At 04:34 PM 11/2/2005 -0700, you wrote:
>Spehro Pefhany wrote:
>
>>At 12:29 PM 11/2/2005 -0700, you wrote:
>>
>>>Peter wrote:
>>>
>>>>I prefer CD4094 + CD4021 for this sort of application. Voltage range is 
>>>>3 to 15V ;-) It's only the good stuff they don't make anymore (or so 
>>>>they say - I think that these chips will be around forever).
>>>>
>>>>Peter
>>>
>>>I like the LV595 if below 5V and HC595 if 5V. The advantage is that these
>>>chips are VERY gutsy, can deliver 25mA ea at either rail all day long.
>>>
>>>--Bob
>>
>>
>>Yes, abs. max. is 35mA on the Qn outputs, but it's pretty easy to exceed
>>the maximum Icc or Ignd rating of 70mA. 8-(
>Rarely are more than one or two outputs driving that hard at the same 
>time, unless
>you are driving LED arrays. I've never run into a problem with 
>overheating. Most of
>my designs have one or two external 25mA source/sinks, then the rest of 
>the device
>is simple logic controls.
>
>--Bob

Bob, I'm worried about more subtle failure modes such as metal migration. I
agree that overheating is not an issue. And LED arrays is something I deal
with frequently.

Best regards,

Spehro Pefhany --"it's the network..."            "The Journey is the reward"
speff@interlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com
->> Inexpensive test equipment & parts http://search.ebay.com/_W0QQsassZspeff


-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist