I'll start off by saying im very new to electronics and this is the first thing ive built so far. ive made an injector driver circuit using basically two data sheets for the 2 ic im using, but i have read that data sheets can be not ideal circuits though. im wondering if there are any changes people would make to this circuit or if it looks good. i may have added things that are not needed or are wrong, im not sure exactly what im doing. although i did get this circuit working. my breadboard pic is different then my circuit drawing, instead of 14.5v its 5v off the arduino, instead of an injector i have an led.

also i made a thread about making a cdi, that explains what im trying to do over all. this project will at all times be 100% stationary even after completion http://forum.allaboutcircuits.com/threads/mosfet-driven-cdi-design-help.104857/

here are the pics also C6 is 0.1uf

 

does any one have any input on this circuit or comments or recamandations on how to make it better or should it function as planed. i want to get a pcb board printed so i want to know if this is good

 

Circuit looks good. Straight off the datasheet.

 

yes it is lol i added a cap from power in to ground on the 1949 and i added two 10uf caps on the 7805. for some reason i was under the impression that data sheets comonly used very simple circuits to show how to test the chip and may not be ideal for project use or missing decoupling caps.
thanks, also if you were doi g this woukd you use the data sheet for circuit or make your own. should i say away from directly using data sheet circuits?

 

I noticed the decoupling cap at the supply pins. Good practice. If using an unfamiliar IC I would start with any 'typical application circuit' shown on its datasheet, but take into account any text/footnotes etc about operating parameters and modifications. I would also ask myself "why have they done that, chosen that value?"

 

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I would also ask myself "why have they done that, chosen that value?"

That's a very good question but it's complicated by the fact that certain component values are somewhat arbitrary, such as decoupling capacitors.
And sometimes it's difficult to determine whether that's true or not for any particular component.

 

Alac_t that is the number one way im learning about electronics. i find circuits similer to what i need. then i look them over trying to figure out why they used things in the places they did. some things make sence and other i just cant figure out why they did.but some times its hard to figure out why they used somthing and if its needed. and i also run into the problem crutschow pointed out. its starting to make more sence to me now. i know why some things are used and other i csn guess why it was.
i wish i could find example circuits that have a list of components and discriptions of why they are there and what they do.

 

It's not always possible to deduce why a particular component value is shown on a datasheet. Likely it was arrived at after extensive lab testing by the manufacturer. The end user of components has to take some things on trust. Given plenty of time and equipment one could experiment with other values and compare results.

 

yes it is lol i added a cap from power in to ground

What does it means?

 

yes, it is stright off the datasheet and i chuckled as i was typing that. not sure if your just against internet slang or acutally dont know. if there was a smily for it and i wasnt on my phone i could have used that instead
the other part was missing a comma, it should have said 'i added a cap from power in, to ground.

 

OK I see.