resist the flow of current

1. PCB
(Research and innovation lab)
• This kids education of electronics and nature.
Samiksha S. Padgilwar

2. Registor
Resistors are used to reduce current flow.

3. Symbol

4. we used Resistor?
It Resist the current flow.

5. What is resistor and its function?
• A resistor is a passive two-terminal electrical component that implements
electrical resistance as a circuit element.
• In electronic circuits, resistors are used to reduce current flow, adjust signal levels,
to divide voltages, bias active elements, and terminate transmission lines, among
other uses.
Axial-lead resistors on tape. The
component is cut from the tape
during assembly and the part is
inserted into the board.

6. What are examples of resistors?
• Resistors are what are called “Passive Devices”, that is they contain no source of
power or amplification but only attenuate or reduce the voltage or current signal
passing through them. This attenuation results in electrical energy being lost in the
form of heat as the resistor resists the flow of electrons through it.
• . Resistors can also be connected together in various series and parallel
combinations to form resistor networks which can act as voltage droppers, voltage
dividers or current limiters within a circuit.

7. fixed Resistor
All modern fixed value resistors can be classified into four broad groups:
1)Carbon Composition Resistor – Made of carbon dust or graphite paste, low wattage
values
2)Film or Cermet Resistor – Made from conductive metal oxide paste, very low
wattage values
3)Wire-wound Resistor – Metallic bodies for heatsink mounting, very high wattage
ratings
4)Semiconductor Resistor – High frequency/precision surface mount thin film
technology

8. Carbon Composition Resistor
• Carbon resistors are a cheap general purpose resistor used in electrical
and electronic circuits.
• Their resistive element is manufactured from a mixture of finely ground
carbon dust or graphite (similar to pencil lead) and a non-conducting
ceramic (clay) powder to bind it all together.

9. Film or Cermet Resistor
The generic term “Film Resistor” consist of Metal Film, Carbon Film and Metal
Oxide Film resistor types, which are generally made by depositing pure metals,
such as nickel, or an oxide film, such as tin-oxide, onto an insulating ceramic
rod or substrate.
film types of resistor
Film Resistor
The resistive value of the resistor is controlled by increasing the desired
thickness of the deposited film giving them the names of either “thick-film
resistors” or “thin-film resistors”.

10. Wirewound Resistor
Wirewound Resistor is made by winding a thin metal alloy wire (Nichrome)
or similar wire onto an insulating ceramic former in the form of a spiral
helix similar to the film resistor above.
Wirewound Resistor
These types of resistor are generally only available in very low ohmic high
precision values (from 0.01Ω to 100kΩ) due to the gauge of the wire and
number of turns possible on the former making them ideal for use in
measuring circuits and Wheatstone bridge type applications.

11. Resistor do You like More?

12. Resistor colour code

13. Resistors in Series
• Resistors are said to be connected in “Series”, when they are daisy chained
together in a single line.
• Resistors in series have a Common Current flowing through them as the current
that flows through one resistor must also flow through the others as it can only
take one path.

14. Series Resistor Circuit
• As the resistors are connected together in series the same
current passes through each resistor in the chain.
• The total resistance, RT of the circuit must be equal to the
sum of all the individual resistors added together.

15. Series Resistor Voltage
VAB = VR1 + VR2 + VR3 = 9V.
Using Ohm’s Law, the voltage across the individual
resistors can be calculated as:
Voltage across R1 = IR1 = 1mA x 1kΩ = 1V
Voltage across R2 = IR2 = 1mA x 2kΩ = 2V
Voltage across R3 = IR3 = 1mA x 6kΩ = 6V

16. Resistors in Series Example No1

17. Voltage Divider

18. Thank You!