74LS157

74LS157/ 74LS157N replacement chip. DIP-16, Quadruple 2-line to 1-line data selectors/multiplexers The 74LS157 is a quad 2-input multiplexer chip, which is part of the 74LS series of TTL (Transistor-Transistor Logic) integrated circuits. It is commonly used in digital electronics and can be found in various applications such as data selectors, bus drivers, and other multiplexing tasks. Here are some key features and specifications of the 74LS157: Quad 2-Input Multiplexer: The chip contains four independent 2-input multiplexers. Each multiplexer has two data inputs (A and B), one select input (S), and one output (Y). Select Inputs (S): The select inputs determine which input (A or B) is connected to the output. Depending on the binary value applied to the select inputs, one of the inputs is chosen for each multiplexer. Output Enable (OE) Pin: The 74LS157 usually includes an output enable pin (OE) that, when activated, allows the selected data to pass through to the output. When the OE input is high, the outputs are in a high-impedance state, effectively disconnecting them. Standard TTL Compatibility: The 74LS series uses TTL technology, which operates with a power supply voltage in the range of 4.75 to 5.25 volts. It is important to note that this technology is older, and more modern logic families like CMOS (Complementary Metal-Oxide-Semiconductor) or advanced TTL versions (e.g., 74HC, 74HCT) might be preferred in contemporary digital designs. Pin Configuration: The 74LS157 is packaged in a 16-pin dual in-line package (DIP) with specific pins allocated for power supply, ground, input data lines, select lines, and output. It’s important to consult the datasheet for the specific manufacturer and variant of the 74LS157 that you are using, as there might be slight variations in features or pin configurations between different manufacturers. Additionally, newer and more power-efficient technologies may be preferred in modern digital designs, but the 74LS157 and similar chips are still used in educational settings and for specific applications. Arcade Games and Pinball Machines that use 74LS157 The following arcade games and pinball machines use the 74LS157: 1943 Asteroids Centipede Centuri Eagle Choplifter Donkey Kong Galaga Galaxian Hang-on Jr. Pac-Man Mad Planets Major Havoc Millepede Missile Command Moon Patrol Omega Race Outrun Punch Out Qix Rampage Space Invaders Tempest Up’n Down Zoo Keeper many others… 74LS157 / 74LS157N Pinout The following represents the pinout of the 74LS157N in a DIP-16 package, commonly used in arcade and pinball machines.   PIN 1: A/B Select PIN 2: A Input 1 PIN 3: A Input 2 PIN 4: A Output PIN 5: B Input 1 PIN 6: B Input 2 PIN 7: B Output PIN 8: Ground PIN 9: C Output PIN 10: C Input 2 PIN 11: C Input 1 PIN 12: D Output PIN 13: C Input 2 PIN 14: C Input 1 PIN 15: Strobe PIN 16: Vcc 74LS157 Datasheet You can find the datasheet for the 74LS157 here: 74LS157 datasheet