7426 Quad Two input NAND, High voltage in Pakistan

The 74LS138 is a 3:8 Decoder IC that is commonly used in decoding or de-multiplexing circuits for memory decoding or data routing purposes. It is designed for high-speed operations and has three enable pins to make it easier to cascade with other ICs. The device decodes 1-of-8 lines, set by x3 binary select inputs & three enable inputs. The LS138 can be used as an 8- output demultiplexer by using one active LOW Enable input as data input & the other Enable inputs as strobes. The IC has an operating voltage from 1.0V to 5.5V with a low power consumption of 32mW. The propagation delay is around 21nS.

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.

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.