CDC9171 Datasheet, PDF (1/5 Pages) Texas Instruments – DVD SYSTEM CLOCK SYNTHESIZER

CDC9171
DVD SYSTEM CLOCK SYNTHESIZER
D Two Integrated PLLs Provide All Digital
Video Disk (DVD) System Frequencies
D Two 27-MHz Reference Clock Outputs
D One 18.432-MHz Reference Clock Output
D One 33.875-MHz Reference Clock Output
D Output Clock Frequencies Derived From an
18.432-MHz Crystal Input
D 3.3-V CMOS Outputs
D Separate Analog Core and Output Supply
Voltage
D Internal Loop Filters for Phase-Lock Loops
Eliminate the Need for External
Components
SCAS558B – DECEMBER 1995 – REVISED OCTOBER 1996
DB PACKAGE
(TOP VIEW)
GND ₁
1X1 ₂
1X2 ₃
V_CC 4
GND 5
PWRDN 6
GND 7
V_CC 8
V_CC 9
GND 10
GND 11
GND 12
24 ^FCLK1
23 ^TEST
22 ^FCLK2
21 V_CC
20 GND
19 NC
18 GND
17 FCLK3
16 V_CC
15 AGND
14 AV_CC
13 FCLK4
description
NC – No internal connection
The CDC9171 is a high-performance clock synthesizer that generates the required clock signals needed for
a DVD system.
The CDC9171 generates all output frequencies from an 18.432-MHz crystal. The 18.432-MHz (FCLK1)
reference clock output is buffered from the integrated oscillators. Two integrated phase-lock loops (PLL)
synthesize the 27-MHz (FCLK2, FCLK3) and the 33.868-MHz (FCLK4) reference clock outputs from the
18.4320-MHz crystal. The oscillator and PLLs can be bypassed in the TEST mode. When TEST is high, input
1X1 is buffered to all outputs.
All clock outputs provide low-jitter clock signals for reliable clock operation. PWRDN is used to disable the PLLs
and output buffers. When low, PWRDN disables the integrated PLLs and forces all outputs to a logic-low state.
Because the CDC9171 is based on PLL circuitry, it requires a stabilization time to achieve phase lock of the PLL.
This stabilization time is required following power up and application of a fixed-frequency, fixed-phase signal
at the 1X1 input and upon activation, following the transition of PWRDN to a logic-high state.
PWRDN
L
H
H
H
INPUTS
TEST
X
L
H
H
FUNCTION TABLE
1X1
X
18.432 MHz
L
H
FCLK1
L
18.432 MHz
L
H
OUTPUTS
FCLK(2–3)
L
27 MHz
L
H
FLCK4
L
33.868 MHz
L
H
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
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Copyright © 1996, Texas Instruments Incorporated
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