resistorsschematics
I know that capacitors in parallel are used for filtering, but what could possibly a resistor in parallel be used for?
Take for example the schematics I pinned to this post http://i.stack.imgur.com/Y1Ttr.jpg and the resistor I circled in black what could possibly be its use??
I hope I've been clear enough, Thanks.
Schematics:
Schematics/circuit diagram conveys the electrical connection between different active and passive electrical components like resistors, capacitors, Integrated circuits IC. Schematics is readable and understandable format about the connectivity and functionality between different components. For e.g.
PCB:
Printed Circuit Board(PCB) is abbreviated as PCB or sometimes it is called as Printed Wiring Board(PWB). PCB is the physical representation of all the electrical connections between active and passive components used in the schematic. But readability and understating of PCB is complicated as compare to Schematic. For e.g.
I have tried to explain here in layman language. Going into detail of the PCB design there are different tools available like ALTIUM, ALLEGRO and many more.
PCB can be built using FR4 laminate or ceramic material.
FR4 Material Laminate:
Ceramic PCB:
As far as PCB Design is considered. PCB's can be single layer, 2 layer, 4 layer or even multi-layer with thickness of 0.8mm or 1.6mm or even more as per the numbers of layers. While designing the PCB specific stack-up is followed which defines Power layer, Ground layer and signal layer sandwiched between FR4 material with the core in between.
Example PCB stack-up:
This circuit is known as Bob-Smith termination. It is used to enhance EMI and ESD performance of the Ethernet circuit. The unused pairs are connected together through a 75Ω impedance matching circuit to chassis ground through a 0.001uF, 2 kV capacitor.The capacitor provides a discharge path for noise immunity on the unused pairs.
Also,termination for the media-side centre taps is comprised of individual capacitors(C3) to chassis ground.
Best Answer
The RC network circled in black is a power on reset circuit. I have attached a figure from an ST application note Simple Reset Circuits for the ST6
It is oppposite of the picture you attached, as this ST62XX is reset low instead of high voltage on the pin.
The purpose is to keep the device in reset until power rail has come all of the way up. The RC circuit has a time constant R*C that will create the delay.
The circuit in the blue circle is a simple pull up resistor on that EEPROM's write protect line, and the blue square appears to be a voltage divider to monitor the 3.3V line.