SN74AHCT373DW

Overview

The SN74AHCT373DW is an octal transparent D-type latch with three-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 up to 8mA. Propagation delay is specified at 9.5ns maximum at 5V VCC with a 15pF load. It utilizes a 20-pin SOIC package.

Feature Summary

• Contains eight D-type latches sharing common latch enable (LE) and output enable (OE) control lines.
• Features balanced CMOS three-state outputs for driving high, low, or high-impedance states.
• Includes TTL-compatible CMOS inputs designed to interface directly with TTL logic devices.

Applications

• Parallel data storage
• Digital bus buffer

Procurement Notes

Verify the specific ordering suffix 'DW' corresponds to the SOIC-20 package configuration required for your design. Confirm that the component meets RoHS compliance standards if applicable to your manufacturing process. Ensure the datasheet version matches the revision date to validate all electrical characteristics and timing parameters before finalizing procurement specifications.

Selection Notes

Select this component when a system requires an octal latch with three-state capability and TTL input compatibility. It is suitable for designs operating strictly within the 4.5V to 5.5V supply range. Consider the SOIC-20 package dimensions and thermal resistance values during PCB layout planning to ensure adequate heat dissipation and trace routing space.

Part Context

This part belongs to the SNx4AHCT373 family of octal transparent D-type latches. The 'HCT' designation indicates High-speed CMOS technology with TTL-compatible input levels. The 'SN74' prefix denotes commercial grade temperature operation, while the 'DW' suffix specifies the surface-mount SOIC package type offered by Texas Instruments.

Replacement Considerations

Direct substitutes include other SN74AHCT373 variants in different packages such as TSSOP (PW), SSOP (DB), or PDIP (N). Cross-family replacements like SN74HC373 or SN74HCT373 may be considered but require verification of speed and drive current differences against application requirements.

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. When low, the previous state is held. The Output Enable (OE) pin, active low, controls whether the outputs are driven or placed in a high-impedance state.

What happens to unused inputs?

Unused inputs must not be left floating. They should be terminated to either VCC or GND to prevent excessive power consumption and oscillations caused by slow transitions or noise.