I'm working on a project where I need to drive 3 big SSDs (3") over I2C
In order to do so, I'm using an Arduino Nano as the slave, that will extract each digit and drive the proper SSD.
My SSD are Common Anode. I already built a circuit behind each SSD, that receive a 5 V. signal, and drive a transistor to ground. That portion works fine . It uses some 2N2222
Where I'm having a problem, is when I need to drive each SSD in sequence. I did some test on a proto board: a 5 v. signal goes thru a 1K resistor to the base of a TIP32. The Collector is hooked to +12 V and the emitter to the Common Anode of my SSD. On the proto board, it works.
When hooked to the Arduino, all transistors are conducting and the 3 SSD gets the same signal.
Attached is the complete drawing, showing only one segment of my SSD, but the 3 SSD driver.
Anyone can tell me what is wrong, and what could be a working solution ?
In order to do so, I'm using an Arduino Nano as the slave, that will extract each digit and drive the proper SSD.
My SSD are Common Anode. I already built a circuit behind each SSD, that receive a 5 V. signal, and drive a transistor to ground. That portion works fine . It uses some 2N2222
Where I'm having a problem, is when I need to drive each SSD in sequence. I did some test on a proto board: a 5 v. signal goes thru a 1K resistor to the base of a TIP32. The Collector is hooked to +12 V and the emitter to the Common Anode of my SSD. On the proto board, it works.
When hooked to the Arduino, all transistors are conducting and the 3 SSD gets the same signal.
Attached is the complete drawing, showing only one segment of my SSD, but the 3 SSD driver.
Anyone can tell me what is wrong, and what could be a working solution ?