Shift Registers and Darlington Arrays...

I am going to buy a few parts and I was wondering what the best shift registers are and what the best Darlington transistor arrays are. I think the best and most common is a 74HC595 for a Shift Register but I was wondering what kind of darlington is the best. I am going to buy these parts from Jameo Robotstore so my choices will be limited to the ICs there. :slight_smile:

Heres the shift register link:
http://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?jameco_page=46&langId=-1&productId=46105&drill_parents=category_root%24%2410%24%241042&drill_children=10%24%241042%24%24104245&catalogId=10001&storeId=10001&search_type=all&drill_displays=ICs+%26+Semiconductors+%2F+Logic%2C+CMOS+%2F+74HC+Series&ddkey=http:ParametricSearchResultsView

Heres the Darlington Transistor Array page, I am not sure which one is the bestโ€ฆ :
http://www.jameco.com/webapp/wcs/stores/servlet/ParametricSearchResultsView?langId=-1&storeId=10001&catalogId=10001&jameco_page=46&drill_parents=category_root%24%2410%24%241070&drill_children=10%24%241070%24%24107042&drill_displays=ICs%20%26%20Semiconductors%20%2F%20Transistors%20%2F%20Transistor%20Arrays
Thanks ;D

What is best depends on what your application and capabilites are. The 74*595 is as good choice for the shift register because there's existing driver code for it and lots of people here use it. Which logic family you use and whether or not you should consider another one depends on what you want to do with them.

And 'which Darlington array is best' is a question that depends ENTIRELY on what you're doing with them. So please tell us a bit about your application -- what kind of thing you're trying to drive, what kind of transistor base drive you have available, how fast you plan on switching, all the goodies.

Hmmm I kind of just wanted some Darlington arrays for jus general use in case i ever needed (I hear they have all sorts of useful applications) them but I dont think I was specific enough :) Ummm I probably wouldnt be driving motors with them but anywhere from 50ma+ @5-9V would be great I'm not sure how much these ones can supply... thnx!

I'm not sure how much these ones can supply

Generally 500mA per channel but not all channels can supply that at the same time. You are limited to about 650mA total. That is when you add them all up. See:- http://www.thebox.myzen.co.uk/Tutorial/Power_Examples.html

It's best to buy some of the darlington arrays that have 8 in/outs.

That way you can match one shift register with one array IC.

That could be for instance the ULN28XX series

The ULN20XX only has seven darlington pairs.

If you want a bit more current capacity, the ULN2067B is rated to 1.5 Amps:

http://www.st.com/stonline/products/literature/ds/1535/uln2075b.htm

But there's only four of them in a package.

f you want a bit more current capacity, the ULN2067B is rated to 1.5 Amps:

Yes but the power dissipation will limit this to a total of 714mA for any package at any one time.