What is a 555 Timer?

The 555 timer is an integrated circuit chip that is often used in timers, pulse generators, and oscillator circuits. 555 can be used as a delay device, trigger or start-up element in the circuit.

The 555 timer was designed by Hans R. Camenzind for Sigmanatic in 1971. Signitic was later acquired by Philips.

555 chips produced by different manufacturers have different structures. There are 25 standard 555 chips integrated.

The functions of each pin of the 555 chip in DIP package are shown in the following table: ^[2]

The 555 timer can work in three working modes:

• Monostable mode: In this mode, the 555 function is a single trigger. Applications include timers, pulse loss detection, bounce switches, tact switches, frequency dividers, capacitance measurements, and pulse width modulation (PWM).

• Astable mode: In this mode, the 555 operates as an oscillator. The 555 chip in this operating mode is often used in strobe lights, pulse generators, logic circuit clocks, tone generators, and pulse position modulation (PPM). If used

  The following are the electrical parameters of NE555. Other 555 timers with different specifications may have different parameters. Please refer to the data sheet.

  Supply voltage ( V CC )	4.5-16 V
  Rated operating current ( V CC = +5 V)	3-6 mA
  Rated operating current ( V CC = +15 V)	10-15 mA
  Output current	200 mA
  Maximum power consumption	600mW
  Lowest working power	30mW (5V), 225mW (15V)
  temperature range	0-70 ° C

  The 555 timer has many derivative models made by different companies, including models with different pin functions,

  • Operational Amplifier

  • Oscillator

  • RC circuit