Decoder BCD 4-bit to Seven Segment
Types of BCD decoder into seven segments there are two kinds namely: which decoder functions for driving seven segment common anode mode, and decoder that functions for driving seven segment common cathode mode. but in this post we only present the common cathode mode decoder using IC 74LS47. The 74LS47 is usually used to display data from counter IC which then displayed on the seven segments.
The IC 74LS47 Feature active-low outputs designed for driving common-anode seven segment leds. The Schematic diagram of the 74LS47 is used to control the seven segments in the show on the image below
- (BI’) must be hight “1” when output function 0 throuht 15 are desired. The (RBI’) must be hight “1” if blanking of decimal zero is not desired.
- When (BI’) low “0” all segment outputs are off regardless of the omy other input
- (RBI’) adn input (ABCD) are low “0” with the lamp test hight, all segment outputs go off
- (BI/RBO’) hight and a low is applied to the lamp-test input, all segment outputa are on