cheaper charge pump Intersil 7660s an option?

[chromesphere]

Hey,
I recently had an incident with a signal generator.  Long story short, the charge pump in it blew.  May not have been the fault of the chip though.  The seller listed the signal generator as having 9-12v supply voltage.  12v is the max of the charge pump, so using a 12v powerpack was probably pushing it.  IMO the seller is an idiot for quoting the specs on the supply voltage of the signal generator.  Charge pumps dont like overvoltage...

Anyway, I replaced it with a TC1044.  But i had a look on ebay for some 7660S charge pumps which look like a pin to pin compat with the others (max, lt, tc etc).  This listing has them, 5 for about 3 dollars!  That's pretty dam cheap for a charge pump.  Is there any reason not to use them?  They have the boost pin as well...I cant think of a reason why not to use them...the LT1054 is 2.50 per unit and the TC is even more expensive.  Maybe their fake!?

Heres the listing: http://www.ebay.com.au/itm/5p-ICL7660S-ICL7660SCPA-ICL7660SCPAZ-DIP8-IC-A171-/260823468782?pt=LH_DefaultDomain_0&hash=item3cba4a4aee

Your thoughts?
Paul

[MartyMart]

Hi Paul,

IIRC the 7660's are a little more robust than the 1044 ( which can only supply max 40Ma ? )

I would use those all the time and just avoid the 1044's

Be aware that there are lots of "fakes" on Ebay these days, in particular when it looks "too cheap" !  :-)

Marty.

[chromesphere]

Been looking at more sources, it seems the 7660 is substantially cheaper...I just wonder why...maybe its unreliable like the max1044 which imo, is crippled but its fragility.  Probably going to be only one way to find out!
Paul

[samhay]

I've used L7660SCPA - note the 'S' - for a couple of typical builds without issue. It works and the boost gets any noise out of the audio band. I haven't tried really loading them down with a high-current application.
I started using them because they are cheaper and easier  to find (in the UK) than the other usual suspects. I should probably mention that I get mine from a slightly more reputable source (Doctor Tweek) than ebay.