74HC08 Logic Gate

I apologize for the previous inaccuracy in the resource link for the 74HCT08 datasheet. Here’s a corrected response combining the information you requested:

The 7408 and 74HCT08 are functionally identical quad 2-input AND gate integrated circuits (ICs), but they belong to different logic families.

• Function: Both perform the AND logic operation on two input signals (A and B). A high output (typically 5V) only occurs when both inputs are high.

• Logic Family:

  • 7408: TTL (Transistor-Transistor Logic) – This is an older logic family known for its robustness but higher power consumption compared to CMOS.
  • 74HCT08: HCT (High-speed CMOS compatible TTL) – This logic family offers lower power consumption and good compatibility with TTL circuits.

• Other Characteristics:

  • Number of Gates: Quad (4 independent AND gates in a single package)
  • Input Count: 2 inputs per gate (A and B)
  • Wide Operating Voltage Range (specifics depend on datasheet)

Applications:

• Implementing complex logic functions with multiple AND gates.
• Data multiplication (logical AND) – ANDing two high signals produces a high output, useful for data selection or filtering.
• Building various digital circuits like adders, decoders, and data selectors.

Choosing Between 7408 and 74HCT08:

• Use 7408 in strictly TTL circuitry due to its direct compatibility.
• Use 74HCT08 for these advantages:
  • Lower power consumption compared to 7408
  • Better noise immunity
  • Compatibility with mixed-logic circuits (including CMOS)

Resources:

You can find the datasheets for both ICs online, containing detailed specifications, pinout information, and truth tables:

• 7408 Datasheet: FUTURLEC
• 74HCT08 Datasheet: Texas Instruments [invalid URL removed]