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GA1088 Datasheet, PDF (1/10 Pages) TriQuint Semiconductor – 11-Output Configurable Clock Buffer
TRIQUINT
S E M I C O N D U C T O R, I N C .
FBIN S1 REFCLK S0 F1
11 10 9
8
7
F0 GND
6
5
GA1088
TEST 12
VDD 13
Q0 14
GND 15
Q1 16
Q2 17
VDD 18
Phase
Detector
VCO
MUX
Divide Logic
÷4, ÷6, or ÷8
Phase
Select
Group Output Buffers
Group
C
A
Group B
4 VDD
3 Q10
2 Q9
1 GND
28 Q8
27 Q7
26 VDD
19 20
GND Q3
21 22 23
Q4 VDD Q5
24 25
Q6 GND
TriQuint’s GA1088 is a configurable clock buffer which generates 11
outputs, operating over a wide range of frequencies — from 18 MHz to
105 MHz. The outputs are available at either 1x and 2x or at 1x and 1/2 x
the reference clock frequency, fREF . When one of the Group A outputs (Q0–
Q2) is used as feedback to the PLL, all Group A outputs will be at fREF , and
all Group B (Q3–Q6) and Group C (Q7–Q10) outputs will be at 2x fREF .
When one of the Group B outputs is used as feedback to the PLL, all Group
A outputs will be at 1/2 x fREF and all Group B and Group C outputs will
be at fREF .
A very stable internal Phase-Locked Loop (PLL) provides low-jitter
operation. This completely self-contained PLL requires no external
capacitors or resistors. The PLL’s voltage-controlled oscillator (VCO) has a
frequency range from 280 MHz to 420 MHz. By feeding back one of the
output clocks to FBIN, the PLL continuously maintains frequency and
phase synchronization between the reference clock (REFCLK) and each of
the outputs. The Shift Select pins select the phase shift (–2t, –t, 0, or +t)
for Group C outputs (Q7–Q10) with respect to REFCLK. The phase shift
increment (t) is equivalent to the VCO’s period (1/fVCO).
11-Output
Configurable
Clock Buffer
Features
• Wide frequency range:
18 MHz to 105 MHz
• Output configurations:
three outputs at 1/2 fREF
three outputs at fREF
four outputs at fREF
with adjustable phase or
two outputs at fREF
four outputs at 2x fREF
four outputs at 2x fREF
with adjustable phase
• Selectable Phase Shift:
–2t, –t, 0, and +t (t = 1/fVCO)
• Low output-to-output skew:
150 ps (max) within a group
• Near-zero propagation delay
–350 ps + 500 ps (max) or
–350 ps +700 ps (max)
• TTL-compatible with 30 mA
output drive
• 28-pin J-lead surface-mount
package
TriQuint’s patented output buffer design delivers a very low output-to-
output skew of 150 ps (max). The GA1088’s symmetrical TTL outputs are
capable of sourcing and sinking 30 mA.
For additional information and latest specifications, see our website: www.triquint.com
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