1. Measurament systems in electronics Dr inż. ZDZISŁAW PÓLKOWSKI Polkowice, 2015 University of Pitesti Dolnośląska Wyższa Szkoła Przedsiębiorczości i Techniki w Polkowicach Damian Constantin

2. Topics Menu  Definition of measurament systems in electronics  Definitions of the SI base and derived units  Definitions of the SI base units  SI derived units  Other not SI units  Voltmeter  Analog Voltmeter  Digital Voltmeter  Oscilloscope  Analog ammeter  Digital ammeter  Digital-to-Analog Convertors (DAC)  Analog-to-Digital Convertos(ADC)  Frequency meter  Types of frequency  Ohmmetermeters

3. Definition of measurament systems in electronics Electronic Measurements Measurement of some electric, magnetic, or electromagnetic quantity or of the relationships between such quantities characterizing the operation of electronic equipment over the range of frequencies from the infrasonic to the superhigh. http://cie-wc.edu/Electronics-Technology-Troubleshooting.aspx

4. Definitions of the SI base and derived units The International System of Units, universally abbreviated SI (from the French Le Système International d'Unités), is the modern metric system of measurement. The SI was established in 1960 by the 11th General Conference on Weights and Measures (CGPM, Conférence Générale des Poids et Mesures). The CGPM is the international authority that ensures wide dissemination of the SI and modifies the SI as necessary to reflect the latest advances in science and technology. http://www.eformulae.com/physics/derived_units.php

5. Definitions of the SI base units https://www.boundless.com/chemistry/textbooks/boundless-chemistry- textbook/gases-5/properties-of-gases-50/si-units-of-pressure-253- 1861/ The SI is founded on seven SI base units for seven base quantities assumed to be mutually independent

6. SI derived units http://www.technick.net/public/code/cp_dpage.php?aiocp_dp=guide_si_units/ Other quantities, called derived quantities, are defined in terms of the seven base quantities via a system of quantity equations. The SI derived units for these derived quantities are obtained from these equations and the seven SI base units. For ease of understanding and convenience, 21 SI derived units have been given special names and symbols, as shown in Table. The special names and symbols of the 21 SI derived units with special names and symbols given in Table may themselves be included in the names and symbols of other SI derived units.

7. Other not SI units http://physics.nist.gov/cuu/Units/outside.html/ Bit: A bit is the smallest unit of data in a computer. A bit has a single binary value, either 0 or 1. Although computers usually provide instructions that can test and manipulate bits, they generally are designed to store data and execute instructions in bit multiples called bytes. In most computer systems, there are eight bits in a byte. The value of a bit is usually stored as either above or below a designated level of electrical charge in a single capacitor within a memory device. Half a byte (four bits) is called a nibble. In some systems, the term octet is used for an eight-bit unit instead of byte. In many systems, four eight-bit bytes or octets form a 32-bit word. In such systems, instruction lengths are sometimes expressed as full-word (32 bits in length) or half-word (16 bits in length). Decibel (dB): One tenth of the common logarithm of the ratio of relative powers, equal to 0.1 B (bel). Note 1: The decibel is the conventional relative power ratio, rather than the bel, for expressing relative powers because the decibel is smaller and therefore more convenient than the bel. The ratio in dB is given by dB = 10 log 10 (P 1 /P 2 )

8. Other not SI units http://www.bipm.org/en/publications/si-brochure/section4-2.html/ Neper (Np): A unit used to express ratios, such as gain, loss, and relative values. Note 1: The neper is analogous to the decibel, except that the Naperian base 2.718281828... is used in computing the ratio in nepers. Note 2: The value in nepers, Np, is given by Np = ln(x 1 /x 2 ), where x 1 and x 2 are the values of interest, and ln is the natural logarithm, i.e., logarithm to the base e. Note 3: One neper (Np) = 8.686 dB, where 8.686 = 20/(ln 10). Note 4: The neper is often used to express voltage and current ratios, whereas the decibel is usually used to express power ratios. Note 5: Like the dB, the Np is a dimensionless unit. Note 6: The ITU recognizes both units.

9. Voltmeter http://www.ibiblio.org/kuphaldt/electricCircuits/Exper/EXP_2.html/ A voltmeter, also known as a voltage meter, is an instrument used for measuring the potential difference, or voltage, between two points in an electrical or electronic circuit. Some voltmeters are intended for use in direct current (DC) circuits; others are designed for alternating current (AC) circuits. Specialized voltmeters can measure radio frequency (RF) voltage.

10. Analog Voltmeter A basic analog voltmeter consists of a sensitive galvanometer (current meter) in series with a high resistance. The internal resistance of a voltmeter must be high. Otherwise it will draw significant current, and thereby disturb the operation of the circuit under test. The sensitivity of the galvanometer and the value of the series resistance determine the range of voltages that the meter can display. http://www.directindustry.com/prod/circutor/product-11644-436892.html

11. Digital Voltmeter http://notebook.pege.org/2004-car-adapter/digital-voltmeter.htm/ A digital voltmeter shows voltage directly as numerals. Some of these meters can determine voltage values to several significant figures. Practical laboratory voltmeters have maximum ranges of 1000 to 3000 volts (V). Most commercially manufactured voltmeters have several scales, increasing in powers of 10; for example, 0-1 V, 0-10 V, 0-100 V, and 0-1000 V.

