TC74HC244AF(EL,F)

Overview

The TC74HC244AF(EL,F) is an octal bus buffer featuring non-inverted, 3-state outputs fabricated with silicon gate C2MOS technology. It operates within a supply voltage range of 2 to 6 V and supports an operating temperature from -40°C to +85°C. The device provides symmetrical output impedance with a minimum drive capability of 6 mA for both high and low states. Typical propagation delay is 10 ns at 5 V, while maximum quiescent current is 4 μA. It includes input protection circuits against static discharge.

Feature Summary

• Features two active-low output enables for controlling the three-state logic levels.
• Provides high noise immunity with defined thresholds relative to the supply voltage.
• Maintains balanced propagation delays between low-to-high and high-to-low transitions.

Applications

• Used as memory address drivers in digital systems.
• Functions as a bus driver for data transmission lines.
• Serves as an interface buffer between different logic families.

Procurement Notes

Verify the specific package variant required, as the AF suffix indicates surface-mount packaging (typically SOP-20). Confirm RoHS compliance status through official Toshiba documentation or authorized distributors prior to ordering. Ensure the design accounts for the specified derating factors if operating temperatures exceed standard ranges. Validate that the application does not fall under unintended use restrictions defined by the manufacturer.

Selection Notes

Select this component when an octal buffer with non-inverting logic and dual active-low enable controls is required. It is suitable for designs needing CMOS low power dissipation combined with LSTTL-compatible speed and drive capabilities. Consider the 2 to 6 V operating range for compatibility with various system voltages. Ensure the load capacitance requirements align with the specified AC characteristics for the target frequency.

Part Context

This part belongs to the TC74HC240/241/244 family of octal bus buffers. While functionally similar to the HC series, the AF suffix specifically denotes the surface-mount package configuration. It differs from the TC74HC241A primarily in its enable pin configuration, utilizing two active-low enables rather than one active-high and one active-low.

Replacement Considerations

The TC74HC244AP is the pin-compatible DIP version of this device. Other members of the 74HC24x family may serve as functional alternatives depending on the specific enable logic requirements and package constraints of the target design.

FAQ

How many output enable pins does the TC74HC244AF have?

It features two active-low output enable pins.

What is the typical propagation delay at 5V?

The typical propagation delay is 10 ns when the supply voltage is 5 V.