Description The SN74LS47 is a 7-segment Driver IC. It is used to drive a 7-segment display without the need of a microcontroller. It accepts decimal values (Binary coded) as inputs and provides a pattern on output pins that can display from 0 to 9 on a 7-segment display. The 74LS47 accepts four lines of BCD input data, generates their complements internally, and decodes the data with seven AND/OR gates having open-collector outputs to drive indicator segments directly. It can operate from 3V to 18V and can source up to 25mA on each output pin, which is high enough to illuminate the LEDs in a 7-segment display directly. PIN CONFIGURATION Pin no. Pin name Description 1,2,6,7 B,C,D,A BCD input of the IC 3 Display test/Lamp test To test the display LEDs 4 Blank input To turn-off the LEDs of the display 5 RBI (bar) Store or strobe a BCD code 8 Gnd Ground 9,10,11,12,13,14,15 e,d,c,b,a,g,f 7-segment outputs 16 Vcc Positive supply input
