Pin Description 555 Timer Pinout IC
Developed by Signetics, an American company Timer 555 is used widely in digital circuits due to its cost effectiveness, low price, easy to implementation with stable function called stability. It is made with bipolar and CMOS types with low power material. One very simple low cost and much used timer chip used in digital electronics 
with sole purpose of generating pulse generation, generating high and low signals with time difference depends on our applications, is low and high pulse generation is called oscillator used in digital circuit as pulse specially in microcontrollers or pulse is used to switch on and off any device.
Diagram and Pin Details IC 555
With the help of various components like transistors, diodes, resistors and other components, we can design working of IC 555 timer. Operating voltage of IC is from 4 volts to 15 DC power supply. IC consists of flip flops voltage divider and electronic comparator used to compare voltage operations. Using this compartor the major role of IC 555 is to generate pulse with exact timings. So we can generate accurate timing pulses using IC. Timer IC is used with various timing operations like Astable, Monostable and Bistable multivibrators. Depends on the application of digital electronics we can use any of them.
PinOuts of IC 555 Timer
- Pin 1. – Negative voltage pin used to connect negative 0 volt of power supply.
- Pin 2. – Trigger pin, a negative pulse input used to provide signal to comparator. Then it sets Flip flip, causing the the ouput From 0 to 1, Low to high.
- Pin 3. – Its the ouput pin can run any Transistor To Transistor circuit, can sink or source current.
- Pin 4. – A Reset Pin used to reset the internal circuitry and flip flop which controls the output on pin number 3. It is an active low pin.
- Pin 5. – A control voltage pin used to control the timings of IC 555 by voltage divider network circuit.
- Pin 6. – A Threshold pin used to provide positive input signal to comparator number 2. Threshold pin used to reset the internal flip flop, when applied voltage cross 2/3 Vcc cause the output switch from 1 to 0 means High to Low status. This pin is directly connected to the RC Timing Circuit.
- Pin 7. – Discharge Pin is used to discharged the timing capacitor/filter to ground in case the output at pin number 3 changes to LOW states.
- Pin 8. – Supply +Vcc, A power supply positive edge of the is connected to this pin makes it working, operational voltage of the chip varies from 4.5 Volts to 15 Volts.