12. Oscilloscope An oscilloscope can be used to measure low voltages; the vertical displacement corresponds to the instantaneous voltage. Oscilloscopes are also excellent for the measurement of peak and peak-to-peak voltages in AC and RF applications. Voltmeters for measuring high potential differences require heavy-duty probes, wiring, and insulators. http://www.printcapture.com/

13. Analog ammeter Analog ammeters are metered instruments that measure current flow in amperes. They display current levels on a dial, usually with a moving pointer or needle. Analog ammeters provide information about current draw and current continuity in order to help users troubleshoot erratic loads and trends. They have both positive and negative leads and feature extremely low internal resistance. Ammeters are connected in series with a circuit (and never parallel) so that current flow passes through the meter. High current flow may indicate a short circuit, unintentional ground, or defective component. Low current flow may indicate high resistance or poor current flow within the circuit. http://www.directindustry.com/prod/ime/product-14561-56640.html

14. Digital ammeter In much the same way as the analogue ammeter formed the basis for a wide variety of derived meters, including voltmeters, the basic mechanism for a digital meter is a digital voltmeter mechanism, and other types of meter are built around this. Digital ammeter designs use a shunt resistor to produce a calibrated voltage proportional to the current flowing. This voltage is then measured by a digital voltmeter, through use of an analog to digital converter (ADC); the digital display is calibrated to display the current through the shunt. Such instruments are generally calibrated to indicate the RMS value for a sine wave only but some designs will indicate true RMS (sometimes with limitations as to wave shape). http://www.enertechdevices.com/products/digital_ammeter_48_X_96.php

15. Digital-to-Analog Convertors (DAC) As the world’s leading provider of data converters, Analog Devices has the industry’s largest portfolio of D/A converters (DACs) ranging from 8 bits to 24 bits. ADI DACs are unmatched in their ability to deliver performance and value by providing accurate and reliable conversion for a range of applications including industrial automation, programmable logic controllers, optical transceivers, data acquisition, and more. Our portfolio includes integrated output amplifier options for ease of use, dynamic range DACs for multicarrier generation over a very wide bandwidth, and a variety of other DACs to suit your design needs. http://www.analog.com/en/products/digital-to-analog-converters.html

16. Analog-to-digital Convertor(ADC) http://www.analog.com/en/products/digital-to-analog-converters.html Linear Technology offers a complete family of high performance analog to digital converter products (ADCs), including 16-bit to 24-bit delta sigma converters for precision measurements, up to 16-bit high-speed pipeline ADCs for communications and 8-bit to 20-bit low power successive approximation register (SAR) analog to digital converter for everything in between. Our analog to digital converter portfolio offers unmatched noise performance (SINAD, SNR and SFDR), low power consumption and small package size.

17. Frequency meter http://www.allaboutcircuits.com/textbook/alternating-current/chpt- 12/frequency-and-phase-measurement/ A frequency meter is an electronic instrument that displays the frequency of a periodic electrical signal. Frequency meter, device for measuring the repetitions per unit of time (customarily, a second) of a complete electromagnetic waveform. Various types of frequency meters are used. Many are instruments of the deflection type, ordinarily used for measuring low frequencies but capable of being used for frequencies as high as 900 Hz. These operate by balancing two opposing forces. Changes in the frequency to be measured cause a change in this balance that can be measured by the deflection of a pointer on a scale.

18. Types of frequency meters http://www.electronicecircuits.com/electronic-circuits/analog-frequency-meter-circuit Deflection-type meters are of two types, electrically resonant circuits and ratiometers. An example of a simple electrically resonant circuit is a moving- coil meter. In one version, this device possesses two coils tuned to different frequencies and connected at right angles to one another in such a way that the whole element, with attached pointer, can move. Frequencies in the middle of the meter’s range cause the currents in the two coils to be approximately equal and the pointer to indicate the midpoint of a scale. Changes in frequency cause an imbalance in the currents in the two coils, causing them and, in turn, the pointer to move. Another type of frequency meter, not of the deflection type, is the resonant-reed type, ordinarily used in ranges from 10 to 1,000 Hz, although special designs can operate at lower or higher frequencies. These work by means of specially tuned steel reeds that vibrate under the effect of electric current; only those reeds that are in resonance vibrate visibly, however.

19. Ohmmeter http://www.tigerstop.com/tigertamer/Using_an_Ohm_Meter.htm Though mechanical ohmmeter (resistance meter) designs are rarely used today, having largely been superseded by digital instruments, their operation is nonetheless intriguing and worthy of study. The purpose of an ohmmeter, of course, is to measure the resistance placed between its leads. This resistance reading is indicated through a mechanical meter movement which operates on electric current. The ohmmeter must then have an internal source of voltage to create the necessary current to operate the movement, and also have appropriate ranging resistors to allow just the right amount of current through the movement at any given resistance. Starting with a simple movement and battery circuit, let’s see how it would function as an ohmmeter: