74LS20 Dual Four input NAND in Pakistan

The 74LS189 is a high-speed 64-bit RAM organized as a 16-word by the 4-bit array. Address inputs are buffered to minimize loading and are fully decoded on-chip. The outputs are 3-state and are in the high impedance state whenever the Chip Select (CS) input is HIGH. The outputs are active only in the read mode and the output data is the complement of the stored data.

The 74LS48 features active-high outputs for driving lamp buffers or common-cathode LEDs. They have full ripple-blanking input/output controls and a lamp test input. Display patterns for BCD input count above 9 are unique symbols to authenticate input conditions. Their circuits incorporate automatic leading and/or trailing-edge zero-blanking control (RBI\ and RBO\). Lamp test (LT\) of these types may be performed at any time when the BI\/RBO\ node is at a high level. They contain an overriding blanking input (BI\), which can be used to control the lamp intensity by pulsing or to inhibit the outputs. Inputs and outputs are entirely compatible for use with TTL logic outputs.

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.