View MK1491-09_32092.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

MK1491-09
AMD GeodeTM GX2 Clock Source
Description
The MK1491-09 is a low-cost, low-jitter, high-performance clock synthesizer for AMD's Geode-based computer and portable appliance applications. Using patented analog Phased-Locked Loop (PLL) techniques, the device accepts a 14.318 MHz crystal input to produce multiple output clocks. It provides selectable PCI local bus clocks, 48 MHz clocks for Super I/O and USB, as well as multiple Reference outputs. The device has multiple power-down modes to reduce power consumption.
Features
* Packaged in 28-pin SSOP (209 mil body) * Available in Pb (lead) free packaged * Provides all critical timing for the AMD Geode
companion chip
* * * * * * *
Four selectable PCI clocks Three LPC interface clocks One Fixed 66 MHz clock 2 Reference clocks 48 MHz USB and 48 MHz IO support Power down mode Low EMI Enable pin reduces EMI radiation on PCI clocks, LCLKS, and 66 MHz clock
* Operating voltage of 3.3 V 5%
Block Diagram
VDD
6
GND
6
Sel66/33#
4 3
PCI (66/33 MHz) LCLK (33 MHz) 66 MHz
Clocks PD#
USB Clock
48/TS# 48 MHz REFCLK1
XI
14.31818 MHz crystal
Crystal Oscillator
REFCLK0/Spread#
XO
MDS 1491-09 G Integrated Circuit Systems, Inc.
1
525 Race Street, San Jose, CA 95126
Revision 080204 tel (408) 297-1201
www.icst.com
MK1491-09 AMD GeodeTM GX2 Clock Source
Pin Assignment
GND XI XO VDD LCLK0/33M LCLK1/33M GND VDD LCLK2/33M Sel66/33# GND VDD 48M 48M/TS# 1 2 3 4 5 6 7 8 9 10 11 12 13 14 28 27 26 25 24 23 22 21 20 19 18 17 16 15 VDD RefCLK0/Spread# RefCLK1 VDD PCICLK3/33-66M PCICLK2/33-66M GND GND PCICLK1/33-66M VDD PCICLK0/33-66M PD# 66M GND
PCI Frequency Select Table
Sel66/33# 0 1 PCI Frequency 33 MHz 66 MHz
EMI Control
Spread# PCI Low EMI
0 1
ON OFF
Spread direction is DOWN.
Pin Descriptions
Pin Number
1, 7, 11, 15, 21, 22 2 3 4, 8, 12, 19, 25, 28 5, 6, 9 10 13 14 16 17 18, 20, 23, 24 26 27
Pin Name
GND XI XO VDD LCLK Sel66/33# 48M 48M/TS# 66M PD# PCICLK RefCLK1 RefCLK0/ Spread#
Pin Type
P I O P O I O I/O O I O O I/O Connect to Ground.
Pin Description
Crystal connection. Connect to a 14.31818 MHz crystal or input clock. Crystal connection. Connect to a 14.31818 MHz crystal, or leave unconnected. Connect to 3.3 V. 33 MHz low skew clock outputs. Selects frequency on PCICLK. 48 MHz clock output. 48 MHz clock output. TS# is high at power-up. 66 MHz clock output. Power-down input (see table on page 3). 33 to 66 MHz PCI synchronous clock outputs with low skew. Buffered reference output of 14.31818 MHz. Buffered reference output of 14.31818 MHz. Spread select at power-up. For Spread#, see table above.
KEY: I = Input, TI = Tri-level, O = Output, P = Power supply connection, (T)I/O = Input on power up, becomes an Output after 10 ms, Weak internal pull-up resistors are present on TS#, Spread#, PD#, and Sel66/33.
MDS 1491-09 G Integrated Circuit Systems, Inc.
2
525 Race Street, San Jose, CA 95126
Revision 080204 tel (408) 297-1201
www.icst.com
MK1491-09 AMD GeodeTM GX2 Clock Source
Power Down Control Table
PD#
0 1
Functions
All clocks are stopped low. All clocks are running.
Power-on Default Conditions
Pin #
14 27 17 10
Function
TS# Spread# PD# Sel66/33
Default
H H H H All outputs enabled. Spread disabled.
