SN74LVC4245APWR

Translators, Level Shifters Overview

The SN74LVC4245APWR is an octal bus transceiver and 3.3-V to 5-V shifter with three-state outputs manufactured by Texas Instruments. It belongs to the 74LVC logic series and operates within a VCCA supply range of 4.5 V to 5.5 V and a VCCB supply range of 2.7 V to 3.6 V. The device features eight bidirectional channels in a 24-pin TSSOP package. Key electrical parameters include a maximum propagation delay of 6.7 ns, output currents of -24 mA (high) and 24 mA (low), and a maximum power supply current of 80 uA. It supports an operating temperature range from -40°C to +85°C.

Translators, Level Shifters Feature Summary

• Provides bidirectional voltage level shifting between 3.3-V and 5-V buses
• Allows switching between all 3.3-V or all 5-V outputs without board re-layout
• Control circuitry is powered by VCCA for consistent input threshold referencing

Translators, Level Shifters Applications

• Asynchronous communication between data buses
• Mobile phones
• PDA applications

Translators, Level Shifters Procurement Notes

Verify the specific suffix 'PWR' indicates the tape-and-reel packaging format distinct from the 'PW' tube variant. Confirm that the VCCA and VCCB supply voltages match the target system requirements, as this component requires dual independent power supplies for its A and B ports. Ensure the design accounts for the specific pinout alignment compatible with standard 245 devices.

Translators, Level Shifters Selection Notes

Select this component when interfacing systems requiring simultaneous 3.3-V and 5-V operation on different bus segments. The LVC series offers low static power consumption suitable for battery-powered applications. Consider the 24-TSSOP package constraints regarding thermal dissipation and PCB space. Verify that the required direction control and output enable signals are compatible with the logic levels provided by the controlling microcontroller.

Translators, Level Shifters Part Context

This part is part of the SN74LVC4245A family, which includes variants such as SN74LVC4245APW and SN74LVC4245APWT. These devices share identical electrical characteristics but differ primarily in packaging formats, with 'PWR' denoting the reel-based distribution method. The family is designed to facilitate easy migration between 3.3-V and 5-V systems while maintaining backward compatibility with existing 245 pinouts.

Translators, Level Shifters Replacement Considerations

SN74LVC4245APW

Translators, Level Shifters FAQ

How does the SN74LVC4245APWR handle voltage translation?

It acts as an octal bus transceiver that translates data between a 3.3-V bus (VCCB) and a 5-V bus (VCCA) based on the DIR input signal.

What is the function of the VCCA supply pin?

VCCA powers the A port and the control circuitry, ensuring that input thresholds are referenced correctly to the higher voltage domain.