ulm2803 connections

595, ulm2803 and uno for 8x8x8 rgb cube

i built cube with 3904’s and turned out to be a $#^@* job. the 2803’s seem to be an esier setup and a lot smaller board.

by googling, i am understanding i do not need the resistors ahead of array like the 3904’s, is this correct??

is my schematic looking correct for wiring

Hi, you don't need resistors between the 595 outputs and the 2803 inputs, if that's what you're asking. There are 2K7 built-in to the 2803 inputs.

I think the pin labelled CD+ (normally labelled COM) on the 2803 should go to 5V rather than ground.

A simpler design than this would be to use tpic6c595. This is a medium current shift register similar to the 74hc595 but with fet transistors on the outputs, so the 2803 would not be needed.

If only someone had already designed a board combining an Arduino and a bunch of tpic chips and would be willing to sell you one....

Paul

Connecting pin 10 to ground will turn on all the LEDs, similar to a lamp test.
Pin 10 is connected to + on the o/p power supply for relay coil snubbing.

You are using LEDs so pin 10 can be left open.

thanks for replies and hope everyone is having good holiday(s).

where i have my account to purchase supplies, it’s either a crap-load of 3904’s (200+) or 2803’s (25)
i like the idea of the 2803’s simply for easier wiring and smaller board IF the design will work the same way.

if understanding correctly,
i can omit the wiring to pin10 completely
i DO NOT need the resistor between 595 being the 2803 have the 2.7k already

i can omit the wiring to pin10 completely Yes if you are driving LEDs

i DO NOT need the resistor between 595 being the 2803 have the 2.7k already Yes

THANK YOU ;D

im excited now to get started.