W2H11A 471 8AT W2H11A 221 8AT W2H11A 101 8AT W2H11A 470 8AT W2H11A 220 8AT Size 0805 0805 0805 0805 0805 0805 0805 0805 0805 0805 Dielectric X7R X7R X7R X7R X7R NP0 NP0 NP0 NP0 NP0 Capacitance 100,000pF 47,000pF 22,000pF 10,000pF 1,000pF 470pF 220pF 100pF 47pF 22pF Tolerance +50%, -20% +50%, -20% +50%, -20% +50%, -20% +50%, -20% +50%, -20% +50%, -20% +50%, -20% +50%, -20% +50%, -20% Voltage 25V 50V 50V 50V 50V 100V 100V 100V 100V 100V Current 2A 2A 1A 1A 1A 0.5A 0.5A 0.5A 0.5A 0.5A PHYSICAL DIMENSIONS AND PAD LAYOUT L T BW C P X T W S S BL EW W L P W2H1 – 0805 Style PHYSICAL DIMENSIONS L W W2H1– 0805 MM 2.01 ± 0.20 1.25 ± 0.20 (in.) (0.079 ± 0.008) (0.049 ± 0.008) T 1.14 Max. (0.045 Max.) BW 0.46 ± 0.10 (0.018 ±0.004) BL 0.18 + 0.25 -0.08 (0.007 + 0.010 -0.003) ES NA EW 0.25 ± 0.13 (0.010 ± 0.005) X 1.02 ± 0.10 (0.040 ± 0.004) S 0.23 ± 0.05 (0.009 ± 0.002) PAD DIMENSIONS W2H1– 0805 MM (in.) 8 T 3.45 (0.136) P 0.51 (0.020) S 0.76 (0.030) W 1.27 (0.050) L 1.02 (0.040) C 0.46 (0.018) X NA REV 01 Feedthru 0805/1206 Capacitors W2F/W3F Series Applications APPLICATIONS FEATURES MARKET SEGMENTS EMI Suppression Broadband I/O Filtering Vcc Line Conditioning Standard EIA Sizes Broad Frequency Response Low ESR 8 mm Tape and Reel Computers Automotive Power Supplies Multimedia Add-On Cards Bar Code Scanners and Remote Terminals PCMCIA Cards Medical Instrumentation Test Equipment Transceivers/Cell Phones Typical Circuits Requiring EMI Filtering THE FOLLOWING APPLICATIONS AND SCHEMATIC DIAGRAMS SHOW WHERE FEEDTHRU CAPACITORS MIGHT BE USED FOR EMI SUPPRESSION • • • • • Digital to RF Interface Filtering Voltage Conditioning in RF Amplifiers Power Decoupling GaAs FET Transistor Preamplifier Vcc Line Filtering on Frequency Control Circuit Clock, Data, Control Line High Frequency Decoupling (Frequency Synthesizer) (SEE APPLICATION NOTES) DIGITAL TO RF INTERFACE FILTERING Audio Digital Block RF Block = Feedthru REV 01 9 Feedthru 0805/1206 Capacitors W2F/W3F Series VOLTAGE CONDITIONING IN RF AMPLIFIERS +28V Q1 R1 D1 C9 RFC1 R4 R6 +28V RFC7 Q2 C25 C18 RFC2 R2 Z1 RF in C1 RFC5 Z2 C2 Z6 Z5 C3 C4 C11 C12 T2 C13 Q3 T1 C14 C10 C5 C21 RFC4 RFC3 Filter Q4 Z3 L1 Z7 Z4 C22 Z8 L2 R3 C6 C7 C8 C16 C15 RFC6 C23 RFC8 +28V L3 R5 = Feedthru C26 C20 C24 RF Out POWER DECOUPLING GaAs FET TRANSISTOR PREAMPLIFIER C2 S.M. = SILVER MICA J1 INPUT 1.5pF TYPICAL L3 Q1 L4 R2 L2 500 R1 POT U1 78L05 IN OUT GND C6 0.1 = Feedthru L6 C8 62 1/4W 200 CHIP C4 51 1/8W R3 15 S.M. S C1 L1 200 C5 CHIP D G 200 CHIP RFC1 FB 5.6 S.M. J2 OUTPUT C3 L5 1N914 +12/14V 14mA D2 D1 C7 0.1 16V 0.4W 1000 F.T. Vcc LINE FILTERING ON FREQUENCY CONTROL CIRCUIT 6-6.35 MHz VFO C87 0.022 C85 C80 82 C81 24pF C82 82 2 L3 C83 24 C84 50 2N5486 Q25 D25 1N914 R136 1M U10 78L05 R141 100 C91 Reg 0.022 IN OUT GND 2.2μF C90 R138 16V + 100k R137 47k C86 10 R139 100k = Feedthru 10 C89 0.022 FB1 Q26 VCC To Bilateral Mixer T14 40673 R140 100 C88 0.022 REV 01 High Current Feedthru Capacitors W2H Series APPLICATIONS PA Filtering Dual Power Switch Filtering W2H15C1048AT1A 3.3V PCMCIA Card 5VIN 5V I/O Bus Controller REV 01 W2H15C1038AT1A 3VIN VC120630D650 TransGuard RF OUT 11 Feedthru 0805/1206 Capacitors W2F/W3F Series EMI REDUCTION THROUGH THE USE OF SMT FEEDTHRU CAPACITORS ABSTRACT Today’s high speed, miniaturized semiconductors have made EMI issues a key design consideration. This paper briefly defines EMI and illustrates the capability of SMT feedthru capacitors. WHAT IS EMI? The term EMI stands for Electromagnetic Interference and refers to signals/energy interfering with a circuit or systems functions. In an electronic system, two