SN74LVCHR32245A

` Member of the Texas Instruments Widebus+™ ` Ioff Supports Partial-Power-Down Mode Family Operation
` Operates From 1.65 V to 3.6 V ` Supports Mixed-Mode Signal Operation on All Ports (5-V Input/Output Voltage With 3.3-V ` Inputs Accept Voltages to 5.5 V VCC)
` Max tpd of 4.8 ns at 3.3 V
` Other Products to Consider: SN74LVC32245, ` Input and Output Ports Have Equivalent 26-W SN74LVCH32245A, SN74LVCR32245A Series Resistors, So No External Resistors
` Latch-Up Performance Exceeds 250 mA Per Are Required JESD 17
` Typical VOLP (Output Ground Bounce) <0.8 V
` ESD Protection Exceeds JESD 22 at VCC = 3.3 V, TA = 25°C
  2000-V Human-Body Model (A114-A)
` Typical VOHV (Output VOH Undershoot) >2 V at VCC = 3.3 V, TA = 25°C
  200-V Machine Model (A115-A)
` Bus Hold on Data Inputs Eliminates the Need 1000-V Charged-Device Model (C101) for External Pullup/Pulldown Resistors

This 32-bit (quad-octal) noninverting bus transceiver SN74LVCHR32245A is designed for 1.65-V to 3.6-V V_CC operation.

The SN74LVCHR32245A is designed for asynchronous communication between data buses. The control-function implementation minimizes external timing requirements.

This device SN74LVCHR32245A can be used as four 8-bit transceivers, two 16-bit transceivers, or one 32-bit transceiver. It allows data transmission from the A bus to the B bus or from the B bus to the A bus, depending on the logic level at the direction-control (DIR) input. The output-enable (OE) input can be used to disable the device so that the buses
are effectively isolated.

The SN74LVCHR32245A data I/Os and control inputs are overvoltage tolerant. This feature allows the use of this device for down translation in a mixed-voltage environment.

The SN74LVCHR32245A outputs, which are designed to sink up to 12 mA, include equivalent 26-W resistors to reduce overshoot and undershoot.

This device SN74LVCHR32245A 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.

To ensure the high-impedance state during power up or power down, SN74LVCHR32245A OE should be tied to V_CC through a pullup resistor; the minimum value of the resistor is determined by the current-sinking capability of the driver.

Active bus-hold circuitry is provided to hold unused or floating data inputs at a valid logic level. Use of pullup or pulldown resistors with the bus-hold circuitry is not recommended. The bus-hold circuitry is part of the input circuit and is not disabled by OE or DIR.