Dispositivos Semiconductores Copyright Pedro Julin Dispositivos Semiconductores DIECUNS

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Dispositivos Semiconductores Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Dispositivos Semiconductores Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Capacitores Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Capacitores Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Modelo ideal Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Modelo ideal Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Electrical Parameters (V) n Rated Voltage (UR) q n Operating Voltage (UOP) q n

Electrical Parameters (V) n Rated Voltage (UR) q n Operating Voltage (UOP) q n n Range (between 0 V and Ur) typ. 60% Surge Voltage (US) q n Direct voltage for which the C has been designed For short periods of time Superimposed AC, ripple voltage Reverse voltage Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Electrical Parameters (C) n AC/DC capacitance q n Rated capacitance q n AC value

Electrical Parameters (C) n AC/DC capacitance q n Rated capacitance q n AC value is measured at 20 o. C / 100 Hz-120 Hz Nominal value Tolerance q Described by a code Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Electrical Parameters (C) n n n Temperature dependence Frequency dependence Charge-discharge proof q Frequent

Electrical Parameters (C) n n n Temperature dependence Frequency dependence Charge-discharge proof q Frequent charging/discharging cycles may lead to capacitance variation Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Electrical Parameters (tan δ) n Dissipation factor tan δ Copyright Pedro Julián. Dispositivos Semiconductores

Electrical Parameters (tan δ) n Dissipation factor tan δ Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Electrical Parameters (tan δ) n n n Tan δ variation with temperature and frequency

Electrical Parameters (tan δ) n n n Tan δ variation with temperature and frequency As freq. increases the capacitive impedance reduces and the dissipation factor gets worse Increasing the temperature results in better dissipation factor Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Electrical parameters (Z) n n n R = dielectric losses, series resistance L =

Electrical parameters (Z) n n n R = dielectric losses, series resistance L = winding and terminals (only depends on f ) C and R depend on temp. and f Fig. Temperature behaviour is for an Al electrolytic capacitor Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Electrical Parameters (I) n Leakage current: depends on time, temperature and applied voltage Copyright

Electrical Parameters (I) n Leakage current: depends on time, temperature and applied voltage Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Electrical Parameters (I) n n n Ripple current: rms value of circulating current Depends

Electrical Parameters (I) n n n Ripple current: rms value of circulating current Depends on temp. and frequency Useful life: life achieve without exceeding a specified failure rate. Depends on: q q q Temperature Ripple current Voltage Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Electrical Parameters (I) n Useful life: q Calculation Copyright Pedro Julián. Dispositivos Semiconductores -

Electrical Parameters (I) n Useful life: q Calculation Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Climatic conditions n UCT: Upper category temperature LCT: Lower category temperature Limits within cap.

Climatic conditions n UCT: Upper category temperature LCT: Lower category temperature Limits within cap. Can be continuously operated Storage temperature n There also restrictions on mechanical stress n n n Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Capacitor Types n Electrolíticos q q n Cerámicos q q n G 1 G

Capacitor Types n Electrolíticos q q n Cerámicos q q n G 1 G 2 Film q q q n Al Ta Polietileno (polyester) Polipropileno Metalizados Mica Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Capacitor Types: Values n Electrolíticos q q n q q G 1 G 2

Capacitor Types: Values n Electrolíticos q q n q q G 1 G 2 0. 47µF-10. 000µF / 5 V-500 V 220 n. F-100µF / 1 V – 50 V q 0. 5 p. F – 560 p. F / 63 V – 500 V 100 p. F – 470 n. F / 53 V – 500 V q 1 n. F - 1µF / 100 V – 1000 V q 10 n. F - 10µF / 63 V – 1000 V q 2 p. F – 22 n. F / 250 V – 4000 V q Film q q q n q Cerámicos q n Al Ta Polietileno (polyester) Polipropileno Metalizados Mica Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Capacitor Types: Tolerances n Electrolíticos q q n q q G 1 G 2

Capacitor Types: Tolerances n Electrolíticos q q n q q G 1 G 2 q q Polietileno (polyester) Polipropileno Metalizados Mica -10% / +100 % +- 20% q 2%, 5%, 10% q 0. 5% - 20% q Film q n q Cerámicos q n Al Ta Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

AL Electrolytic Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

AL Electrolytic Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Electrolytic (Al) Capacitors n n Polar elements. Only block current in one direction Anode

Electrolytic (Al) Capacitors n n Polar elements. Only block current in one direction Anode is Al of great purity. Cathode is electrolyte (liquid) and paper Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Electrolytic (Al) Capacitors n n n Anode is etched to provide more surface Dielectric

