廬
FAST CMOS
PARITY BUS
TRANSCEIVER
DESCRIPTION:
IDT54/74FCT833A
IDT54/74FCT833B
Integrated Device Technology, Inc.
FEATURES:
鈥?Equivalent to AMD鈥檚 Am29833 bipolar parity bus
transceiver in pinout/function, speed and output drive
over full temperature and voltage supply extremes
鈥?High-speed bidirectional bus transceiver for processor-
organized devices
鈥?IDT54/74FCT833A equivalent to Am29833A speed and
output drive
鈥?IDT54/74FCT833B 30% faster than Am29833A
鈥?Buffered direction and three-state controls
鈥?Error flag with open-drain output
鈥?I
OL
= 48mA (commercial) and 32mA (military)
鈥?TTL input and output level compatible
鈥?CMOS output level compatible
鈥?Substantially lower input current levels than AMD鈥檚
bipolar Am29800 series (5碌A max.)
鈥?Available in plastic DIP, CERDIP, LCC and SOIC
鈥?Product available in Radiation Tolerant and Radiation
Enhanced versions
鈥?Military product compliant to MIL-STD-883, Class B
The IDT54/74FCT833s are high-performance bus
transceivers designed for two-way communications. They
each contain an 8-bit data path from the R (port) to the T (port),
an 8-bit data path from the T (port) to the R (port), and a 9-bit
parity checker/generator. The error flag can be clocked and
stored in a register and read at the
ERR
output. The clear
(
CLR
) input is used to clear the error flag register.
The output enables
OE
T
and
OE
R
are used to force the
port outputs to the high-impedance state so that the device
can drive bus lines directly. In addition,
OE
R
and
OE
T
can be
used to force a parity error by enabling both lines
simultaneously. This transmission of inverted parity gives the
designer more system diagnostic capability. The devices are
specified at 48mA and 32mA output sink current over the
commercial and military temperature ranges, respectively.
FUNCTIONAL BLOCK DIAGRAM
R
I
8
8
T
I
PARITY
OE
T
OE
R
8
8
S
MUX
9
9-BIT
PARITY TREE
D
P
CLK
CP
CLR
2557 drw 01
Q
Q
ERR
CLR
The IDT logo is a registered trademark of Integrated Device Technology, Inc.
MILITARY AND COMMERCIAL TEMPERATURE RANGES
漏1992
Integrated Device Technology, Inc.
MAY 1992
DSC-4621/2
7.21
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