(A LED emits light only when its forward bias is about 1.5 V.) The resistor in this circuit protects the LED and the NAND gate from drawing too much current. The logic diagram for a complete BCD-to- decimal decoder is given in Fig. 26-3 la.
|Title||:||Electric circuit analysis|
|Author||:||Charles A. Schuler, Richard J. Fowler, Jay D. Helsel|
|Publisher||:||Glencoe/McGraw-Hill Post Secondary - 1993|