From owner-qrp-l@Lehigh.EDU Wed Feb 12 01:47:55 1997 Received: from fidoii.CC.Lehigh.EDU (fidoii.CC.Lehigh.EDU [128.180.1.4]) by oucsace.cs.ohiou.edu (8.7.6/8.7.1) with ESMTP id BAA07398 for ; Wed, 12 Feb 1997 01:47:54 -0500 (EST) X-Received-x: from fidoii.CC.Lehigh.EDU (fidoii.CC.Lehigh.EDU [128.180.1.4]) by oucsace.cs.ohiou.edu (8.7.6/8.7.1) with ESMTP id BAA07398 for ; Wed, 12 Feb 1997 01:47:54 -0500 (EST) Received: from Lehigh.EDU ([127.0.0.1]) by fidoii.cc.lehigh.edu with SMTP id <35538-38722>; Wed, 12 Feb 1997 01:45:39 -0500 Received: from nss2.CC.Lehigh.EDU ([128.180.1.26]) by fidoii.cc.lehigh.edu with ESMTP id <35429-30017>; Wed, 12 Feb 1997 01:42:17 -0500 Received: from zia.aoc.nrao.edu (zia.aoc.nrao.edu [146.88.1.4]) by nss2.CC.Lehigh.EDU (8.8.5/8.8.5) with SMTP id BAA41117 for ; Wed, 12 Feb 1997 01:40:42 -0500 Received: (from pharden@localhost) by zia.aoc.nrao.edu (8.6.12/8.6.10) id XAA15353 for qrp-l@lehigh.edu; Tue, 11 Feb 1997 23:40:24 -0700 Message-Id: <199702120640.XAA15353@zia.aoc.nrao.edu> Date: Tue, 11 Feb 1997 23:40:24 -0700 Reply-To: pharden@aoc.nrao.edu Sender: owner-qrp-l@Lehigh.EDU Precedence: bulk From: Paul Harden To: "Low Power Amateur Radio Discussion" Subject: DATA SHEET: Capacitors #1 X-Listprocessor-Version: 8.0 -- ListProcessor(tm) by CREN Status: RO DATA SHEET de NA5N: CAPACITORS (part 1 of 2) ------------------------------------------------------------------------ CONTENTS: Brief description of major capacitor types (non-electrolytic) Capacitor identification and coding schemes Temperature Characteristics ************ CAPACITOR TYPES: (non-electrolytic) ************ DISK CERAMICS consist of two metalic plates whose area and spacing deter- mines the capacitance, separated with a ceramic film dielectric and housed in an epoxy molding. >Advantages: inexpensive, small, high C per unit size >Disadvantages: high capacity changes over the temperature range >Uses: blocking, coupling, bypassing and energy storage applications >Use only NPO (see below) for critical timing or oscillator circuits MONOLYTHIC/MULTILAYER CERAMICS are very similar to disk ceramics in characteristics and usage. The major difference is monolythics are made from MULTIPLE layers of electrodes and dielectric films to yield high C in small packages. For this reason, they are also called MULTILAYER ceramics. The multilayered element is usually thermally fused to yield a chip ... which by itself is packaged as a surface mounted chip capacitor, or surrounded by an epoxy moulding to form a monolythic capacitor. >Advantages: inexpensive, small, high C per unit size >Disadvantages: high capacity changes over the temperature range >Uses: blocking, coupling, bypassing and energy storage applications >Use only NPO (see below) for critical timing or oscillator circuits POLYESTER FILM capacitors use layers of metal and polyester (mylar) dielectric to make a wide range of capacitances in a small package and have become the standard for DC applications. >Advantages: inexpensive, small, high C per unit size >Disadvantages: high capacity changes over the temperature range and high loss factors, limiting their use at high frequencies >Uses: blocking, coupling, bypassing and energy storage applications POLYCARBONATE FILM capacitors are layers of metalized film and poly- carbonate dielectric for an almost ideal capacitor. These caps have become the standard for Mil-spec film dielectrics. >Advantages: high insulation resistance, minimal capacitance change with temperature and low loss (dissipation factor). >Disadvantages: costly (3-5 times a disk ceramic) >Uses: blocking, coupling, bypassing, frequency discrimination (like RC filters), critical timing circuits, precision