Condition
PCI clocks set to 33.3 MHz. Refer to Power Down Control Table above. PCI frequency = 66 MHz.
MDS 1491-09 G Integrated Circuit Systems, Inc.
3
525 Race Street, San Jose, CA 95126
Revision 080204 tel (408) 297-1201
www.icst.com
MK1491-09 AMD GeodeTM GX2 Clock Source
External Components
The MK1491-09 requires some inexpensive external components for proper operation. Decoupling capacitors of 0.1F should be connected on each VDD pin to ground, as close to the MK1491-09 as possible. A series termination resistor of 33 may be used for each clock output. See the discussion below for other external resistors required for proper I/O operation. The 14.318 MHz oscillator has internal caps that provide the proper load for a parallel resonant crystal with CL=18 pF. For tuning with other values of CL, the formula 2*(CL-18) gives the value of each capacitor that should be connected between X1 and ground and X2 and ground.
I/O Structure
The MK1491-09 provides more functionality in a 28-pin package by using a unique I/O technique. The device checks the status of all I/O pins during power-up. This status (pulled high or low) then determines the frequency selections and power down modes (see the tables on pages 2 and 3). Within 10ms after power up, the inputs change to outputs and the clocks start up. In the diagrams below, the 33 resistors are the normal output termination resistors. The 10k resistor pulls low to generate a logic zero when needed. Weak internal pull-up resistors are present on TS#, Spread#, PD#, and Sel66/33 to pull the pin to high when left floating.
33 For select = 0 (low) I/O 10 k
Do not stuff for "1" selection
To load*
*Note: Do not use a TTL load. This will overcome the 10 k pull-down and force the input to a logic 1.
MDS 1491-09 G Integrated Circuit Systems, Inc.
4
525 Race Street, San Jose, CA 95126
Revision 080204 tel (408) 297-1201
www.icst.com
MK1491-09 AMD GeodeTM GX2 Clock Source
Absolute Maximum Ratings
Stresses above the ratings listed below can cause permanent damage to the MK1491-09. These ratings, which are standard values for ICS commercially rated parts, are stress ratings only. Functional operation of the device at these or any other conditions above those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods can affect product reliability. Electrical parameters are guaranteed only over the recommended operating temperature range.
Item
Supply Voltage, VDD (referenced to VSS) All Inputs and Outputs (referenced to VSS) Ambient Operating Temperature Storage Temperature Junction Temperature Soldering Temperature (10 seconds max) Spread Spectrum Enabled for PCI and LPC Clocks 4.6 V
Rating
-0.5 V to VDD+0.5 V 0 to +70C -65 to +150C 125C 260C 30 kHz min., 33 kHz max.
DC Electrical Characteristics
Unless stated otherwise, VDD = 3.3 V, Ambient Temperature 0 to +70C
Parameter
Operating Voltage Input High Voltage Input Low Voltage Output High Voltage Output Low Voltage Operating Supply Current Clock Disable Mode Supply Current Internal Pull-up Resistor Input Capacitance
Symbol
VDD VIH VIL VOH VOL IDD
Conditions
Min.
3.13 2 VSS
Typ.
3.3
Max.
3.46 VDD 0.8
Units
V V V V
IOH = -12 mA IOL = 12 mA VDD = 3.3 V
2.4 0.4 60 0.5
V mA mA k
All inputs except XI CIN All inputs except XI 5
pF
MDS 1491-09 G Integrated Circuit Systems, Inc.
5
525 Race Street, San Jose, CA 95126
Revision 080204 tel (408) 297-1201
www.icst.com
MK1491-09 AMD GeodeTM GX2 Clock Source
AC Electrical Characteristics
Unless stated otherwise, VDD = 3.3 V, Ambient Temperature 0 to +70 C
Parameter
Input Frequency Output Clock Skew Rate (PCI and LPC), load = 30 pF Output Clock Rise and Fall Time (all but PCI and LPC), load=pF Output Clock Duty Cycle, all MHz Clocks PCI Output to Output Skew, at 33 MHz PCI Output to Output Skew, at 66 MHz LPC Output to Output Skew PCI to LPC Output to Output Skew (note 1) Cycle-to-Cycle Jitter, PCICLK Cycle-to-Cycle Jitter, LPCCLK Cycle-to-Cycle Jitter, USBCLK and 48 MHz Cycle-to-Cycle Jitter, REFCLKs Power-on Time, applied VDD to all Clocks Stable Load Capacitance Crystal
Symbol
FIN
Conditions
Min.
