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61 Cards in this Set
- Front
- Back
What is this symbol?
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CELL - Supplies electrical energy.
The larger terminal (on the left) is positive (+). A single cell is often called a battery, but strictly a battery is two or more cells joined together. |
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What is this symbol?
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SINGLE POLE SINGLE THROW SWITCH (SPST) - An on-off switch allows current to flow only when it is in the closed (on) position.
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What is this symbol?
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PUSH TO BREAK SWITCH (PTBS) -This type of push switch is normally closed (on), it is open (off) only when the button is pressed
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What is this symbol?
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SINGLE POLE DOUBLE THROW SWITCH (SPDT) - A 2-way changeover switch directs the flow of current to one of two routes according to its position. Some SPDT switches have a central off position and are described as 'on-off-on'.
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What is this symbol?
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DOUBLE POLE DOUBLE THROW SWITCH (DPDT) - This switch can be wired up as a reversing switch for a motor. Some DPDT switches have a central off position
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What is this symbol?
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PUSH TO MAKE SWITCH (PTMS) -
A push switch allows current to flow only when the button is pressed. This is the switch used to operate a doorbell. |
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What symbol is this?
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PIEZO TRANSDUCER - A transducer which converts electrical energy to sound.
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What symbol is this?
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VARIABLE RESISTOR - This type of variable resistor with 2 contacts (a rheostat) is usually used to control current. Examples include: adjusting lamp brightness, adjusting motor speed, and adjusting the rate of flow of charge into a capacitor in a timing circuit.
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What symbol is this?
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POTENTIOMETER - This type of variable resistor with 3 contacts (a potentiometer) is usually used to control voltage. It can be used like this as a transducer converting position (angle of the control spindle) to an electrical signal.
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What symbol is this?
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ELECTROLYTIC CAPACITOR -
A capacitor stores electric charge. This type must be connected the correct way round. A capacitor is used with a resistor in a timing circuit. It can also be used as a filter, to block DC signals but pass AC signals. |
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What symbol is this?
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THYRISTOR - A Thyristor (silicon controlled rectifier or SCR) is a little like a transistor. When a small current flows into the GATE (G), this allows a larger current to flow from the ANODE (A) to the CATHODE (C). Even when the current into the gate stops the thyristor continues to allow current to flow from anode to cathode this is called LATCHING.
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What symbol is this?
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DIODE - A diode allows electricity to flow in one direction only and blocks the flow in the opposite direction. They may be regarded as one-way valves and they are used in various circuits, usually as a form of protection.
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What symbol is this?
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NPN TRANSISTOR - A transistor amplifies current. It can be used with other components to make an amplifier or switching circuit.
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What symbol is this?
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FIELD-EFFECT TRANSISTOR (FETs) -are digital switches that respond to an input voltage to allow an increase in either voltage or current
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What symbol is this?
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NOT GATE - NOT gate (also often called Inverter) is a logic gate. It takes one input signal. The NOT gate inverts (changes round) the signal. The output will be 1 when the input is 0 and vice versa
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What symbol is this?
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RESISTOR - A resistor restricts the flow of current, for example to limit the current passing through an LED. A resistor is used with a capacitor in a timing circuit.
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What symbol is this?
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CAPACITOR - A capacitor stores electric charge. A capacitor is used with a resistor in a timing circuit. Capacitor can be used to smooth current flow across a power supply
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What symbol is this?
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RELAY - An electrically operated switch that enables one electrical circuit to switch on a second circuit without an electrical connections between the two circuits.
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What symbol is this?
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LIGHT DEPENDENT RESISTOR (LDR) -An LDR is a special type of resistor. The resistance changes accordingly to the amount of light shining directly onto it.
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What symbol is this?
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AND LOGIC GATE - The output will be 1, when the inputs A andB are both 1.
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What symbol is this?
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NAND LOGIC GATE - The truth table for a NAND gate is the opposite of the AND gate.
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What symbol is this?
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OR LOGIC GATE - The output will be 1 when the inputs A or B are both 1 or both inputs are 1.
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What symbol is this?
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NOR LOGIC GATE - The truth table for a NOR gate is the opposite of the OR gate.
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What symbol is this?
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XOR LOGIC GATE - The exclusive OR gate is a true OR function. The output will be 1 when the inputs A or B are 1.
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What symbol is this?
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555 Timer - The 555 Integrated Circuit (IC) is an easy to use timer that has many applications. Can be used in MONOSTABLE or ASTABLE circuits.
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What symbol is this?
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ANMETER - An ammeter is used to measure current (I).
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What symbol is this?
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VOLTMETER - A voltmeter is used to measure voltage (V)
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What symbol is this?
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EARTH - A connection to earth. For many electronic circuits this is the 0V (zero volts) of the power supply, but for mains electricity and some radio circuits it really means the earth. It is also known as ground.
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What symbol is this?
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BATTERY - Supplies electrical energy. A battery is more than one cell. The larger terminal (on the left) is positive (+).
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What symbol is this?
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BULB/LAMP - A transducer which converts electrical energy to light. This symbol is used for a lamp which is an indicator, for example a warning light on a car dashboard.
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What symbol is this?
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LIGHT EMITTING DIODE - LED's are a special type of diode which emits light when current flows through it. LEDs are polarised components. they must be the correct way round in a circuit to conduct electricity and light up. The anode leg is positive and the cathode leg the negative. the LED normally has two identify features to indicate its polarity: anode leg is longer and cathode had a flat side on the casing.
