Barry Breen, Chaim Goldberger Leonid Talalaevsky Israel P.O.B. 23383,

The Datasheet Archive - 100 Million Datasheets from 7500 Manufacturers.

Barry Breen, Chaim Goldberger Leonid Talalaevsky Israel P.O.B. 23383,

Datasheet Thumbnail

Top Searches for this datasheet

ACCU-L MULTI-LAYER INDUCTOR HIGH FREQUENCY APPLICATIONS
Barry Breen, Chaim Goldberger Leonid Talalaevsky Israel P.O.B. 23383, Jerusalem 91233, Israel
telecommunications industry today undergoing changes. miniaturization electronic circuits higher frequencies radio communication systems such Cellular Telephones, places demands passive components. High frequency inductors have kept pace with demands. responded these requirements putting market miniature (0805) high frequency inductor based thin film technology. This article presents basic concepts high frequency inductors such value inductors measured characterized. Here, too, there between high frequency designer's need ever tighter tolerance parts ability off-the-shelf test equipment provide high accuracy measurement.
ACCU-L MULTI-LAYER INDUCTOR HIGH FREQUENCY APPLICATIONS
Barry Breen, Chaim Goldberger Leonid Talalaevsky Israel P.O.B. 23383, Jerusalem 91233, Israel
miniaturization electronic circuits higher frequencies radio communication systems such Cellular Telephones, PCN, GPS, etc., created need improved inductor chip high frequency applications. coil, designated ACCU-L, been developed using thin film technology (see Fig. This technology makes possible achieve small true coil chip wound wire) with high high SRF. inductor available size 0805 (2x1.5x0.9mm).
CONDUCTOR LAYER
PASSIVATION FILL
Introduction
telecommunications industry today undergoing changes. major industry trends, particularly cellular telephone, are: equipment designed higher operating frequencies miniature surface mount devices (SMD). Typical sizes passive components 1206 (3.0x1.6mm) 0805 (2.0x1.3mm). operating frequencies cellular telephone presently 450MHz 900MHz, while future frequencies already planned 1700MHz 1900MHz. trends miniaturization utilization higher operating frequencies dictate introduction modifications physical electrical characteristics individual components used circuits. major passive components, adaptation capacitors resistors these demands kept pace with requirements. major component which proven somewhat problematic, however, inductor.
INSULATOR ALUMINA TERMINATION CONDUCTOR LAYER
Fig. Multi-Layer Inductor Chip High Frequency Applications
Typical Inductors Present
type inductor most commonly utilized present high frequency applications wire wound around non-magnetic core (Fig. nonmagnetic core clearly essential high frequency operations since magnetic materials typically exhibit severe property changes above megahertz. copper wire conductor also appropriate this device since high conductivity important high these frequencies. major drawback these inductors their physical construction. There several inherent mechanical problems wire wound design.
Fig. Typical Wire-Wound Inductor Chip Design
device must quite thick (high profile) since lines flux parallel axis (i.e. inductor cross section width thickness) therefore, thin part cannot efficiently designed. Such high profile devices actually skid across board during high speed pick-and-place assembly. terminations part only partial. Furthermore, wire conductor delicate, particularly point contact with termination, leading reliability concerns.
Inductor Guide
Glossary Important Inductor Parameters High Frequency Applications
Inductance. High inductance values factor most high frequency applications. 1.8nH 39nH typically range interest. critical factors stability tolerance inductance operating frequency. Note that accurate measurement these values trivial. Even frequencies (~10MHz), instruments available today exhibit measurement accuracy better than about inductance 10nH. typical application frequencies (450MHz), measurement accuracy even further degraded parasitic capacitance inadequately characterized test fixtures. Parasitic Capacitance. inductors include certain capacitance characteristic. This capacitance derived from mutual proximity coil windings. capacitance further magnified inductor structural materials, especially these high dielectric constant. critical high frequency inductors that parasitic capacitance minimized since determines device SRF. SRF. Self resonant frequency inductor that frequency which parallel resonance achieved between device inductance parasitic capacitance. Inductor drops zero SRF. quite important, therefore, that inductor much higher than application frequency. Resistance. addition inductance parasitic capacitance, inductor also exhibits resistance. frequencies, resistance conductor track determining factor inductor very high frequencies, resistivity conductor material more important than resistance.
Design Inductors
