SCBS264 - MARCH 1993
Widebus and UBT are trademarks of Texas Instruments Incorporated.
This 17-bit registered bus transceiver combines D-type latches and D-type flip-flops to allow data flow in transparent, latched, and clocked modes. It provides for a copy of CLKAB at GTL logic levels (CLKOUT). It also provides a conversion of the GTL clock to a TTL environment (CLKIN).
The B port operates at GTL levels while the A port and control pins are compatible with LVCMOS, LVTTL, or 5-V TTL logic levels.
Data flow in each direction is controlled by output-enable (
and
), latch-enable (LEAB and LEBA),
and clock (CLKAB and CLKBA) inputs. The clock or latch-enable can be
controlled by the chip-enable (
and
) inputs. For
A-to-B data flow, the device operates in the transparent mode when
LEAB is high. When LEAB is low, the A data is latched if
is low and CLKAB is held at a high
or low logic level. If LEAB is low, the A-bus data is stored in the
latch/flip-flop on the low-to-high transition of CLKAB if
is also low. Output-enable
is active-low. When
is low, the outputs are active.
When
is high, the
outputs are in the high-impedance state. Data flow for B to A is
similar to that of A to B but uses
, LEBA, CLKBA, and
.
To ensure the high-impedance state during power-up or power-down,
should be tied
to VCC through a pullup resistor; the minimum value of the
resistor is determined by the current-sinking capability of the
driver.
The SN74LVT16615 is available in TI's shrink small-outline package (DL), which provides twice the I/O pin count and functionality of standard small-outline packages in the same printed-circuit-board area.
The SN74LVT16615 is characterized for operation from 0°C to 70°C.