classes of energy are generated - wanted and unwanted. Both are potential sources of EMI(1). Wanted signals such as clocks and bus lines could cause EMI if they were not decoupled, terminated or filtered properly. Unwanted signals (cell phones, police radios, power supply noise, etc.) could be conducted or radiated into the circuit due to poor circuit layout, improper decoupling or a lack of high frequency filtering. In either type of EMI signal interference, the system could be rendered useless or put into a state which would cause early failure of its semiconductors. Even worse, the unwanted energy could cause an incorrect answer to be generated from a computer by randomly powering a gate up or down. From all of this we can gather that EMI is a complex problem, usually with no one solution. EMI interference can be a random single shot noise (like a SCR firing) or repetitive in nature (stepper motor or relay noise). The interference can enter into our designs either by being induced by E/B fields, or it can be conducted through control lines or a communication bus. EMI can even be self generated by internal components that generate steep risetime waveforms of voltage or current. ty and can be processed in the same end user production methods as standard capacitors. What feedthru capacitors offer is an optimized frequency response across a wide RF spectrum due to a modified internal electrode design. An application comparison between an SMT feedthru and a discrete capacitor is shown in Figure 1. Signal Trace Signal Trace Signal Trace Signal Trace INPUT OUTPUT INPUT OUTPUT FEEDTHRU FILTER SMT CAPACITOR Figure 1. Comparison of Feedthru Capacitors to Discrete Capacitors The key difference between the two filtering methods is that the feedthru has a much lower inductance between the signal line and ground than the capacitor. The difference in inductances can be in the range of roughly one order magnitude with a feedthru capacitor. This inductance can be shown in an electrical sense through the model for a feedthru and a capacitor (Figure 2). INPUT OUTPUT FEEDTHRU FILTER INPUT OUTPUT SMT CAPACITOR HOW CAN EMI BE CONTROLLED? EMI is most efficiently controlled by realizing it to be a design parameter in the earliest stages of the design. This way, the board layout can be optimized with large power and ground planes which will be low impedance in nature. The use of SMT feedthru filters will yield optimal results. SMT FEEDTHRU CAPACITORS AVX introduced feedthru capacitors to supply a broadband EMI filter capacitor for source suppression and receiver noise reduction. SMT feedthru capacitors use the same material systems as standard ceramic capacitors. They exhibit the same reliabili- Figure 2. Comparison of Feedthru Capacitors to Discrete Capacitors The feedthru capacitor has a minimized parallel inductance and an optimal series inductance (which broadens the frequency response curve). Typical attenuation graphs are shown in Figure 3A. These curves demonstrate feedthru capacitors advantage of a broad frequency response with high attenuation. They also serve as a comparison to the inductance of even lower inductance devices (primarily used in extreme decoupling cases and switch mode power supplies) - see Figure 3B. (1)Practical Design for Electromagnetic Compatibility edited by Rocco F. Ficchi Hayden Book Company 1978 12 REV 01 Feedthru 0805/1206 Capacitors W2F/W3F Series SMT FEEDTHRU CAPACITOR TERMINOLOGY W3F15C2228AT High Frequency Analysis 0 -3dB ~ 2.30 MHz S21 (dB) -10 -20 -30 -40 -50 -60 1.E+05 1.E+06 1.E+07 1.E+08 1.E+09 AVX’s feedthru