[klotzy_550]

Anybody have any good recommendations? Most Mosfets (that seem like they would work) that I find are discontinued or need a minimum of 2500 pieces. I figured somebody on here has a good recommendation for such a driver.

-Thanks!

[edc_atl]

We use the NCV8403 for some time now without problems. We make a 4-channel injector driver board for the MS crowd that has proven quite useful, durable and inexpensive. It is not our design but it is very cost effective.

Enclosed is a picture of the board and the NCV8403 datasheet.

[klotzy_550]

Thanks for the quick reply!

Could you explain the reason for the resistor on the source? and the purpose of the diode? is it to ensure the voltage remains in a certain range or to prevent unwanted feedback on the digital pin?

[edc_atl]

Thanks for the quick reply!

Could you explain the reason for the resistor on the source? and the purpose of the diode? is it to ensure the voltage remains in a certain range or to prevent unwanted feedback on the digital pin?

It is a crowbar circuit for transient voltage suppression. Works very well and keeps the other electronics spike free.

Again, it is not our design but it works very very well.

[klotzy_550]

Thanks again, that makes more sense now! That is what I was figuring with the diode, never seen that before with the resistor on the source. However, this is exactly what I was looking for!

[PSIG]

While not as individually economical (offhand 15-20A at $1.15 ea); would using an IGBT be a lower parts count (no TVSs) and possibly interchangeable with ignition parts for lower cost as well? Just thinking out loud. Dangerous.

David

[klotzy_550]

While not as individually economical (offhand 15-20A at $1.15 ea); would using an IGBT be a lower parts count (no TVSs) and possibly interchangeable with ignition parts for lower cost as well? Just thinking out loud. Dangerous.

David

From the research I did on it, using an IGBT for an injector driver (to increase parts commonality, lower unit price) is not as efficient as using a mosfet to control the lower voltages. http://www.irf.com/technical-info/white ... wisely.pdf provides good information on this.

[klotzy_550]

Thanks again, that makes more sense now! That is what I was figuring with the diode, never seen that before with the diode on the source. However, this is exactly what I was looking for!

[edc_atl]

Thanks again, that makes more sense now! That is what I was figuring with the diode, never seen that before with the diode on the source. However, this is exactly what I was looking for!

I can send you a board if you like to play with it.

[klotzy_550]

Thanks, I appreciated the offer, but the circuit appears to be pretty straight forward so I would like to incorporate it onto a new revision board right away. From there it should just be a case of denial and error .

Again, I appreciate the offer!