Electrolytic (Al) Capacitors n n n Anode is etched to provide more surface Dielectric is obtained by oxidation of Al (<1 um thickness) Big values of capacitance Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

V-I curve n n After the forming voltage (Uf) current increases Safe operation is

V-I curve n n After the forming voltage (Uf) current increases Safe operation is ensured below Ur Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Temperature effects n With decreasing temperature, the viscosity of the electrolyte increases, thus reducing

Temperature effects n With decreasing temperature, the viscosity of the electrolyte increases, thus reducing its conductivity. Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Datasheet Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Datasheet Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Tantalium-Niobium Caps. Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Tantalium-Niobium Caps. Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Electrolytic (Ta-Nb) Capacitors n n εr is 27 for Ta, 41 for Nb Polar

Electrolytic (Ta-Nb) Capacitors n n εr is 27 for Ta, 41 for Nb Polar elements. Only block current in one direction Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Frequency dependence Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Frequency dependence Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Z and ESR Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Z and ESR Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Low ESR series Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Low ESR series Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Ultra-low ESR Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Ultra-low ESR Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Maximum V, I vs T and I vs. f Copyright Pedro Julián. Dispositivos Semiconductores

Maximum V, I vs T and I vs. f Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Dissipation factor (vs. f, T) Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Dissipation factor (vs. f, T) Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Leakage Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Leakage Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Ceramic Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Ceramic Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Ceramic capacitors n n n they all have the oxide ceramic dielectric in common.

Ceramic capacitors n n n they all have the oxide ceramic dielectric in common. Ceramic generally means that an inorganic polycrystalline body is formed by sintering at high temperatures. By means of special production methods, extremely thin layers of ceramic materials can be obtained. Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Classification n Class 1 capacitors q q q The dielectric (200) primarily consists of

Classification n Class 1 capacitors q q q The dielectric (200) primarily consists of a mixture of metal oxides and titanates. Defined linear temperature coefficient with reversible temperature dependence Capacitance does not vary with voltage. Low losses at frequencies up to the UHF range High insulation resistance Applications: resonant circuits, filters, timing elements Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Classification n Class 2 capacitors q q q The dielectric ( 200 to 10000)

Classification n Class 2 capacitors q q q The dielectric ( 200 to 10000) primarily consists of titanates (barium, calcium, strontium) and zirconates. Non-linear dependence of capacitance on temperature and voltage Somewhat higher losses and lower insulation resistance than class 1 capacitors Capacitance decreases according to a logarithmic function (ageing). High capacitance values even with small-size capacitors are possible Applications: coupling, blocking, filtering. Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Class 1: Temperature dependence Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Class 1: Temperature dependence Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Class 2: Temperature dependence Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Class 2: Temperature dependence Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Termal characteristics n n Change more (class 2) or less (class 1) with temperature.

Termal characteristics n n Change more (class 2) or less (class 1) with temperature. Change in crystalline structure q q n capacitance value of high K materials (with a high dielectric constant, e. g. X 7 R, Z 5 U) class 2 drastically decreases above the Curie point materials with a low dielectric constant (C 0 G) class 1, dissipation factor increases considerably at high temperatures. high ambient temperature and high electrical energy exchange contributes to heating the capacitor. Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Datasheets (C 0 G) Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Datasheets (C 0 G) Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Datasheets (X 7 R) Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Datasheets (X 7 R) Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Frequency response Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Frequency response Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Film Capacitors Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Film Capacitors Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Classification n n T ˆ= Polyethylene terephthalate (PET) P ˆ = Polypropylene (PP) N

Classification n n T ˆ= Polyethylene terephthalate (PET) P ˆ = Polypropylene (PP) N ˆ= Polyethylene naphthalate (PEN) An M (ˆ = Metallization) is prefixed to the short identification code of capacitors with metallized films. Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Winding method Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Winding method Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Stacked method n n The “master capacitors” are produced under well-defined and constant conditions.

Stacked method n n The “master capacitors” are produced under well-defined and constant conditions. Since each individual layer acts as a separate capacitor element, any damage to the contacts due to overloading is restricted to the respective capacitor element and does not affect the entire capacitor Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Film vs. Foil Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Film vs. Foil Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Self-healing property n Capacitors with metallized plastic film have a decisive advantage over capacitors

Self-healing property n Capacitors with metallized plastic film have a decisive advantage over capacitors with metal foil electrodes: they have self-healing properties. q q q Self-healing properties permit utilization of full dielectric strength of dielectric materials of metallized film capacitors metal-foil electrode capacitors must always be designed with a safety margin to allow for any possible faults in the dielectric. Metallized types thus have a distinct size advantage, which is particularly apparent with the larger capacitance ratings. Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Self-healing property Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Self-healing property Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Temperature n n Polypropylene capacitors have negative temperature coefficient Polyester capacitors have positive temperature

