Registered Bus Exchanger 1-Element 56-Pin SSOP T/R

This 12-bit to 24-bit registered bus exchanger is designed for 1.65-V to 3.6-V VCC operation. The SN74ALVCHR16269A is used in applications in which two ports must be multiplexed onto, or demultiplexed from, a single port. It is particularly suitable as an interface between synchronous DRAMs and high-speed microprocessors. Data is stored in the internal B-port registers on the low-to-high transition of the clock (CLK) input, when the appropriate clock-enable (CLKENA\) inputs are low. Proper control of these inputs allows two sequential 12-bit words to be presented as a 24-bit word on the B port. For data transfer in the B-to-A direction, a single storage register is provided. The select (SEL\) line selects 1B or 2B data for the A outputs. The register on the A output permits the fastest possible data transfer, thus extending the period during which the data is valid on the bus. The control terminals are registered so that all transactions are synchronous with CLK. Data flow is controlled by the active-low output enables (OEA\, OEB1\, and OEB2\).

• Member of the Texas Instruments Widebus™ Family
• Operates From 1.65 V to 3.6 V
• Max tpd of 5.2 ns at 3.3 V
• ±24-mA Output Drive at 3.3 V
• All Outputs Have Equivalent 26-? Series Resistors, So No External Resistors Are Required
• Bus Hold on Data Inputs Eliminates the Need for External Pullup/Pulldown Resistors
• Latch-Up Performance Exceeds 250 mA Per JESD 17
• ESD Protection Exceeds JESD 22
  • 2000-V Human-Body Model (A114-A)
  • 200-V Machine Model (A115-A)