74AC08B

Overview

The STMicroelectronics 74AC08B is a quad 2-input AND gate fabricated using sub-micron silicon gate and double-layer metal wiring C2MOS technology. It operates within a supply voltage range of 2V to 6V. The device features high-speed performance with a typical propagation delay of 4ns at VCC = 5V, low power dissipation with a maximum quiescent current of 2μA at 25°C, and high noise immunity where VNIH and VNIL are minimum 28% of VCC. It provides symmetrical output impedance with |IOH| and IOL minimums of 24mA, balanced propagation delays (tPLH ≈ tPHL), and 50Ω transmission line driving capability.

Feature Summary

• Advanced high-speed CMOS fabrication utilizing sub-micron silicon gate and double-layer metal wiring C2MOS technology for enhanced performance.
• Integrated protection circuits on all inputs and outputs providing static discharge immunity against transient excess voltage.
• Internal circuit design composed of two stages including buffer output to ensure high noise immunity and stable signal output.

Applications

• Digital logic systems requiring quad 2-input AND functionality
• Transmission lines with impedances as low as 50 ohms
• General-purpose digital applications compatible with standard 74 series 08 pinouts

Procurement Notes

Verify the specific package type required, as the 74AC08B designation corresponds to the Plastic DIP-14 package according to the datasheet ordering codes. Confirm that the application environment remains within the recommended operating conditions, specifically the supply voltage range of 2V to 6V and the operating temperature range of -55°C to 125°C. Ensure input rise and fall times adhere to the specified limits relative to the supply voltage to maintain guaranteed AC electrical characteristics.

Selection Notes

Select this component when a quad 2-input AND gate is needed with high-speed switching capabilities and low power consumption. It is suitable for designs requiring compatibility with existing 74 series 08 layouts while benefiting from improved latch-up immunity and higher drive strength compared to older technologies. Consider the 50Ω transmission line driving capability if interfacing with such lines.

Part Context

The 74AC08 belongs to the 74AC family of advanced CMOS logic devices produced by STMicroelectronics. This family offers superior speed and power efficiency over standard 74LS or 74HC counterparts. The 74AC08 specifically integrates four independent AND gates into a single package, serving as a fundamental building block for complex digital logic circuits requiring multiple logical conjunction operations.

Replacement Considerations

The datasheet notes pin and function compatibility with the 74 series 08. Verify that any substitute maintains the same 14-pin configuration and logical truth table. Ensure the replacement device supports the required 2V to 6V operating voltage range and meets the necessary propagation delay specifications for the target application speed.