SCES582I July   2004  – February 2025 SN74AVCH2T45

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configurations and Functions
  6. 5 Specifications
    1. 5.1  Absolute Maximum Ratings
    2. 5.2  ESD Ratings
    3. 5.3  Recommended Operating Conditions
    4. 5.4  Thermal Information
    5. 5.5  Electrical Characteristics
    6. 5.6  Switching Characteristics: VCCA = 1.2V
    7. 5.7  Switching Characteristics: VCCA = 1.5V
    8. 5.8  Switching Characteristics: VCCA = 1.8V
    9. 5.9  Switching Characteristics: VCCA = 2.5V
    10. 5.10 Switching Characteristics: VCCA = 3.3V
    11. 5.11 Operating Characteristics
    12. 5.12 Typical Characteristics
      1. 5.12.1 Typical Propagation Delay (A to B) vs Load Capacitance, TA = 25°C, VCCA = 1.8V
      2. 5.12.2 Typical Propagation Delay (A to B) vs Load Capacitance, TA = 25°C, VCCA = 2.5V
      3. 5.12.3 Typical Propagation Delay (A to B) vs Load Capacitance, TA = 25°C, VCCA = 3.3V
  7. 6 Parameter Measurement Information
    1. 6.1 23
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 VCC Isolation
      2. 7.3.2 2-Rail Design
      3. 7.3.3 IO Ports are 4.6 V Tolerant
      4. 7.3.4 Partial Power Down Mode
      5. 7.3.5 Bus Hold on Data Inputs
    4. 7.4 Device Functional Modes
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Unidirectional Logic Level-Shifting Application
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curve
      2. 8.2.2 Bidirectional Logic Level-Shifting Application
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
          1. 8.2.2.2.1 Enable Times
        3. 8.2.2.3 Application Curve
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Documentation Support
      1. 9.1.1 Related Documentation
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

3 Description

This 2-bit non-inverting bus transceiver uses two separate configurable power-supply rails. The A ports are designed to track VCCA and accepts any supply voltage from 1.2V to 3.6V. The B ports are designed to track VCCB and accepts any supply voltage from 1.2V to 3.6V. This allows for universal low-voltage bidirectional translation and level-shifting between any of the 1.2V, 1.5V, 1.8V, 2.5V, and 3.3V voltage nodes.

The SN74AVCH2T45 is designed for asynchronous communication between two data buses. The logic levels of the direction-control (DIR pin) input activate either the B-port outputs or the A-port outputs. The device transmits data from the A bus to the B bus when the B-port outputs are activated and from the B bus to the A bus when the A-port outputs are activated. The SN74AVCH2T45 features active bus-hold circuitry, which holds unused or un-driven inputs at a valid logic state. TI does not recommend using pull-up or pull-down resistors with the bus-hold circuitry.

This device is fully specified for partial-power-down applications using Ioff. The Ioff circuitry disables the outputs, preventing damaging current backflow through the device when it is powered down. The VCC isolation feature ensures that if either VCC input is at GND, then both outputs are in the high-impedance state. The bus-hold circuitry on the powered-up side always stays active.

Active bus-hold circuitry holds unused or un-driven inputs at a valid logic state. NanoFree package technology is a major breakthrough in IC packaging concepts, using the die as the package.

Package Information
PART NUMBER PACKAGE (1) PACKAGE SIZE (2)
SN74AVCH2T45 DCT (SSOP, 8) 2.95mm × 4.00mm
DCU (VSSOP, 8) 3.10mm × 2.00mm
YZP, (DSBGA, 8) 1.89mm × 0.89mm
(1) For more information, see Section 11
(2) The package size (length × width) is a nominal value and includes pins where applicable
SN74AVCH2T45 Logic Diagram (Positive Logic) Logic Diagram (Positive Logic)