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What symbol is this?
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BUZZER - A polar component that changes electrical energy into sound.
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What symbol is this?
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SOLENOID - A coil of wire which creates a magnetic field when current passes through it. It may have an iron core inside the coil. It can be used as a transducer converting electrical energy to mechanical energy by pulling on something.
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What symbol is this?
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MOTOR - A transducer which converts electrical energy to kinetic energy (motion).
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What symbol is this?
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7 SEGMENT DISPLAY - Each display contains seven separate LEDs arranged in a pattern to form a number from 0 to 9 and an extra LED for the decimal point.
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Units of Current
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AMP
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Units of Resistance
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OHMS
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Units of Voltage
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VOLT
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Units of Capacitance
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FARAD
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Resistance in Series
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R Total = R1 + R2 + R3
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Resistors in Parallel
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R Total = R1 x R2 / R1 + R2
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Time Period
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Time Period = Resistance x Capacitance
T = R x C |
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Ohms LAW
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Voltage = Current x Resistance
V = I x R R = V / C C = V / R |
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What symbol is this?
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FUSE - The fuse breaks the circuit if a fault in an appliance causes too much current flow. The fuse contains a piece of wire that melts easily. If the current going through the fuse is too great, the wire heats up until it melts and breaks the circuit.
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What symbol is this?
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THERMISTOR - A thermistor is a type of resistor. its resistance changes according to temperature. A thermistor converts changes in temperature into changes in electric current.
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What symbol is this?
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PHOTOTRANSISTOR - A phototransistor is a device that converts light energy into electric energy and produce both current and voltage.
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What symbol is this?
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OPTO - ISOLATOR - Is a component that transfers electrical signals between two isolated circuits by using light. Opto-isolators prevent high voltages from affecting the system receiving the signal.
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What symbol is this?
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Operational Amplifier (OP-AMP) - amplifies the difference between the two inputs to produce a voltage gain as high as 100,000 times the difference. The output voltage cannot be any greater than the power-supply voltages.
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What is this symbol?
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BELL - A component that changes electrical energy into sound.
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What is this symbol?
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VOLTAGE RAILS - These are very common when designing circuits and show the voltage of the circuit.
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What is this symbol?
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FLASHING LIGHT EMITTING DIODE - LED's are a special type of diode which emits light when current flows through it. LEDs are polarised components. they must be the correct way round in a circuit to conduct electricity and light up. The anode leg is positive and the cathode leg the negative. the LED normally has two identify features to indicate its polarity: anode leg is longer and cathode had a flat side on the casing.
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What is this symbol?
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MICROPHONE - A microphone is an acoustic-to-electric transducer or sensor that converts sound in the air into an electrical signal.
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What is this symbol?
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BI-COLOUR LIGHT EMITTING DIODE - LED's are a special type of diode which emits light when current flows through it. LEDs are polarised components. they must be the correct way round in a circuit to conduct electricity and light up. The anode leg is positive and the cathode leg the negative. the LED normally has two identify features to indicate its polarity: anode leg is longer and cathode had a flat side on the casing.
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What is this symbol?
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TRI-COLOUR LIGHT EMITTING DIODE - LED's are a special type of diode which emits light when current flows through it. LEDs are polarised components. they must be the correct way round in a circuit to conduct electricity and light up. The anode leg is positive and the cathode leg the negative. the LED normally has two identify features to indicate its polarity: anode leg is longer and cathode had a flat side on the casing.
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What is this symbol?
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LOUDSPEAKER - A loudspeaker is an electroacoustic transducer that produces sound in response to an electrical audio signal input. In other words, speakers convert electrical signals into audible signals.
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What is this symbol?
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VOLTAGE REGULATOR - A voltage regulator is designed to automatically maintain a constant voltage level.
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What is this symbol?
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CROSSING OF CONDUCTERS - The lines in all but the simplest of electronics schematic diagrams will at some places need to cross over each other. When they do, it's vital that you can tell whether the lines that cross represent actual connections (also called junctions) between the conductors or the lines cross over each other but don't actually connect
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What is this symbol?
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JOINED CONDUCTORS - This is when tracks within a circuit are connected together.
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What is this circuit?
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Operation Amplifier (OP-Amp) and 555 IC Astable Circuit: the op-amp is controlling the 555 IC astable circuit by providing a voltage to pin 4 of the astable. When pin 6 of the op-amp is high, the LED’s will flash. When pin 6 of the op-amp is low, pin 4 on the 555 IC resets the output back to 0V and the LED 1 stays lit.
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What is this circuit?
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Astable Circuit: When an astable circuit is first switched on, the capacitor C1 is not charged up. The voltage across the capacitor is less than one-third of the battery voltage, which causes pin 3 to be high. Capacitor C1 charges through the resistors R1 & R2 and is greater than two-thirds of the battery, which takes pin 3 to 0V. Capacitor C1 then discharges through R2 into pin 7 and when this happens, the output at pin 3 changes from OV to high, which makes the LED’s flash. The LED’s will flash repeatability until the circuit is switched off.
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Monostable Circuit: 555 IC is in a monostable state until the PTMS is pressed. This takes pin 2 to OV and pin 3 goes high and switches the LED on for a period of time, set by the resistor and capacitor connected to pins 6 & 7. After the period of time, it always returns to the monostable state.
Remember NOTCH or DOT identify pin 1 and opposite pin 1 is pin 8 |