oscillator circuits, and operation in high temperature environments. POLYPROPYLENE FILM capacitors use layers of metal and polypropylene dielectric for low moisture absorption and high breakdown voltages. >Advantages: Low loss factors and good capacitance stability over the temperature range for high frequency applications, H.V. circuits. >Disadvantages: Polypropylene has a low dielectric, resulting in larger physical sizes for comparable capacitances and working voltages than most other capacitor types. About twice the cost of disk ceramics. METAL vs METALIZED FILMS. Capacitor electrodes have traditionally been made from metal alloys. Metalized films use vacuum sputtering techniques to coat a dielectric film with a metal composition to form high C on very thin pieces of film, making for very small sizes. They also tend to be "self healing" in that a high voltage arc will vaporize the metal deposit but will be contained by the dielectric, such that the damage remains localized. An arc will thus not short the capacitor, a common problem with older metal alloy types. **************** CAPACITOR IDENTIFICATION ****************** Capacitors are identified by: 1. Direct value marking (i.e. "27pF 35V") 2. EIA Identification Coding (i.e., "104M"= .1uF, 20%) 3. Color coding schemes (pretend this is red-yellow-orange!) Since color coding schemes are disappearing except for some foreign made tantalums, and direct marking is fairly obvious, only the EIA coding scheme is described. ******** Typical EIA coded capacitor: * Z5U * ---> Temperature characteristics * 224J * ---> Value and tolerance ******** | | TEMPERATURE CHARACTERISTICS: Min. Temp. Max. Temp. Cap. change over temp. range (degrees C) (degrees C) (+/- percentage) X=-55C 2=+45C 4=65C A=1% B=1.5% C=2.2% Y=-30C 5=+85C 6=+105C D=3.3% E=4.7% F=7.5% Z=+10C 7=+125C P=10% R=15% S=20% T=-33%,+22% U=-56%,+22% V=-82%,+22% THEREFORE, a Z5U has an operating temperature range of +10C to +85C and its capacitance changes from -56%C (at +10C) to +22%C (at 85C). VALUE AND TOLERANCE: Example: "2 2 4 M" --- - --------> Tolerance Codes (+/- %) | | F=1pF or 1% G=2pF or 2% (if C>10pf, then %) | | J=5% K=10% L=15% M=20% N=30% Capacitance Number P=0%, +100% W=-20%, +40% in pF of zeros Y=-20%, +50% Z=-20%, +80% THEREFORE, a 224M = 22 0000pF = .22uF, 20% tolerance QUICK REFERENCE CHART (Decade values) 1R0 = 1pF 103 = .01uF 100 = 10pF 104 = .1uF 101 = 100pF 105 = 1uF 102 =.001uF 106 = 10uF 1010= Some numbers used on 10 meters! AFTER ALL OF THAT ... when ordering capacitors, the THREE most common sold by most mail order vendors are Z5U (Class 1) ........ +10C to +85C, -56%,+22% X7R (Class 2) ........ -55C to +125C, 15% (fairly flat <100C) and NP0 (Class 3 or C0G) ... -55C to +150C, <1.5% (ideally flat) The "N" codes indicate the amount of NEGATIVE capacitance change per degree C. Thus, NP0 = 0 ppm/deg C N150 = -150 ppm/deg C N750 = -750 ppm/deg C ... ETC. -------------------------------------------------------------------------- WARNING: The Surgeon General has determined that chewing on orange tantalum "gum drop" capacitors may be hazardous to your health. GL and have fun, Paul NA5N (pharden@nrao.edu) From owner-qrp-l@Lehigh.EDU Wed Feb 12 01:52:29 1997 Received: from fidoii.CC.Lehigh.EDU (fidoii.CC.Lehigh.EDU [128.180.1.4]) by oucsace.cs.ohiou.edu (8.7.6/8.7.1) with ESMTP id BAA07527 for ; Wed, 12 Feb 1997 01:52:28 -0500 (EST) X-Received-x: from fidoii.CC.Lehigh.EDU (fidoii.CC.Lehigh.EDU [128.180.1.4]) by oucsace.cs.ohiou.edu (8.7.6/8.7.1) with ESMTP id BAA07527 for ; Wed, 12 Feb 1997 01:52:28 -0500 (EST) Received: from Lehigh.EDU ([127.0.0.1]) by fidoii.cc.lehigh.edu with SMTP id <35263-30017>; Wed, 12 Feb 1997 01:50:54 -0500 Received: from nss2.CC.Lehigh.EDU ([128.180.1.26]) by fidoii.cc.lehigh.edu with ESMTP id <35352-32579>; Wed, 12 Feb 1997 01:42:31 -0500 Received: from zia.aoc.nrao.edu (zia.aoc.nrao.edu [146.88.1.4]) by nss2.CC.Lehigh.EDU (8.8.5/8.8.5) with SMTP id BAA86041 for ; Wed, 12 Feb 1997 01:41:09 -0500 Received: (from pharden@localhost) by zia.aoc.nrao.edu (8.6.12/8.6.10) id XAA15370 for qrp-l@lehigh.edu; Tue, 11 Feb 1997 23:41:05 -0700 Message-Id: <199702120641.XAA15370@zia.aoc.nrao.edu> Date: Tue, 11 Feb 1997 23:41:05 -0700 Reply-To: pharden@aoc.nrao.edu Sender: owner-qrp-l@Lehigh.EDU Precedence: bulk From: Paul Harden To: "Low Power Amateur Radio Discussion" Subject: DATA SHEET: Capacitors #2 X-Listprocessor-Version: 8.0 -- ListProcessor(tm) by CREN Status: O DATA SHEET de NA5N: CAPACITORS (part 2 of 2) updated 3-95 ------------------------------------------------------------------ Contents: SELECTION AND ORDERING GUIDE DEFINITION OF TERMS STANDARD VALUES OF CERAMIC/FILM CAPS **************** SELECTION GUIDE ******************* (PRINCIPAL CHARACTERISTICS OF MAJOR CAPACITOR TYPES) To compare characteristics between the major types -------------------------------------------------------------------------- CHARACTERISTIC CERAMICS POLYESTER POLY- POLY- (X7R's) FILM CARBONATE PROPYLENE TANTALUM -------------------------------------------------------------------------- Capacitance range 10p-1uF .001-15uF .001-22uF .001-30uF .01-1000uF Typical tolerance +/-20% +/-20% +/-10% +/-10% +/-5% Voltage range 50-200v 50v-15kv 30-600v 100-800v 6-125v Temperature range -55,+125 -65,+150 -65,+125 -65,+105 -55,+125 Temp. Coefficient +/-15% +/-15% +/-2% +/-2% +/-8% Insulation Resistance for <1uF, Megs/uF 10**4 10**4 10**5 10**7 70M ohms for >1uF, Megs/uF 10**4 10**3 10**5 10**5 10M ohms Dissipation factor at 1KHz 2.5% 1.0% 0.3% 0.1% 8-24% Dielectric Absorption 2.5% 0.5% 0.35% 0.05% na Stability (1000hrs) 10% 10% 5% 3% 10% -------------------------------------------------------------------------- Design Considerations: -Physical size 1 4 5 8 3 small moderate large largest moderate -Cost factor 1 1 3-5 2-3 3 low low high moderate moderate -Stability moderate moderate excellent excellent moderate -Temp. stability poor poor excellent excellent moderate -Freq. usage DC-low DC-low HF-VHF HF-VHF DC-low -------------------------------------------------------------------------- REFERENCES: Mallory Electronic Components Catalog Sprague Film Capacitor Catalog Sprague Capacitor Designers Guide for Engineers MuRata/Erie Ceramic Capacitor Catalog DEFINITIONS: *CAPACITANCE TOLERANCE is the maximum deviation between the nominal value (as marked on the capacitor) and the actual capacitance. *WORKING VOLTAGE is the nominal continuous voltage which may be applied without altering any characteristics. (Usually the max. applied volt. without causing arcing/damage is the WVDC x 200%). *TEMPERATURE COEFFICIENT (TC) is the change in capacitance per degree C. A NEGATIVE coefficient is a REDUCTION in C as the temp. INCREASES. *STABILITY (aging) is the change in capacitance over time, usually spec'd at 1000hrs. Aging decreases logarithmically and thus the majority of capacitance change due to aging occurs within the first 1000 hours. *DISSIPATION FACTOR (DF) is the ratio of energy dissipated to the energy stored in the capacitor. The DF is frequency sensitive and is usually specified at a given frequency. *QUALITY FACTOR (Q) is the ratio of energy stored to the energy dissi- pated, or the inverse of DF. Also specified at a given frequency. (Usually the dissipation factor OR the Q is specified, not both) *DIELECTRIC ABSORPTION is the amount of energy dissipated in the capacitor due to losses in the dielectric. NOTE: The importance of these dissipation factors is what percentage of the power (current and voltage) applied to the capacitor will be LOST due to the dielectric and electrode resistance. This loss is primarily converted into HEAT which will 1) change the capacitance of the device depending upon its temperature coefficient, and 2) can cause damage to the capacitor if its ratings are exceeded. At RF frequencies, the power dissipated is the PEAK-TO-PEAK values, which can be large! *INSULATION RESISTANCE (IR) is the DC resistance of the capacitor measured across the terminals. It is a function of the resistance in the metal electrodes and the resistance losses of the dielectric. Thus, the IR will be lower for higher values of C (since it consists of more metal and dielectric materials for higher capacitances). *EQUIVALENT SERIES RESISTANCE (ESR) is the sum of the electrode resistance plus the losses due to the dielectric. Dielectric losses are REACTIVE since losses are frequency sensitive. ESR represents the "real" part of the reactance (of the form "R+j"). ******** STANDARD VALUES OF CERAMIC AND FILM CAPACITORS TO 1uF ********* -------------------------------------- 10pF 100pF .001uF .01uF .10uF Not all standard values are 15 150 .0015 .015 .15 available in certain families of 22 220 .0022 .022 .22 capacitors or for all voltage 27 270 .0027 .027 .27 ratings. Some manufacturers 33 330 .0033 .033 .33 also have additional values. 47pF 470pF .0047uF .047uF .47uF 56 560 .0056 .056 .56 Always specify the tolerance 68 680 .0068 .068 .68 desired, otherwise the highest 75 750 .0075 .075 .75 (worst) tolerance will be 82pF 820pF .0082uF .082uF .82uF assumed! 1.0uF -------------------------------------- Common tolerance codes: -J 5% And, just a reminder: -K 10% -L 15% ******* ******* -M 20% * CAP * -----* CAP *----- ******* ******* ******* | | * CAP *------- | | AXIAL LEADS ******* RADIAL LEADS BROKEN LEAD ----------------------------------------------------------------------- GL de Paul NA5N (pharden@nrao.edu) From owner-qrp-l@Lehigh.EDU Wed Feb 12 17:56:11 1997 Received: from fidoii.CC.Lehigh.EDU (fidoii.CC.Lehigh.EDU [128.180.1.4]) by oucsace.cs.ohiou.edu (8.7.6/8.7.1) with ESMTP id RAA20489 for ; Wed, 12 Feb 1997 17:56:10 -0500 (EST) X-Received-x: from fidoii.CC.Lehigh.EDU (fidoii.CC.Lehigh.EDU [128.180.1.4]) by oucsace.cs.ohiou.edu (8.7.6/8.7.1) with ESMTP id RAA20489 for ; Wed, 12 Feb 1997 17:56:10 -0500 (EST) Received: from Lehigh.EDU ([127.0.0.1]) by fidoii.cc.lehigh.edu with SMTP id <35470-32579>; Wed, 12 Feb 1997 17:54:17 -0500 Received: from nss2.CC.Lehigh.EDU ([128.180.1.26]) by fidoii.cc.lehigh.edu with ESMTP id <35372-38722>; Wed, 12 Feb 1997 17:53:15 -0500 Received: from zia.aoc.nrao.edu (zia.aoc.nrao.edu [146.88.1.4]) by nss2.CC.Lehigh.EDU (8.8.5/8.8.5) with SMTP id RAA80589 for ; Wed, 12 Feb 1997 17:52:43 -0500 Received: (from pharden@localhost) by zia.aoc.nrao.edu (8.6.12/8.6.10) id PAA24412 for qrp-l@lehigh.edu; Wed, 12 Feb 1997 15:52:41 -0700 Message-Id: <199702122252.PAA24412@zia.aoc.nrao.edu> Date: Wed, 12 Feb 1997 15:52:41 -0700 Reply-To: pharden@aoc.nrao.edu Sender: owner-qrp-l@Lehigh.EDU Precedence: bulk From: Paul Harden To: "Low Power Amateur Radio Discussion" Subject: DATA SHEET: "nF" value Caps X-Listprocessor-Version: 8.0 -- ListProcessor(tm) by CREN Status: O I've received several emails inquiring about nF (nano Farads). Nano is 1x10EE-9 (.000 000 001 F). It is a unit of measure starting to see more use in both amateur and professional publications. Here's the "data sheet" on "nF" caps: 1nF = .001uF = 1000pF 10nF = .01uF 100nF = .1uF Good question; will have to add it to the data sheets on caps next time I post them. 72, Paul NA5N