Hello guys 
I would like to drive a 4" large 7-segments LED with my arduino nano.
This 7-segments is common anode
and 12V driven.
I have understood I have to use a Constant-Current LED Sink Driver
(sink and not source because of common anode).
I wish you could tell me what reference of driver I could buy in 2014?
as I have googled many threads but often the chip references are outdated... :~
(Allegro 6278EAT from this post on deleteaso.com)
Could you please tell me what I can buy?
Thanks
yours
Mat
PS : I know there is an alternative but I would like to not use 7 NPN transistors and 14 resistors to simplify the wiring.
edit : here is what I have done
thanks to PaulRB, CrossRoads, Grumpy_Mike, Paul__B !
-> job done with TPIC6C595
see in attachement PCB and wiring diagram
- arduino SPI library
Here is the result in video!
Thanks guys for the help so far!
/*
Shift Register Example for 74HC595 shift register by Tom Igoe
Digital Pot Control by Tom Igoe
Thanks to Heather Dewey-Hagborg for the original tutorial, 2005
Thanks to CrossRoads!
by RacingMat 09-2014
*/
// include the SPI library:
#include <SPI.h>
byte fontArray[] = {
// dp-a-b-c-d-e-f-g
0b11101110, // 0
0b00101000, // 1
0b11001101, // 2
0b01101101, // 3
0b00101011, // 4
0b01100111, // 5
0b11100111, // 6
0b00101100, // 7
0b11101111, // 8
0b01101111, // 9
0b00010000, // DP
};
//Pin connected to Data in SER IN pin 2 of 6c595
const int dataPin = 11;
//Pin connected to latch pin (SRCK)pin 15 of 6c595
const int latchPin = 13;
//Pin connected to clock pin (RCK) pin 10 of 6c595 as the slave select
const int slaveSelectPin = 10;
void setup() {
// set the Pins as output:
pinMode(dataPin, OUTPUT);
pinMode(latchPin, OUTPUT);
pinMode (slaveSelectPin, OUTPUT);
Serial.begin(9600);
// initialize SPI:
SPI.begin();
// take the SS pin low to select the chip:
digitalWrite(slaveSelectPin,LOW);
}
void loop() {
for (int i=0; i <= 10; i++){
delay(500);
digitalWrite (slaveSelectPin, LOW); // << RCLK line goes low
SPI.transfer (fontArray[i]); // << SRCLK goes high-low 8 times to output 8 bits of data
digitalWrite (slaveSelectPin, HIGH); // data outputs change on this rising edge << RCLK line goes high to move data into output register
}
}
edit :
Some news:
this video to demonstrate how Simtools can extract data from racing games in real time
it's really synchronized between GT Legends and the LDC display
Physically how will the digit to display be transmitted to the Arduino?
It is via a USB com port
There are two free softwares which can drive actuators for dynamic simulators and dashboard incidentally
-Simtools software
-xSim software with an example of more complex digital dashboard
