ClockWorks™
SY89801A
FINAL
HP PA-8000
CLOCK SOURCE
FEATURES
DESCRIPTION
s
s
s
s
s
3.3V, –1.9V power suppies
Differential LVPECL clock input
Differential HSTL/LVPECL outputs
Compatible with HP PA-8000 microprocessors
Low-jitter source for all PA-8000 required timing
signals
s Available in 44-pin MQUAD package
Micrel-Synergy's SY89801A PLL based clock generator
provides, in a single chip, all the necessary clocks for HewlettPackard'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.
2
5
4
3
RCLKLV
RCLKLV
VEE
REF_CLK
VCC
6
1 44 43 42 41 40
7
39
8
38
9
37
10
36
11
12
13
14
35
TOP VIEW
MQUAD
M44-1
34
33
32
15
31
16
30
17
29
VEE
PCLK1
PCLK1
PCLK2
PCLK2
VCC
USYNC
USYNC
NC
NC
VCC
PIN NAMES
FSEL1
FSEL2
VCC
NC
FSEL0
RST
VEE
18 19 20 21 22 23 24 25 26 27 28
VCC
NC
NC
NC
VEEA
NC
NC
FILP
FILN
VCCA
NC
NC
NC
NC
NC
RCLK
RCLK
VEE
NC
NC
REF_CLK
PIN CONFIGURATION
Pin
Function
REF_CLK, REF_CLK
Differential Input Ref. Clock
FILP, FILN
Filter Pins (Positive & Negative)
VCCA, VEEA
Analog VCC, VEE
RST
Master Reset
FSEL2-0
LVPECL Frequency Select Pins
USYNC, USYNC
Diff. HSTL Sync Signal for PA-8000
PCLK1-2, PCLK1-2
Diff. HSTL Processor Clock Signal
RCLK, RCLK
RCLKLV, RCLKLV
Diff. HSTL Runway Clock Signal
Diff. LVPECL Clock Signal
Rev.: E
1
Amendment: /0
Issue Date: November 1998
