SY89801A Datasheet, PDF (1/5 Pages) Micrel Semiconductor – HP PA-8000 CLOCK SOURCE

HP PA-8000
CLOCK SOURCE
ClockWorks™
PRELIMINARY
SY89801A
FEATURES
s 3.3V, –1.9V power suppies
s Differential LVPECL clock input
s Differential HSTL/LVPECL outputs
s Compatible with HP PA-8000 microprocessors
s Low-jitter source for all PA-8000 required timing
signals
s Available in 44-pin MQUAD package
PIN CONFIGURATION
VEEA
NC
NC
FILP
FILN
VCCA
NC
NC
NC
NC
NC
6 5 4 3 2 1 44 43 42 41 40
7
39
8
38
9
37
10
36
11
TOP VIEW
35
12
MQUAD
34
13
M44-1
33
14
32
15
31
16
30
17
29
18 19 20 21 22 23 24 25 26 27 28
VEE
PCLK1
PCLK1
PCLK2
PCLK2
VCC
USYNC
USYNC
NC
NC
VCC
DESCRIPTION
Micrel-Synergy's SY89801A PLL based clock generator
provides, in a single chip, all the necessary clocks for Hewlett-
Packard's PA-8000 Microprocessor.
Utilizing Micrel-Synergy's advanced PLL technology, the
SY89801A accepts a Positive-ECL (PECL) reference clock
input at 100MHz-132MHz, and provides precisely aligned,
ultra-low-jitter ratios of frequencies necessary for the operation
of the processor. In addition, the SY89801A provides the
"USYNC" synchronizing signals as required by the PA-8000.
The frequency ratios are 1:1, 4:3, 3:2, 5:3 and 2:1.
To facilitate direct interfacing to the PA-8000, the SY89801A
operates across +3.3 volt and -1.9 volt supplies. The processor
clock (PCLK), runway clock (RCLK) , and USYNC outputs are
HSTL-compatible. Additionally, there is a PECL-compatible
runway clock output (RCLKLV). The SY89801A requires only
a simple external series-RC loop filter.
Coupling Micrel-Synergy's advanced PLL technology with
our proprietary ASSET bipolar process has produced a
Timing Generator IC which meets the stringent requirements
of the PA-8000 µP, while setting a new standard for
performance and flexibility.
PIN NAMES
Pin
REF_CLK, REF_CLK
FILP, FILN
VCCA, VEEA
RST
FSEL2-0
USYNC, USYNC
PCLK1-2, PCLK1-2
RCLK, RCLK
RCLKLV, RCLKLV
Function
Differential Input Ref. Clock
Filter Pins (Positive & Negative)
Analog VCC, VEE
Master Reset
LVPECL Frequency Select Pins
Diff. HSTL Sync Signal for PA-8000
Diff. HSTL Processor Clock Signal
Diff. HSTL Runway Clock Signal
Diff. LVPECL Clock Signal
Rev.: E
Amendment: /0
1
Issue Date: November 1998