IDT5V991A Datasheet, PDF (1/8 Pages) Integrated Device Technology – 3.3V PROGRAMMABLE SKEW PLL CLOCK DRIVER TURBOCLOCK

IDT5V991A
3.3V PROGRAMMABLE SKEW PLL CLOCK DRIVER TURBOCLOCK
COMMERCIAL AND INDUSTRIAL TEMPERATURE RANGES
3.3V PROGRAMMABLE
SKEW PLL CLOCK DRIVER
TURBOCLOCK™
IDT5V991A
FEATURES:
• REF is 5V tolerant
• 4 pairs of programmable skew outputs
• Low skew: 200ps same pair, 250ps all outputs
• Selectable positive or negative edge synchronization:
Excellent for DSP applications
• Synchronous output enable
• Output frequency: 3.75MHz to 85MHz
• 2x, 4x, 1/2, and 1/4 outputs
• 3 skew grades:
IDT5V991A-2: tSKEW0<250ps
IDT5V991A-5: tSKEW0<500ps
IDT5V991A-7: tSKEW0<750ps
• 3-level inputs for skew and PLL range control
• PLL bypass for DC testing
• External feedback, internal loop filter
• 12mA balanced drive outputs
• Low Jitter: <200ps peak-to-peak
• Available in 32-pin PLCC Package
DESCRIPTION:
The IDT5V991A is a high fanout 3.3V PLL based clock driver intended
for high performance computing and data-communications applications. A
key feature of the programmable skew is the ability of outputs to lead or lag
the REF input signal. The IDT5V991A has eight programmable skew
outputs in four banks of 2. Skew is controlled by 3-level input signals that
may be hard-wired to appropriate HIGH-MID-LOW levels.
When the GND/sOE pin is held low, all the outputs are synchronously
enabled. However, if GND/sOE is held high, all the outputs except 3Q0 and
3Q1 are synchronously disabled.
Furthermore, when the VCCQ/PE is held high, all the outputs are
synchronized with the positive edge of the REF clock input. When VCCQ/
PE is held low, all the outputs are synchronized with the negative edge of
REF. Both devices have LVTTL outputs with 12mA balanced drive outputs.
FUNCTIONAL BLOCK DIAGRAM
GND/sOE
1Q0
Skew
Select
33
1Q1
1F1:0
VCCQ/PE
2Q0
Skew
Select
REF
33
2Q1
PLL
2F1:0
FB
3Q0
3
Skew
Select
33
3Q1
FS
3F1:0
4Q0
Skew
Select
33
4Q1
4F1:0
The IDT logo is a registered trademark of Integrated Device Technology, Inc.
COMMERCIAL AND INDUSTRIAL
c 2001 Integrated Device Technology, Inc.
TEMPERATURE
1
RANGES
SEPTEMBER 2001
DSC 5963/3