State-of-the-Art BiCMOS Design
Significantly Reduces ICCZ
Bus Transceivers/Registers
Independent Registers and Enables for
A and B Buses
Multiplexed Real-Time and Stored Data
ESD Protection Exceeds JESD 22
− 2000-V Human-Body Model (A114-A)
− 200-V Machine Model (A115-A)

description/ordering information
These devices consist of bus transceiver circuits, D-type flip-flops, and control circuitry arranged for multiplexed
transmission of data directly from the input bus or from the internal registers. Data on the A or B bus is clocked
into the registers on the low-to-high transition of the appropriate clock (CLKAB or CLKBA) input. Figure 1
illustrates the four fundamental bus-management functions that can be performed with the ’BCT646 devices.
Output-enable (OE) and direction-control (DIR) inputs are provided to control the transceiver functions. In the
transceiver mode, data present at the high-impedance port can be stored in either register or in both.
The select-control (SAB and SBA) inputs can multiplex stored and real-time (transparent mode) data. The
direction control (DIR) determines which bus will receive data when OE is low. In the isolation mode (OE high),
A data can be stored in one register and/or B data can be stored in the other register.