suggestion on IC's with higher current carrying capacities for Pulse Width Modulation

[hasan.kamal]

hello. i require a suggestion for an IC used for PWM. right now i am working with 555 for generating a pulsating DC output but the issue is that 555 only allows a current of 200 mA. If it is possible can anyone help me out to know about wht i can use to replace this 555 so that i can play with the currents upto 1A.

Thank you

 

[Zanderist]

Have the pulses from this 555 drive a high current transistor.

 

[hasan.kamal]

hey..
i have actually tried that but i am unable to control the amplification of the current as it WILL give hfe^2 times the current even if it is not required... so are there any IC havin current rating of atleat 1 A which can give me a pulsed DC op atleast...?

 

[Zanderist]

I'd say reduce the current entering the base of the transistor then.

Another idea is use a transistor powered by the 555 supply of say 6 volts, then have the transistor drive a relay.

I don't think a direct connection from the 555 timer to the relay will work because you wouldn't develop the current needed to pull the contact in.

 

[hasan.kamal]

no sir i tried that also but in the end it was all to complicated i also tried a lot many types and combination of transistors but the results were not that satisfactory. are you aware of any IC with a higher A rating. i am asking this again n again as i am unaware of any other way to increase the current, if you have any other suggestion u can put that forward also. thank you sir.

 

[Zanderist]

I also know with the mircocontroller 'Arduino' which is capable of pwm you need to use a h-bridge.

https://www.mouser.com/knowledge/rohmsemiconductor/rohmhbridgedrivers/

I've also realized that a relay wouldn't work because of chattering which might cause arcing, in addition to that, the time required for the magnetic field to decay.

Another idea I just thought of is use of a SCR, though I don't think it would do nice things to the 555 timer.

 

[hasan.kamal]

ok sir. jus to check by SCR u mean Semiconductor controlled rectifier right ? i havnt worked wit it yet but i think its somwht like a Zener diode. if u have any related circuits please help me out with those also. thank u

---------- Post added at 22:21 ---------- Previous post was at 22:21 ----------

also i am tryin to remove the 555 completed from the circuit and hence need a new ic

 

[Zanderist]

Yes that's what I mean by SCR, I've haven't used one myself.

I don't think you should remove the 555 timer considering it's size, if you got an IC that could handle 1 amp, you will need to heat sink it.

 

[andre_luis]

hasan,

what device do you intend to drive with the PWM control ?

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