Tech Trill

                                                     




A digital family is a group of compatible devices with the same logic levels and supply voltages.The word compatible means that you connect the output of one device to the input of another device.
A digital family may be divided into two groups:

1)Bipolar Families:- These families include IC's with bipolar techonology.The bipolar category consists of the following  families
   a)Resistance transistor logic (RTL)
   b)Diode transistor logic (DTL)
   c)Transistor transistor logic (TTL)
   d)Emittor coupled logic (ECL)
   e)Integrated injuction logic (IIL)etc.
2)MOS families:- These families include IC's with MOS techonology.The MOS category consists of the following logic families
   a)P-channel MOSFET's (PMOS)
   b)N-channel MOSFET's (NMOS)
   c)Complementary MOSFET's (CMOS)

Different versions of TTL are:-
1)Low power TTL(54L / 74L series)
2)High power TTL(54H / 74H series)
3)Schottky TTL(54S / 74S series)
4)Low power schottky TTL(54LS / 74LS series)
5)Advanced schottky TTL and Advanced low power schottky TTL(54AS / 74ALS)

Different versions of CMOS are:-
1)4000series CMOS
2)74series HC(High speed)
3)74series HCT(High speed CMOS TTL compatible)
4)VHC(Very high speed CMOS)
5)VHCT(Very high speed CMOS TTL compatible)
6)FCT(Fast CMOS TTL compatible)