capacitors have additional technical terminologies relative to standard ceramic capacitors. The reason for this is due to the series manner in which the feedthru element is connected to the circuit. The most important term is DC Resistance. The DC resistance of the feedthru is specified since it causes a minor signal attenuation which designers can calculate by knowing the maximum resistance of the part. The maximum current capability of the part is also of interest to designers since the feedthru may be placed in series with the voltage line. Frequency (Hz) APPLICATION AND SELECTION OF SMT FEEDTHRU CAPACITOR FILTERS Figure 3A. Typical Attenuation Graph 30 Impedance 10 IDC 3 Feedthru 1 0612 0.3 1206 0.1 0.03 0.01 0.1 1 10 100 Frequency, MHz Figure 3B. Comparison of SMT Capacitor Frequency Response to Feedthru Filters 1000 EMI suppression and receiver noise reduction can be achieved most effectively with efficient filtering methods. Attenuations of over 100 dB are achievable depending on the complexity and size of the filters involved. However, before filtering is discussed, another EMI reduction method is noise limiting, using a series element (inductors or resistors). This method is easy to implement and inexpensive. The problem it poses is that it can only reduce noise by -3 to -10 dB. Because of that, series element EMI reduction is primarily used where there is a poor ground. SMT feedthru filter capacitors can actually replace discrete L/C filter networks (depending on the frequency response needed). The SMT filter capacitors should first be chosen for its specific frequency response. Then the voltage rating, DCR, and current capability must be evaluated for circuit suitability. If there is not a match on voltage, current and DC resistance ratings, the designer must select the closest available frequency response available on parts that will meet the design’s power spec. The top 5 applications for SMT feedthru filter capacitors are: 1. 2. 3. 4. 5. REV 01 Digital to RF interface filtering. Control line high frequency decoupling. Data and clock high frequency decoupling. Power line high frequency decoupling. High gain and RF amplifier filtering. 13 AMERICAS EUROPE ASIA-PACIFIC ASIA-KED (KYOCERA Electronic Devices) AVX Greenville, SC AVX Limited, England Tel: 864-967-2150 Tel: +44-1276-697000 AVX/Kyocera (S) Pte Ltd., Singapore KED Hong Kong Ltd. Tel: +852-2305-1080/1223 Tel: +65-6286-7555 AVX S.A.S., France Tel: +33-1-69-18-46-00 AVX/Kyocera, Asia, Ltd., Hong Kong AVX GmbH, Germany Tel: +852-2363-3303 Tel: +49-0811-95949-0 AVX SRL, Italy AVX/Kyocera Yuhan Hoesa, South Korea Tel: +39-02-614-571 Tel: +82-2785-6504 AVX Czech Republic AVX/Kyocera HK Ltd., Taiwan Tel: +420-57-57-57-521 KED Hong Kong Ltd. Shenzen Tel: +86-755-3398-9600 KED Company Ltd. Shanghai Tel: +86-21-3255-1833 KED Hong Kong Ltd. Beijing Tel: +86-10-5869-4655 Tel: +886-2-2656-0258 AVX/ELCO UK KED Taiwan Ltd. Tel: +44-1638-675000 AVX/Kyocera (M) Sdn Bhd, Malaysia ELCO Europe GmbH Tel: +60-4228-1190 Tel: +49-2741-299-0 AVX S.A., Spain AVX/Kyocera International Trading Co. Ltd., Shanghai Tel: +34-91-63-97-197 Tel: +86-21-3255 1933 AVX Benelux AVX/Kyocera Asia Ltd., Shenzen Tel: +65-6509-0328 Tel: +86-755-3336-0615 Kyocera Corporation Japan AVX/Kyocera International Trading Co. Ltd., Beijing Tel: +81-75-604-3449 Tel: +31-187-489-337 Tel: +886-2-2950-0268 KED Korea Yuhan Hoesa, South Korea Tel: +82-2-783-3604/6126 KED (S) Pte Ltd. Singapore Tel: +86-10-6588-3528 AVX/Kyocera India Liaison Office Tel: +91-80-6450-0715 Contact: A KYOCERA GROUP COMPANY http://www.avx.com S-FTCA0M815-C