Be specific because a cap and a resistor are used everywhere. One "classical" use of caps is it blocks DC. Caps have the principle that it does not permit instantenious change of voltage. It stores energy.
In PCB design, DC blocking capacitor is not accurate, it should be 'RC network'. And the 'RC network' 1,work as a low pass filter to filter the unwanted RF signal on pcb, refer to basic circuit principles 2, work as a little battery, when the power supply is far from IC, the capacitor can supply the IC in time. Is it helpful to you?
u can use a cap to filters, to couple one block to other, to improve your BW, to feedback, etc. if u want to know when to use caps, first read in common literatures about your application, and then, look if u need to use caps.
- Used together with inductors on LC filters for radio tuning (usually variable capacitors)
- Used as components in oscillators circuits (RC dephasing networks, as load capacitance for crystals, feedback network, relaxation circuits, etc).
- As reservoir for pump charges, to maintain power in backup and low power circuits (e.g. supercapacitors to keep the memory of radio station tuning in receivers).
Capacitor is widely used for ac coupling between stages of amplifiers. This capacitor will isolate the dc biasing voltage while let the ac signal to pass through.
Well... Capacitors are devices capable of storing Electrical Energy in the form of Electric fields. They find application in various devices including: filters, bypass capacitors, coupling capacitors, oscilators, etc.
capacitors store the energy and after that they can release energy at apprpriate conditions.......... This is used in many cases... So there are many applications like
power decoupling, ac coupling, filters, timers, function generators, oscillators and terminations etc..
In power syatem, for power factor improvement also it will be used.......
- Used together with inductors on LC filters for radio tuning (usually variable capacitors)
- Used as components in oscillators circuits (RC dephasing networks, as load capacitance for crystals, feedback network, relaxation circuits, etc).
- As reservoir for pump charges, to maintain power in backup and low power circuits (e.g. supercapacitors to keep the memory of radio station tuning in receivers).
hi
u dont specify the type of circuit.
in amplifier circuits capacitors are mainly used to block DC to avoide level shifting.
it uses for coupling the multistage amplifier. the use of capacitor depends on need.
it also enhances bandwidth n some cases(CE degenerative).