RGB clock

RGB clock

This is the documentation page for the RGB clock kit.

Overview

Driver PCB for up to 64 common-anode RGB LEDs, or 192 normal LEDs. The PCB is designed for 1:3 multiplexing of the LEDs, and is equipped with 8 74HC595 shift registers (configured as 4 16-bit deep registers), 64 current-limiting resistors (220 Ohm by default) and 3 FETs to switch the cathode groups on-and-off. The PCB is equipped with a bitwizard-standard 20-pin IO connector, designed to work together with our USB-multio PCB, but it is also possible to connect our FTDI-ATmega, USB-bigmultio or Cyclone dev board, or one of your own boards.

Assembling the kit

Component   Value
IC1-IC8     74HC595
R1-R64      220R
R65-R68     10K
R69-R74     1K
C1-C8       100nF
C9          10uF
T1-T3       N-channel FET
D1          Double Diode (BAT54S for example)
D2-D7       LED
SW1-SW4     Pushbutton

External resources

http://www.fairchildsemi.com/ds/MM/MM74HC595.pdf

Pinout

SV10 is connected as follows

1	GND
2	GND
3	SER0
4	SER1
5	SER2
6	SER3
7	!OE
8	LATCH
9	!RESET
10	CLOCK
11	R
12	G
13	B
14	external clock source
15	IO1
16	IO0
17	IO3
18	IO2
19	VCC
20	VCC

SV1 through SV8 are connected as follows:

1	A0
2	A1
3	A2
4	A3
5	A4
6	A5
7	A6
8	A7
9	R
10	G
11	B
12	GND

SV9 can be used to connect an external clock source, or a servo motor, or...

1	GND
2	VCC
3	connected to pin14 form SV10

• D2 is connected to VCC from SV10
• D3 is connected to USB power
• D4 is connected to pin17 from SV10
• D5 is connected to pin18 from SV10
• D6 is connected to pin15 from SV10
• D7 is connected to pin16 from SV10

• Switch1 (next to R71) is connected to pin16 from SV10
• Switch2 (next to R72) is connected to pin15 from SV10
• Switch3 (next to R73) is connected to pin18 from SV10
• Switch4 (next to R74) is connected to pin17 from SV10

Jumper settings

JP1: Power supply selection. Open: LED driver board and microcontroller board have individual powersupplies Closed: VCC from LED driver board and microcontroller board are connected.

Future hardware enhancements

• Replace 2 12-pin connectors by 1 20-pin connector
• Add numbers to the pushbutton switches

Changelog

1.0

• Initial public release