Infrared transmitter II


Posted on Jul 27, 2012

The transmitter keyboard is arranged as a scanned matrix. The matrix consists of 7 driver outputs and 7 sense inputs. The driver outputs DRVON to DRV6N are open-drain n-channel transistors and they are conductive in the stand-by mode. The 7 sense inputs (SENON to SEN6N) enable the generation of 56 command codes. With 2 external diodes all 64 commands are addressable.


Infrared transmitter II
Click here to download the full size of the above Circuit.

The sense inputs have p-channel pull-up transistors, so that they are HIGH until they are pulled LOW by connecting them to an output via a key depression to initiate a code transmission.




Leave Comment

characters left:

New Circuits

.

 


Popular Circuits

Auto Loudness Control
Leach amplifier
8 way electronic selector / switch
555 Based Alarm Circuit
GPZ spike Detector
NTSC Video Using the 68HC908QY4
ATmega8 breadboard circuit Tutorial
Water Level Detector With Alarm
High-billion food disinfection cabinet circuit
Using ASCII keyboard code development system
Asia ultrasonic remote control fan speed control circuit diagram



Top