Temperature n n Polypropylene capacitors have negative temperature coefficient Polyester capacitors have positive temperature coefficient Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Humidity n the dielectric and the effective air gap between the films will react

Humidity n the dielectric and the effective air gap between the films will react to changes in the ambient humidity Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Frequency n MKT , MFT and MKN MKP and MFP capacitors: Up to a

Frequency n MKT , MFT and MKN MKP and MFP capacitors: Up to a frequency of 1 MHz, the capacitance remains virtually unaffected by the frequency. Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Maximum voltage (T) Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Maximum voltage (T) Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

V/I limitations n n n A) corona discharge B) Thermal dissipation C) Leads resistance

V/I limitations n n n A) corona discharge B) Thermal dissipation C) Leads resistance Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Tan δ n Polypropelene capacitors Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Tan δ n Polypropelene capacitors Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Tan δ n n The dielectric of MKT capacitors contributes a considerably greater dielectric

Tan δ n n The dielectric of MKT capacitors contributes a considerably greater dielectric component tan δD MKT capacitors display a noticeably higher overall dissipation factor, especially at lower frequencies than MKP and MKN capacitors Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Datasheets Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Datasheets Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Polyester n Metallized Polyester Capacitors (Mylar) q q With tolerance of 10% Temperature range

Polyester n Metallized Polyester Capacitors (Mylar) q q With tolerance of 10% Temperature range -40 o. C to +85 o. C. Non inductive. Dielectric strength of 150% of rated voltage for less than 5 sec Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Polyester n Metallized Polyester Film Capacitors q q q With tolerance of 10%. Operating

Polyester n Metallized Polyester Film Capacitors q q q With tolerance of 10%. Operating temperature -40 o. C to +85 o. C. Non Inductive Design Compact Size Available in rolls of 100 or 1, 000 at special prices. Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Mica n Advantages: dielectric material (mica) is inert. q q q n Does NOT

Mica n Advantages: dielectric material (mica) is inert. q q q n Does NOT change physically or chemically with age Good temperature stability. Very resistant to corona damage Unless properly sealed, susceptible to moisture pick-up (increases the power factor and decrease insulation resistance). Higher cost (scarcity of high grade dielectric material) and manually-intensive assembly. Silver mica capacitors have the above mentioned advantages. In addition, they have much reduced moisture infiltration. Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Summary Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Summary Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Summary n n n n Ceramics: low stability and precision. Electrolytic - Same as

Summary n n n n Ceramics: low stability and precision. Electrolytic - Same as ceramics except they have much smaller physical size for a given value. Usually polarized. Large tolerances Tantalum - Better characteristics than electrolytic but still small for high capacity values. Polarized. Smaller tolerance than electrolytic Poly film – (polyester or polypropylene) --mostly replaced paper capacitors-- Slightly better characteristics than common ceramics. Usually very low leakage currents. Mica/Silver Mica - Temperature stable, low dissipation factor. Usually large physically. Polystyrene, Teflon - Very temperature stable. Polystyrene breaks down, however, at high temps (say >80 C) Glass, Air, Oil – Not Common(HV work, big motors) Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Electrolytic Capacitors n Tantalum q q q q Small size Large values Medium inductance

Electrolytic Capacitors n Tantalum q q q q Small size Large values Medium inductance Quite high leakage Usually polarized Expensive Poor stability Poor accuracy n Aluminum q q q q q Large values High currents High voltages Small size High leakage Usually polarized Poor stability Poor accuracy Inductive Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Mica n n n n Widely used in low and medium power RF equipment

Mica n n n n Widely used in low and medium power RF equipment Low loss at HF Low inductance Very stable Available in 1% values or better Quite large Low values (<10 n. F) Expensive Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Film n Polyester q q q q 0. 3% to 0. 5% Moderate stability

Film n Polyester q q q q 0. 3% to 0. 5% Moderate stability Low cost Wide temperature range Low inductance (stacked film) Large size High inductance n Polypropylene q q q 0. 001% to 0. 02% Inexpensive Wide range of values Large case size High inductance Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Appendix Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Appendix Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008

Surface mount formats capacitors n n n n 1. A-case (Tantalum cap) 2. D-Case

Surface mount formats capacitors n n n n 1. A-case (Tantalum cap) 2. D-Case (Tantalum cap) 3 -4 Electrolytic cap 5. 0805 Ceramic 6. 1206 Ceramic 7. 1210 Ceramic 8. High Q Porcelan RF 9. Variable Trimmer Copyright Pedro Julián. Dispositivos Semiconductores - DIEC/UNS 2008