Electronic Projects, forums and more.

Go Back   Electronic Circuits Projects Diagrams Free > Electronics Categories > Alternative Energy


Alternative Energy Discussion relating to the design and implementation of alternate energies.

Reply
 
Thread Tools Display Modes
Old 29th April 2008, 10:40 AM   (permalink)
C47
New Member
C47 is on a distinguished road
Default

arrgghhh!!!

the legs work separately but when i put the whole thing it doesnt work....i think that the timer cannot drive all four...
C47 is offline   Reply With Quote
Old 29th April 2008, 10:49 AM   (permalink)
Experienced Member
mvs sarma is a name known to allmvs sarma is a name known to allmvs sarma is a name known to allmvs sarma is a name known to allmvs sarma is a name known to allmvs sarma is a name known to all
Send a message via MSN to mvs sarma Send a message via Yahoo to mvs sarma
Default

Quote:
Originally Posted by C47
arrgghhh!!!

the legs work separately but when i put the whole thing it doesnt work....i think that the timer cannot drive all four...
legs drive 2 transistors only at any time
now worry. please take care of base current needs by managing the series base resistor.
555 has adequate capacity.
__________________
Regards,
Sarma.

Last edited by mvs sarma; 30th April 2008 at 02:52 AM.
mvs sarma is offline   Reply With Quote
Old 29th April 2008, 11:58 AM   (permalink)
Experienced Member
 
ericgibbs is a splendid one to beholdericgibbs is a splendid one to beholdericgibbs is a splendid one to beholdericgibbs is a splendid one to beholdericgibbs is a splendid one to beholdericgibbs is a splendid one to beholdericgibbs is a splendid one to beholdericgibbs is a splendid one to behold
Default

Quote:
Originally Posted by C47
arrgghhh!!!

the legs work separately but when i put the whole thing it doesnt work....i think that the timer cannot drive all four...
hi,
The circuit you have built, NOT simulated, does it have the 10K resistor as the load or the motor and is it the last circuit you posted.?

If its a motor, whats it voltage and current rating.? The 20K/10K base resistor look too higher a value.

The 555 should be able to drive that bridge with no problem.
__________________
Eric
"Good enough is Perfect"

PIC tutorials:
Gramo's: www.digital-diy.net/
Bill's: www.blueroomelectronics.com/
ericgibbs is online now   Reply With Quote
Old 29th April 2008, 06:57 PM   (permalink)
Experienced Member
mneary is a glorious beacon of lightmneary is a glorious beacon of lightmneary is a glorious beacon of lightmneary is a glorious beacon of lightmneary is a glorious beacon of light
Send a message via AIM to mneary
Default

At extremely low currents, emitter and collector of many BJTs are almost interchangeable. This is one of the traps of simulation.

Lesson: Simulate with your intended load!
mneary is offline   Reply With Quote
Old 1st May 2008, 05:32 AM   (permalink)
C47
New Member
C47 is on a distinguished road
Default

well its done....a 555 timer with an inverting buffer driving four NPN H-Bridge...it didnt work the first time coz of the base resistances...and also becoz the inverting buffer had popped (the second time)...so my 12VDC power supply showed a short circuit

it works.... finally

thankyou very much everybody
C47 is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes


Similar Threads
Thread Thread Starter Forum Replies Latest
Using Oscilloscopes mechie Electronic Theory 9 29th November 2007 09:48 PM
Button Debounce Coding help Suraj143 Micro Controllers 25 4th August 2007 09:48 AM
Define Linear Devices & Switch Mode Power Supplies? Suraj143 General Electronics Chat 17 9th July 2007 02:15 AM
Square wave AC? grrr_arrghh General Electronics Chat 9 19th February 2004 09:27 PM
some asembly coding help needed 1000hz square wave ? waqar Micro Controllers 10 13th April 2003 08:52 AM



All times are GMT. The time now is 05:44 PM.


Electronic Circuits  |  Radio Controlled
Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2008, Jelsoft Enterprises Ltd.