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PI74FCT191T Datasheet, PDF (1/6 Pages) Pericom Semiconductor Corporation – High Speed CMOS Presettable Synchronous 4-Bit Binary Counters
PI74FCT191T
(25Ω Series) PI74FCT2191T 1122334455667788990011223344556677889900112233445566778899001122112233445566778899001122334455667788990011223344556677889900112211223344556677889900112233445566778899001122334455667788990011221122334455667788990011223344556677889900112233445566778899001122112233445566778899001122
High Speed CMOS Presettable Synchronous
4-Bit Binary Counters
Product Features
• PI74FCT191/2191T is pin compatible with bipolar FAST™
Series at a higher speed and lower power consumption
• 25Ω series resistor on all outputs (FCT2XXX only)
• TTL input and output levels
• Low ground bounce outputs (25Ω series only)
• Extremely low static power
• Hysteresis on all inputs
• Industrial operating temperature range: –40°C to +85°C
• Packages available:
– 16-pin 150 mil wide plastic QSOP (Q)
– 16-pin 300 mil wide plastic SOIC (S)
Product Description
Pericom Semiconductor’s PI74FCT series of logic circuits are
produced in the Company’s advanced 0.6 micron CMOS
technology, achieving industry leading speed grades. All
PI74FCT2XXX devices have a built-in 25 ohm series resistor on
all outputs to reduce noise due to reflections, thus eliminating the
need for an external terminating resistor.
The PI74FCT191T is a high speed CMOS 4-bit binary up/down
counter. It has a single clock with clock enable and up/down
control inputs and ripple carry output. The 191 has asynchronous
preload inputs which override the count inputs. All inputs have
clamp diodes for undershoot noise suppression. All outputs have
ground bounce suppression.
Logic Block Diagram
U/D
CE
D0-D3
PL
CP
Cup
Q+Cup
- Cdn
Cdn
=F
=0
1
Q3-Q0
25Ω (FCT2XXX ONLY)
TC
25Ω (FCT2XXX ONLY)
RC
25Ω (FCT2XXX ONLY)
PS2084B 01/13/97