SN74AHCT373PW

Overview

The SN74AHCT373PW is an octal transparent D-type latch with 3-state outputs manufactured by Texas Instruments. It operates within a supply voltage range of 4.5V to 5.5V and features TTL-compatible inputs. The device provides balanced CMOS outputs capable of sourcing and sinking 8mA. Propagation delay is typically 9.5ns at 5V with a 15pF load. It is housed in a 20-pin TSSOP package and supports an operating temperature range from -40°C to +85°C.

Feature Summary

• Contains eight D-type latches sharing common latch enable (LE) and output enable (OE) control lines.
• Features balanced CMOS 3-state outputs that can actively drive high, low, or enter a high-impedance state.
• Includes TTL-compatible CMOS inputs designed for direct interfacing with standard logic devices.

Applications

• Parallel data storage
• Digital bus buffer

Procurement Notes

Verify the specific ordering suffix 'PW' corresponds to the 20-pin TSSOP package configuration required for your PCB layout. Confirm that the application environment remains within the specified 4.5V to 5.5V supply voltage limits and the -40°C to +85°C operating temperature range to ensure reliable operation.

Selection Notes

Select this component when an octal latch with 3-state capability is needed for 5V logic systems. Ensure the design accommodates the TTL-compatible input thresholds and the specific propagation delays associated with the AHCT series. Verify that the TSSOP-20 footprint matches the available board space and thermal requirements.

Part Context

This part belongs to the SNx4AHCT373 family of octal transparent D-type latches. The 'SN74' prefix indicates commercial grade performance, while 'AHCT' denotes advanced high-speed CMOS technology with TTL-compatible inputs. The 'PW' suffix specifically identifies the plastic small-outline package variant.

Replacement Considerations

Direct substitutes include other SN74AHCT373 variants with different packages such as DW (SOIC), DB (SSOP), or N (PDIP). Cross-vendor equivalents like Nexperia 74AHC373 may require verification of pinout compatibility and electrical parameter alignment.

FAQ

How do the LE and OE pins function?

The Latch Enable (LE) pin controls data transparency; when high, data passes from D to Q. The Output Enable (OE) pin controls the output state; when low, outputs are active, and when high, they enter a high-impedance state.

What happens if unused inputs are left floating?

Unused inputs must be terminated to VCC or GND. Leaving them floating can cause excessive power consumption, oscillations, and reduced device reliability due to the high impedance nature of CMOS inputs.