74LS244

SN74LS244 replacement chip. DIP-20, Octal Buffers and Line Drivers With 3-State Outputs

The 74LS244 is an octal buffer/line driver with 3-state outputs, and it belongs to the 74LS family of integrated circuits. This family is part of the larger 7400 series, which consists of various digital logic ICs (integrated circuits) designed for different applications. The “74” in the name indicates that it is a standard TTL (Transistor-Transistor Logic) device.

Here are some key features and details about the 74LS244:

1. Functionality:
   • The 74LS244 is designed as an octal buffer, meaning it has eight separate buffer channels.
   • Each channel is capable of driving high or low logic levels and can be individually enabled or disabled.
   • The device is used to control the flow of data between two buses or systems.
2. 3-State Outputs:
   • The outputs of the 74LS244 are 3-state, which means they can be in one of three states: high, low, or high-impedance (disconnected).
   • The high-impedance state allows multiple devices to be connected to the same bus without causing conflicts.
3. Pin Configuration:
   • The IC comes in a 20-pin dual in-line package (DIP).
   • It has eight input pins (A1 to A8) and eight corresponding output pins (Y1 to Y8).
   • The device also features an active-low output enable pin (OE), which controls the 3-state outputs.
4. Voltage and Power:
   • The 74LS244 typically operates with a power supply voltage of 4.75 to 5.25 volts.
   • Power consumption is relatively low compared to more modern technologies.
5. Applications:
   • The 74LS244 is commonly used in digital systems for bus buffering, data line driving, and signal isolation.
   • It finds applications in various electronic devices and projects where multiple components need to communicate with each other.
6. Compatibility:
   • The 74LS244 is compatible with other TTL devices, making it easy to integrate into existing digital circuits that use TTL logic.

It’s important to note that the 74LS series, including the 74LS244, is an older technology. While it may still be used in some applications, more modern families of ICs like CMOS (Complementary Metal-Oxide-Semiconductor) and other advanced technologies are now prevalent in digital design due to their improved performance and lower power consumption.

Arcade Games and Pinball Machines that Use 74LS244

The following arcade games and pinball machines use the 74LS244 on their PCBs:

• 1943
• Asteroids
• Battlezone
• Bubble Bobble
• Donkey Kong
• Dragon’s Lair
• Gyruss
• Hard Drivin’
• Ice Cold Beer
• Major Havoc
• Missile Command
• Ms. Pac-Man
• NBA Jam
• Nibbler
• Pac-Man
• Pole Position
• Qix
• Red Baron
• Road Blasters
• Robotron
• Space Duel
• Superman
• Tempest
• Tron
• Wizard of Wor
• Zoo Keeper
• many others…

74LS244 / 74LS244N Pinout

The following represents the pinout of the 74LS244N in a DIP-20 package, commonly used in arcade and pinball machines.

• PIN 1:Channel 1 output enable
• PIN 2: Channel 1, A side 1
• PIN 3: Channel 2, Y side 4
• PIN 4: Channel 1, A side 2
• PIN 5: Channel 2, Y side 3
• PIN 6: Channel 1, A side 3
• PIN 7: Channel 2, Y side 2
• PIN 8: Channel 1, A side 4
• PIN 9:Channel 2, Y side 1
• PIN 10: Ground
• PIN 11: Channel 2, A side 1
• PIN 12: Channel 1, Y side 4
• PIN 13: Channel 2, A side 2
• PIN 14: Channel 1, Y side 3
• PIN 15: Channel 2, A side 3
• PIN 16: Channel 1,Y side 2
• PIN17: Channel 2, A side 4
• PIN 18: Channel 1, Y side 1
• PIN 19: Channel 2 output enable
• PIN 20: Vcc

74LS244 Datasheet

You can find the datasheet for the 74LS244 here: 74LS244 datasheet