Typ.
14.31818
Max.
Units
MHz
Between 0.4 V and 2.4 V
4
V/ns
tOR, tOF tOD
Between 0.4 V and 2.4 V
0.5
2
ns
At 1.5 V Rising edges at 1.5 V Rising edges at 1.5 V Rising edges at 1.5 V Rising edge at 1.5 V
40
60 500 250 500 500 300 500 500 1400 5 18
% ps ps ps ns ps ps ps ps ms pF
Note 1: Only valid when PCI is at 33 MHz.
Thermal Characteristics
Parameter
Thermal Resistance Junction to Ambient
Symbol
JA JA JA JC
Conditions
Still air 1 m/s air flow 3 m/s air flow
Min.
Typ.
100 80 67 60
Max. Units
C/W C/W C/W C/W
Thermal Resistance Junction to Case
MDS 1491-09 G Integrated Circuit Systems, Inc.
6
525 Race Street, San Jose, CA 95126
Revision 080204 tel (408) 297-1201
www.icst.com
MK1491-09 AMD GeodeTM GX2 Clock Source
Marking Diagram
28 15
IC S
MK1491-09F ###### YYWW
14
1
Marking Diagram (for Pb free)
28 15
IC S
MK1491-09FLN ###### YYWW
14
1
Notes: 1. ###### is the lot code. 2. YYWW is the last two digits of the year, and the week number that the part was assembled. 3. "LN" designates Pb (lead) free.
MDS 1491-09 G Integrated Circuit Systems, Inc.
7
525 Race Street, San Jose, CA 95126
Revision 080204 tel (408) 297-1201
www.icst.com
MK1491-09 AMD GeodeTM GX2 Clock Source
Package Outline and Package Dimensions (28-pin SSOP, 209 mil Body)
Package dimensions are kept current with JEDEC Publication No. 95, MO-150
28
Millimeters Symbol Min Max
Inches Min Max
INDEX AREA
E1
E
12 D
A A1 A2 b c D E E1 e L
-- 2.00 0.05 -- 1.65 1.85 0.22 0.38 0.09 0.25 9.90 10.50 7.40 8.20 5.00 5.60 0.65 Basic 0.55 0.95 0 8
-- 0.079 0.002 -- 0.065 0.073 0.009 0.015 0.0035 0.010 0.390 0.413 0.291 0.323 0.197 0.220 0.0256 Basic 0.022 0.037 0 8
A2 A1
A
The controlling dimensions is inches
c
- Ce
b SEATING PLANE
L
Ordering Information
Part / Order Number
MK1491-09F MK1491-09FTR MK1491-09FLN MK1491-09FLNTR
Marking (see note 1)
MK1491-09F MK1491-09F MK1491-09FLN MK1491-09FLN
Low EMI Shipping Packaging Feature
Yes Yes Yes Yes Tubes Tape and Reel Tubes Tape and Reel
Package
28-pin SSOP 28-pin SSOP 28-pin SSOP 28-pin SSOP
Temperature
0 to +70C 0 to +70C 0 to +70C 0 to +70C
Note: 1. "L" designates Pb (lead) free. While the information presented herein has been checked for both accuracy and reliability, Integrated Circuit Systems (ICS) assumes no responsibility for either its use or for the infringement of any patents or other rights of third parties, which would result from its use. No other circuits, patents, or licenses are implied. This product is intended for use in normal commercial applications. Any other applications such as those requiring extended temperature range, high reliability, or other extraordinary environmental requirements are not recommended without additional processing by ICS. ICS reserves the right to change any circuitry or specifications without notice. ICS does not authorize or warrant any ICS product for use in life support devices or critical medical instruments.
MDS 1491-09 G Integrated Circuit Systems, Inc.
8
525 Race Street, San Jose, CA 95126
Revision 080204 tel (408) 297-1201
www.icst.com

▲Up To Search▲

Price & Availability of MK1491-09

	To Download MK1491-09 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .