Position: Index > 555 Circuit >

555 IC Oscillator with 50% Duty Cycle (LM2575)

2015-01-29 01:49  
Declaration:We aim to transmit more information by carrying articles . We will delete it soon, if we are involved in the problems of article content ,copyright or other problems.

This article describes the 555 IC Oscillator with 50% Duty Cycle (LM2575). The content is very simple, very helpful. Components in this article can help you understand better understanding of this article. For example, in this article, you can go to find and buy these components:LM2575.

A square wave oscillator using 555 IC can be configured to give symmetric oscillation (50% duty cycle). Other circuit uses diodes to split the charging and the discharging paths through different resistors, but here we need no such diodes. Here is the schematic diagram:

oscillator 555 50 duty cycle circuit schematic

The time period for the output high is the same as regular configuration,

t1 = 0.693 RA C,

but for the output low, the period is

t2=[(RA.RB/(RA RB)].C.Ln[(RB-2RA)/(2RB-RA)]

Thus the oscillator frequency is? equal to 1/(t1 t2).

Please remember this oscillator circuit will not oscillate if RB is greater than 1/2 RA because the junction of RA and RB cannot bring pin 2 down to 1/3 VCC and trigger the lower comparator.

Reprinted Url Of This Article: