Memória 3
Codificadores
y Descodificadores.
Estudio del codificador 74148
Salidas Entradas Salida
Vcc Eo Gs D3 D2 D1 D0 A0
D4 D5 D6 D7 E1 A2 A1
Entradas Salidas
E1 = inivición
E1 = 0 no fuinciona
E0 = 0 entrada a nivel 4
Gs = 0 algun nivel esta 0
Simbolo Lógico
Tabla de la verdad
| ENTRADAS | SALIDAS |
| E1 | D0 | D1 | D2 | D3 | D4 | D5 | D6 | D7 | A2 | A1 | A0 | GS | EO |
| 1 | X | X | X | X | X | X | X | X | 1 | 1 | 1 | 1 | 1 |
| 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 |
| 0 | X | X | X | X | X | X | X | 0 | 0 | 0 | 0 | 0 | 1 |
| 0 | X | X | X | X | X | X | 0 | 1 | 0 | 0 | 1 | 0 | 1 |
| 0 | X | X | X | X | X | 0 | 1 | 1 | 0 | 1 | 0 | 0 | 1 |
| 0 | X | X | X | X | 0 | 1 | 1 | 1 | 0 | 1 | 1 | 0 | 1 |
| 0 | X | X | X | 0 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 1 |
| 0 | X | X | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 0 | 1 |
| 0 | X | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 1 |
| 0 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 |
Estudio del decodificador 7442
Entradas Salidas
Vcc A B C D 9 8 7
0 1 2 3 4 5 6
Salidas
Simbolo Lógico
Tabla de la verdad
| ENTRADAS | SALIDAS |
| D | C | B | A | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |
| 0 | 0 | 0 | 0 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| 0 | 0 | 0 | 1 | 0 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| 0 | 0 | 1 | 0 | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| 0 | 0 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 |
| 0 | 1 | 0 | 0 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 |
| 0 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 1 |
| 0 | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 1 |
| 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 |
| 1 | 0 | 0 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 |
| 1 | 0 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 |
| 1 | 0 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| 1 | 1 | 0 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| 1 | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
Estudio del descodificador 7448, BCD, con 7 segmentos
Vcc F G A B C D E
B C LT bi/rbo RBI D A
RBI ( Pipple Bolcking Input)
RBI = 0 no se vizualiza
RBI = 1 si se vizualiza
BI = 0 desactiva todos los segmentos del display
BI = 1 Normal
Simbolo lógico
Tabla de la verdad
| Decimal | ENTRADAS | SALIDAS |
| | LT | RBI | D | C | B | A | A | B | C | D | E | F | G |
| 0 | 1 | 1 | 0 | 0 | 0 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 0 |
| 1 | 1 | X | 0 | 0 | 0 | 1 | 0 | 1 | 1 | 0 | 0 | 0 | 0 |
| 2 | 1 | X | 0 | 0 | 1 | 0 | 1 | 1 | 0 | 1 | 1 | 0 | 1 |
| 3 | 1 | X | 0 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 1 |
| 4 | 1 | X | 0 | 1 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 1 | 1 |
| 5 | 1 | X | 0 | 1 | 0 | 1 | 1 | 0 | 1 | 1 | 0 | 1 | 1 |
| 6 | 1 | X | 0 | 1 | 1 | 0 | 0 | 0 | 1 | 1 | 1 | 1 | 1 |
| 7 | 1 | X | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 |
| 8 | 1 | X | 1 | 0 | 0 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| 9 | 1 | X | 1 | 0 | 0 | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 1 |
| 10 | 1 | X | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 1 | 1 | 0 | 1 |
| 11 | 1 | X | 1 | 0 | 1 | 1 | 0 | 0 | 1 | 1 | 0 | 0 | 1 |
| 12 | 1 | X | 1 | 1 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 1 | 1 |
| 13 | 1 | X | 1 | 1 | 0 | 1 | 1 | 0 | 0 | 1 | 0 | 1 | 1 |
| 14 | 1 | X | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 1 | 1 | 1 | 1 |
| 15 | 1 | X | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| BI | X | X | X | X | X | X | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| RBI | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| LT | 0 | X | X | X | X | X | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
D C B A D C B A D C B A D C B A
Display de 7 segmentos
a
b
f
g
e c
d
Si hay + - no pasará la corriente
Cuando hay un 1
A
B
C
......
Cuando hay un 0
A
B
C
Codificadores y Descodificadores
Codificadores y Descodificadores
Codificadores y Descodificadores
