Introduction to CD4047

CD4047 is a CMOS Low Power monostable/astable multivibrator mainly used for converting DC current signal to AC signal. It comes with a high voltage rating around 20-V.

CD4047 is a 14 pin IC that operates on a logic techniques with an ability to allow negative or positive edge-triggered monostable multivibrator action layered with retriggering and external counting options.

Accurate and complemented buffered output with low power consumption make this IC an ideal choice for Frequency Division and Time Delay applications.


The internal power-on reset circuit is added on the IC and fast recovery time makes it an independent from the pulse width.

There is a sheer difference involved when IC works in monostable and astable mode. In monostable mode, the inverter needs a trigger signal for generating the output pulse, but an astable multivibrator doesn’t require trigger signal for every output pulse. More often than not, an astable multivibrator can be called as an oscillator

CD4047 Pin Description

As mentioned e there are 14 pins on the IC interface with every pin is used with a specific purpose



    

Pin Name
1  C:- Connected to an external capacitor
2  R:-  Connected to an external resistor
3 R-C Common:-   Common pin for       establishing a connection with resistor and capacitor
4 Astable:-  Must be kept low when used in astable mode
 
5 Astable:- Must be kept low when used in astable mode
6.+Trigger :-High to Low transition will be given to this pin when used in Monostable mode
7 VSS :- Ground pin

8 -Trigger:- Low to high transition will be given to this pin when used in Monostable mode
9 EXT Reset:- External reset triggers when a high pulse is provided to this pin, resetting the output Q to low and Q’ to high
10 Q :- Generate high o/p
11 Q' :-  It is an a inverse o/p of pin 10, producing a low out put
12 Retrigger:- This pin is used in Monostable mode for simultaneously retriggering +trigger and –trigger pin
13 OSC output:- Generate oscillated output
14 Vdd:- voltage supply pin

INVERTER USING CD4047 
TO Make 100W inverter using CD4047 we need to operate DC4047IC In Astable mode



,the inverter needs a trigger signal for generating the output pulse. The output frequency is determined when a single capacitor is connected between PIN 2 and 3.
The IC will be operating is an Astable mode when we apply  HIGH on Pin 5 and LOW on Pin 4, generating the output toggling between HIGH and LOW.

The oscillated output frequency on Pin 13 can be determined using the following formula

F = 1 / 4.4 x R*C

Similarly, the formula to find the time it takes to generate pulse will be given as:

t = 2.48 x R*C