TC74LCX573FK(EL,K)

Overview

The TC74LCX573FK(EL,K) is a low-voltage octal D-type latch manufactured by Toshiba Semiconductor and Storage. It operates within a supply voltage range of 1.65 V to 3.6 V, with specific data retention support down to 1.5 V. The device features 5-V tolerant inputs and outputs, allowing interface with 5-V environments. Propagation delay (D-Q) is 8.0 ns maximum at 3.0–3.6 V. Output drive current reaches 24 mA minimum at 3.0 V. Quiescent supply current is 10 µA maximum. Input leakage current is ±5 µA. Operating temperature spans -40 °C to 85 °C.

Feature Summary

• Provides power-down protection on all inputs and outputs to prevent excessive current draw during power-off states.
• Features 5-V tolerant I/Os, enabling direct interfacing between 3.3-V logic systems and 5-V supply environments.
• Offers pin and function compatibility with standard 74 series devices, including AC, VHC, HC, F, ALS, and LS types.

Applications

• Data storage in 3.3-V digital systems
• Interfacing low-voltage logic with 5-V tolerant buses
• Octal latch applications requiring high-speed operation

Procurement Notes

Verify the specific package variant required, as the FK suffix denotes VSSOP packaging while F denotes SOP. Confirm manufacturing date codes if 1.8 V operation is critical, as electrical characteristics for this voltage apply only to units produced from January 2009 onward. Ensure compliance with RoHS directives and check for any export control classifications relevant to the destination region before finalizing orders.

Selection Notes

Select this component when an octal latch with 5-V tolerance is needed for 3.3-V systems. It is suitable for designs requiring CMOS low power dissipation alongside high-speed performance. Consider the VSSOP package for space-constrained surface-mount applications. Verify that the input rise/fall times remain within the specified 10 ns/V limit to ensure proper timing margins.

Part Context

This part belongs to the TC74LCX series of low-voltage CMOS logic devices. It functions as an octal D-type latch, distinct from flip-flops by its level-sensitive latch enable mechanism rather than edge-triggered clocking. The device is designed for general-purpose digital logic applications where data latching and bus isolation are required.

Replacement Considerations

Direct substitutes include the TC74LCX573F (SOP package). Other compatible parts within the 74LCX family may offer similar functionality but require verification of package dimensions and exact electrical parameters against the datasheet specifications.

FAQ

Does the TC74LCX573FK support 1.8 V operation?

Yes, but the specific electrical characteristics for VCC = 1.8 ± 0.15 V apply only to products manufactured from January 2009 onward.

How does the latch enable input affect the outputs?

When the LE input is high, the outputs follow the D inputs. When LE goes low, the Q outputs are latched at the value present at the D inputs at that moment.

What happens when the output enable input is high?

When the OE input is high, the eight outputs enter a high-impedance state, effectively disconnecting them from the circuit.