74LS02 74AHS02 7402 Quad 2-input NOR gate in Pakistan

74HC85 4-Bit Comparator IC (7485 IC) DIP-16 Package. 74LS85 is the four-bit magnitude comparators that perform a comparison of straight binary and straight BCD (8-4-2-1) codes. Three fully decoded decisions about two 4-bit words (A, B) are made and are externally available at three outputs. These devices are fully expandable to any number of bits without external gates.

74HC157 is a high-speed multiplexer integrated circuit consisting of four 2-input digital multiplexers inside the chip. It is pin-compatible with Low-power Schottky TTL. It has two control inputs namely enable and select input. Additionally, it has two groups of registers. The selected input determines the register from which the data comes. Its operation is specified over a temperature range of -55 °C to 125 °C.

These full adders perform the addition of two 4-bit binary
numbers. The sum (R) outputs are provided for each bit and
the resultant carry (C4) is obtained from the fourth bit.
These adders feature a full internal look ahead across all four
bits. This provides the system designer with a partial lookahead
performance at the economy and reduced package
count of a ripple-carry implementation.