alternative approach which provides high frequency inductor that both small rugged construct device from layers substrate. This approach, common method forming inductors hybrids which also utilized various wire bondable inductor chips, been incorporated into true device. Figure depicts structure ACCU-L inductor. Multiple inductor layers constructed nonmagnetic substrate alumina. Each layer consists conductor spiral which coated with insulating layer. insulator includes connect overlaying spiral. uppermost layer seals device. total thickness these layers typically less than 0.3mm device thickness (substrate plus inductor layers) only 0.9mm. manufacturing method used building this inductor photolithography. This technique, which been extensively developed microelectronics industry, allows simultaneous formation thousands devices single substrate. individual devices then separated from each other upon completion layers. Bare inductor chips would, course, incompatible with surface mount assembly techniques. Figure shows that this inductor includes full termination with lands. These terminations formed solder coated nickel plate. this termination which converts inductor chip into true inductor.
(resistance resistivity
conductor length cross section
Summary
ACCU-L inductor meets both present future needs high frequency applications. small, rugged, includes full terminations exhibits excellent electrical performance. multilayer construction provides high level control electrical physical characteristics inductor, giving consistent characteristics within lot-to-lot basis. ACCU-L inductor fills void created inability earlier technologies satisfy continuing miniaturization manufacturability requirements high frequency circuits.
This skin effect whereby high frequency current flow largely restricted surface layer conductor. high high frequency, therefore important that coil conductor constructed metal with resistivity.
Inductor Equivalent Circuit
thermal conductivity allowable operating temperature determine capacity device remove heat generated. Power handling relevant parameter high frequency circuits. must considered only when circuit also includes high currents. Dimensions. Circuit board space considerations today demand small, thin parts. High profile parts result assembly problems. Terminations. Full terminations with lands preferred termination geometry. material should solder coated nickel plate. This type termination provides optimum solderability, strength leach resistance inductor. Environmental Reliability. Inductors must built withstand number environmental stresses incurred during circuit assembly subsequent field operation. These include exposure variety chemicals, humidity, temperature, mechanical stress thermal cycling. Most stresses occur while current voltage bias exist device. inductor construction must such that part will fail result these environmental stresses.
Intrinsic inductance Resistance including skin effect Parasitic Capacitance Effective inductance Quality Factor. This most important measure inductor performance after inductance stability. factor ratio reactive impedance equivalent series resistance (ESR, below). measure degree which device lossy. High means dissipation means high dissipation. Where: Rs/(1-2LC)2 frequency resistance including skin effect (for thick conductors: t>5) where conductor thickness. resistance skin depth Leff
Measuring Inductors High Frequencies
value inductors, particularly below 20nH, present very difficult measurement challenge. Measurement accuracy better than straight-forward components such capacitors resistors, including values. inductors, even best offthe-shelf equipment cannot provide measurement accuracy better than 10nH parts. Until recently, limitation measurement accuracy value parts significant. Suppliers offered inductors with tolerances ±10% ±20% this adequate circuit designers' requirements. rapidly expanding high frequency telecommunications industry dramatically changed this situation. Poor tolerance inductors lead added cost mass produced cellular sets similar high frequency devices. Conversely, tight tolerance inductors actually allow redesign reduce parts count and, therefore, reduce manufacturing cost. ACCU-L designed tight tolerance inductance. variance ACCU-L, however, cannot characterized available instruments fixturing poor accuracy these instruments. Since sufficiently accurate instruments available, measurement techniques were developed accurately test ACCU-L electrical parameters. This section presents these methods used measure major electrical parameters ACCU-L inductance, Q-factor self-resonant frequency (SRF).
conductor resistivity (-cm) permeability, 10-9 H/cm Reactive Impedance
Effective Inductance. Even non-magnetic inductors will exhibit increased measured inductance with frequency when measurement performed impedance analyzer. This effective impedance from device parasitic capacitance. Leffective measured
Power Handling. inductors, this basically maximum current that device carry without overheating. Power handling capability depends primarily three traits inductor: ESR, thermal conductivity inductor materials maximum allowable operating temperature. determines amount power dissipated inductor. Material
