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

RF modulator
Ir Receiver I
Arduino Knock
h bridge circuit
Vibration Detector Circuit
Inductive Proximity Sensors
Most Accurate Clock
PGA202 offset voltage correction circuit
High-performance power supply LM334
Half-wave rectifier circuit principle