# RF Wireless World

## Home of RF and Wireless Vendors and Resources

One Stop For Your RF and Wireless Need

## 555 timer calculator-Monostable calculator,Astable calculator

This page covers 555 timer calculator including monostable calculator and astable calculator. In monostable mode, 555 timer calculator calculates pulse width and in astable mode, 555 timer calculator calculates frequency and period.

### 555 timer calculator | 555 timer monostable calculator

As mentioned this 555 timer monostable calculator is used to calculate pulse width based on R and C inputs.

Resistance in KΩ (input1) :

Capacitance in µF (input2) :

Output Pulse Width in sec (output1) :

EXAMPLE#1 555 timer calculator in monostable mode:
INPUTS: R = 10 KΩ , C = 47 µFarad ,
OUTPUT: Output pulse width, Tp = 0.517 sec

### 555 timer calculator in monostable mode formula or equations

Following equations or formulas are used for 555 timer calculator in monostable mode. Length of output pulse or pulse width (Tp) = 1.1*R*C
The R and C are shown in the figure.

### 555 timer calculator | 555 timer astable calculator

As mentioned this 555 timer astable calculator is used to calculate frequency, period, high time and low time based on C, R1, R2 inputs.

Capacitance (C1) in µF (input1) :

Resistance (R1) in KΩ (input2) :

Resistance (R2) in KΩ (input3) :

Time High, sec (output1) :

Time Low , sec (output2) :

Pulse Frequency, Hz (output3) :

Pulse Period, sec (output4) :

Duty Cycle, % (output5) :

EXAMPLE#2: 555 timer calculator in astable mode:
c1=100µF, R1=R2=10 Kohm
tHIGH = 1.386 sec , tLOW = 0.693 sec, Pulse Frequency= 0.481 Hz , Pulse Period = 2.079 sec , Duty cycle = 66.67%

### 555 timer calculator in astable mode formula or equations

Following equations or formulas are used for 555 timer calculator in astable mode. tHIGH = 0.693*C1*(R1+R2)
tLOW = 0.693*C1*R2
Pulse Frequency = 1/(tHIGH + tLOW)
Pulse Period = 1/Pulse Frequency
Duty Cycle = (R1+R2)/(R1+2*R2)

### Useful converters and calculators

Following is the list of useful converters and calculators.

dBm to Watt converter
Stripline Impedance calculator
Microstrip line impedance
Antenna G/T
Noise temp. to NF

### RELATED LINKS

Refer Ohm Law
Refer Inductor basics
Refer Resistor basics
Refer Capacitor basics