Looking for best practices here. I'm building a common-anode LED matrix. I've got a current sink LED driver, and I'm looking for a latch that will provide enough current to drive an array of LEDs. All the latches I can find have very low current ratings. This guy had some success with running high current latches in parallel to provide the current, but it seems sloppy and is definitely expensive. I am leaning towards trying a low current latch with a Darlington array, however I've never used one before and don't know what exactly I'm looking for. Can anyone tell me if that's a good way to go about it, and suggest an 8 bit latch and Darlington array combo? Thanks.

  • \$\begingroup\$ When you say "latch", are you talking about a digital latch such as D-latch, RS-latch, etc? Or something else entirely? \$\endgroup\$ – The Photon Aug 19 '15 at 22:54
  • \$\begingroup\$ I'm sorry I was unclear. I meant a latched source driver. \$\endgroup\$ – Riley McCullagh Aug 19 '15 at 22:56
  • \$\begingroup\$ How much current do you need per LED? (20 mA or 20 A or somewhere in between?) \$\endgroup\$ – The Photon Aug 19 '15 at 23:01
  • \$\begingroup\$ Not sure at this stage, the LED matrices i bought haven't arrived yet and they did not have a data sheet. Let's assume 20mA per LED, and 32 columns, around 0.64 A at any one time, with only one channel open at a time (walking bit). \$\endgroup\$ – Riley McCullagh Aug 19 '15 at 23:44
  • \$\begingroup\$ so you mean a shift register with latched outputs, which can source/sink a large amount of current? \$\endgroup\$ – KyranF Aug 20 '15 at 0:04

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