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Packages available:
聳 56-pin 240 mil wide plastic TSSOP (A56)
聳 56-pin 300 mil wide plastic SSOP (V56)
Product Description
Pericom Semiconductor聮s PI74ALVCH series of logic circuits are
produced in the Company聮s advanced 0.5 micron CMOS technology,
achieving industry leading speed.
The PI74ALVCH1622601S uses D-type latches and D-type flip-flops
with 3-state outputs to allow data flow in transparent, latched, and
clocked modes.
Data flow in each direction is controlled by Output Enable (OEAB
and OEBA), Latched Enable (LEAB and LEBA), and Clock
(CLKAB and CLKBA) inputs. The clock can be controlled by the
Clock Enable (CLKENAB and CLKENBA) 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 CLKAB is
held at a high or low logic level. If LEAB is low, the A-bus is stored
in the latch/flip-flop on the low-to-high transition of CLKAB.
When OEAB is low, the outputs are active. When OEAB 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 OEBA,
LEBA, CLKBA, and CLKENBA.
To reduce overshoot and undershoot, the inputs/outputs include
26鈩?series resistors.
To ensure the high-impedance state during power up or power
down, OE should be tied to Vcc through a pull-up resistor; the
minimum value of the resistor is determined by the current-sinking
capability of the driver.
Logic Block Diagram
OEAB
CLKENAB
CLKAB
LEAB
LEBA
CLKBA
CLKENBA
OEBA
A1
1
56
55
2
28
30
29
27
3
CE
1D
C1
CLK
CE
1D
C1
CLK
The PI74ALVCH1622601S has 聯(lián)Bus Hold聰 which retains the data
input聮s last state whenever the data input goes to high-impedance
preventing 聯(lián)floating聰 inputs and eliminating the need for pullup/
down resistors.
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