Measurement Self Resonant Frequency (SRF).
most accurate straight forward measurement self resonant frequency value inductors obtained with vector analyzer (eg. Wiltron Model Vector Network Analyzer). Since these inductors have very high (eg. 14GHz ACCU-L 2.7nH), vector analyzer with frequency capability 20GHz more necessary. appropriate fixture stripline design shown Figure that frequency which forward transmission, S21, minimum (Fig. 1-2LCP
FORWARD TRANSMISSION
MAG.
REF=20.000dB
20.000dB/DIV
REF. PLANE 0.0000 MARKER 3.2320 -38.513 -8.98
MARKER MARKER
0.0400
4.0000
PHASE
REF=-10.00°
60.00°/DIV
When
Fig.
therefore,
STRIP LINE S.R.F. MEASUREMENT 10.0
Measurement Inductance. inductor parameters, inductance factor which high accuracy measurement most significance. Optimal performance high frequency circuits will generally more sensitive inductance variance than variance other inductor characteristics. discussed above, standard measurement instruments will provide required accuracy. using vector analyzer with stripline fixture design presented Figure measurement accuracy ±0.1nH obtained measurement frequency 450MHz. This means measurement accuracy 10nH device ±3.7% 2.7nH device. second generation fixture presently under development will further improve measurement accuracy this technique ±0.05nH.
STRIP LINE INDUCTANCE MEASUREMENT
0.64
10.0
0.64
0.64
dimensions
Fig.
4.86
0.64
K=9.6
dimensions
Fig.
This fixture designed port device where S-parameter sufficient calculate inductance. Note that intention effective inductance: Leff
Intrinsic inductance, could also calculated after determining parasitic capacitance, This generally required since circuit designer needs, fact, impedance value alternatively proportional term, Leff.
Measurement Quality Factor,
Q-factor measured with good accuracy using Boonton Model Resonant Transmission Line described addendum Model manual. model precisely characterized coax line which formally supported industry standards RS-48 752-82 measuring capacitors. When used described addendum, Model measures Q-factor inductors with accuracy ±(3+Q0.35)%. typical inductor this means accuracy ±7%. Note that Model also measure inductance values range 20nH 1000nH with accuracy ±3%. However, accuracy inductance measurement degrades significantly inductance below 20nH. Inductor factor also accurately measured using vector analyzer with appropriate fixture. Such fixture presently under development.
Application Wireless Cellular Communications Radar Detector Cable Vehicle Location Systems Paging Military Communications Test Measurement Filters Amplifiers VCO's Matching Networks
Frequency 450MHz 900MHz 900MHz 1.7GHz 2.3GHz 800MHz 900MHz 1.5GHz 1.6GHz 10GHz 10GHz
Matching Network
ACCU-F ACCU-L ACCU-F ACCU-L ACCU-F ACCU-L ACCU-F
Front Filter
ACCU-L
Applications
ACCU-L characteristics give circuit designer possibilities design circuits higher frequency applications, tighter performance requirements, lower costs ease mass production. ACCU-L inductor meets both present future needs high frequency applications. small, rugged, includes full terminations exhibits excellent electrical performance. ACCU-L minimizes necessity tuning elements reduces drastically "tweaking" final product important factor high volume production. easy availability tight inductance tolerances makes ACCU-L ideal choice design filters matching networks (see diagrams common applications). following some major applications ACCU-L.
ACCU-F
Harmonic Suppressor
Osc.
ACCU-F ACCU-L ACCU-F
ACCU-L
Harmonic Filter
ACCU-L
filter
ACCU-L
NOTICE: Specifications subject change without notice. Contact your nearest Sales Office latest specifications. statements, information data given herein believed accurate reliable, presented without guarantee, warranty, responsibility kind, expressed implied. Statements suggestions concerning possible products made without representation warranty that such free patent infringement recommendations infringe patent. user should assume that safety measures indicated that other measures required. Specifications typical apply applications.
Myrtle Beach, Tel: 803-448-9411 FAX: 803-448-1943 Vancouver, Tel: 206-696-2840 FAX: 206-695-5836 Olean, Tel: 716-372-6611 FAX: 716-372-6316 Raleigh, Tel: 919-878-6200 FAX: 919-878-6462 Biddeford, Tel: 207-282-5111 FAX: 207-283-1941 Limited, Fleet, Hants, England Tel: (01252) 770000 FAX: (01252) 770001 S.A., France Tel: 6918 4600 FAX: 6928 7387 AVXGmbH, Germany Tel: 08131 9004-0 FAX: 08131 9004-44 s.r.l., Milano, Italy Tel: 02-665 00116 FAX: 02-614 2576 AVX/Kyocera (HK) Ltd. Tel: 852-363-3303 FAX: 852-765-8185 AVX/Kyocera (Singapore) Pte. Ltd. Tel: (65) 258-2833 FAX: (65) 258-8221 Israel Ltd. Tel: 972-957-3873 FAX: 972-957-3853 AVX/Kyocera Corp. Tel: 75-593-4518 FAX: 75-501-4936
S-ALMI2.5M894-R

Barry Breen, Chaim Goldberger Leonid Talalaevsky Israel P.O.B. 23383,

Top Searches for this datasheet

Other recent searches