CYPRESS CY28RS480ZXC

CY28RS480
Clock Generator for ATI RS480 Chipset
• I2C support with readback capabilities
Features
• Ideal Lexmark Spread Spectrum profile for maximum
electromagnetic interference (EMI) reduction
• Supports AMD CPU
• 200-MHz differential CPU clock pairs
• 3.3V power supply
• 100-MHz differential SRC clocks
• 56-pin SSOP and TSSOP packages
• 48-MHz USB clock
• 33-MHz PCI clock
CPU
SRC
HTT66
PCI
REF
USB_48
x2
x8
x1
x1
x3
x1
• 66-MHz HyperTransport clock
Block Diagram
XIN
XOUT
CPU_STP#
CLKREQ[0:1]#
XTAL
OSC
PLL1
Pin Configuration
VDD_REF
REF[0:2]
PLL Ref Freq
VDD_CPU
CPUT[0:1], CPUC[0:1],
Divider
Network
VDD_SRC
SRCT[0:5],SRCC[0:5]
VDD_SRCS
SRCST[0:1],SRCSC[0:1]
IREF
VDD_HTT
HTT66
PD
VDD_48 MHz
PLL2
SDATA
SCLK
USB_48
I2C
Logic
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
CY28RS480
VDD_PCI
PCI
XIN
XOUT
VDD_48
USB_48
VSS_48
NC
SCLK
SDATA
NC
CLKREQ#0
CLKREQ#1
SRCT5
SRCC5
VDD_SRC
VSS_SRC
SRCT4
SRCC4
SRCT3
SRCC3
VSS_SRC
VDD_SRC
SRCT2
SRCC2
SRCT1
SRCC1
VSS_SRC
SRCST1
SRCSC1
56
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
VDD_REF
VSS_REF
REF0
REF1
REF2
VDD_PCI
PCI0
VSS_PCI
VDD_HTT
HTT66
VSS_HTT
CPUT0
CPUC0
VDD_CPU
VSS_CPU
CPUT1
CPUC1
VDDA
VSSA
IREF
VSS_SRC1
VDD_SRC1
SRCT0
SRCC0
VDD_SRCS
VSS_SRCS
SRCST0
SRCSC0
56 SSOP/TSSOP
Cypress Semiconductor Corporation
Document #: 38-07638 Rev. *C
•
3901 North First Street
•
San Jose, CA 95134
•
408-943-2600
Revised February 21, 2005
CY28RS480
Pin Description
Pin No.
Name
Type
Description
41,40,45,44
CPUT/C
50
PCI0
O
33-MHz clock output.
37
IREF
I
A precision resistor attached to this pin is connected to the internal current
reference.
52, 53, 54
REF[2:0]
7
SCLK
8
SDATA
27, 28, 30, 29
SRCST/C[1:0]
12, 13, 16,
17, 18, 19,
22, 23, 24,
25, 34, 33
SRCT/C[5:0]
10,11
CLKREQ#[0:1]
4
USB_48
47
HTT66
O, DIF Differential CPU clock outputs. AMD K8 buffer (200 Mhz).
O, SE 14.318-MHz REF clock output. Intel Type-5 buffer.
I,PU
SMBus-compatible SCLOCK.This pin has an internal pull-up, but is tri-stated in
power-down.
I/O,PU SMBus-compatible SDATA.This pin has an internal pull-up, but is tri-stated in
power-down.
O, DIF Differentials Selectable serial reference clock. Intel Type-X buffer.
Includes overclock support through SMBUS
O, DIF 100-MHz differential serial reference clock. Intel Type-X buffer.
I, SE, Output Enable control for SRCT/C. Output enable control required by Minicard
PD specification. This pin has an internal pull-down.
0 = Selected SRC outputs are enabled, 1 = Selected SRC outputs are disabled
O, SE 48-MHz clock output. Intel Type-3A buffer.
O, SE 66-MHz clock output. Intel Type-5 buffer.
3
VDD_48
PWR
3.3V power supply for USB outputs
43
VDD_CPU
PWR
3.3V power supply for CPU outputs
51
VDD_PCI
PWR
3.3V power supply for PCI outputs
56
VDD_REF
PWR
3.3V power supply for REF outputs
48
VDD_HTT
PWR
3.3V power supply for Hyper Transport outputs
14, 21
VDD_SRC
PWR
3.3V power supply for SRC outputs
35
VDD_SRC1
PWR
3.3V power supply for SRC outputs
32
VDD_SRCS
PWR
3.3V power supply for SRCS outputs
39
VDDA
PWR
3.3V Analog Power for PLLs
5
VSS_48
GND
Ground for USB outputs
42
VSS_CPU
GND
Ground for CPU outputs
49
VSS_PCI
GND
Ground for PCI outputs
55
VSS_REF
GND
Ground for REF outputs
15, 20, 26
VSS_SRC
GND
Ground for SRC outputs
36
VSS_SRC1
GND
Ground for SRC outputs
31
VSS_SRCS
GND
Ground for SRCS outputs
46
VSS_HTT
GND
Ground for HyperTransport outputs
38
VSSA
GND
Analog Ground
1
XIN
I
14.318-MHz Crystal Input
2
XOUT
O
14.318-MHz Crystal Output
6, 9
NC
Document #: 38-07638 Rev. *C
No Connects
Page 2 of 15
CY28RS480
Serial Data Interface
Data Protocol
To enhance the flexibility and function of the clock synthesizer,
a two-signal serial interface is provided. Through the Serial
Data Interface, various device functions, such as individual
clock output buffers, can be individually enabled or disabled.
The registers associated with the Serial Data Interface
initializes to their default setting upon power-up, and therefore
use of this interface is optional. Clock device register changes
are normally made upon system initialization, if any are
required. The interface cannot be used during system
operation for power management functions.
The clock driver serial protocol accepts byte write, byte read,
block write, and block read operations from the controller. For
block write/read operation, the bytes must be accessed in
sequential order from lowest to highest byte (most significant
bit first) with the ability to stop after any complete byte has
been transferred. For byte write and byte read operations, the
system controller can access individually indexed bytes. The
offset of the indexed byte is encoded in the command code,
as described in Table 1.
The block write and block read protocol is outlined in Table 2
while Table 3 outlines the corresponding byte write and byte
read protocol. The slave receiver address is 11010010 (D2h).
Table 1. Command Code Definition
Bit
7
Description
0 = Block read or block write operation, 1 = Byte read or byte write operation
(6:5)
Chip select address, set to ‘00’ to access device
(4:0)
Byte offset for byte read or byte write operation. For block read or block write operations, these bits should be '00000'
Table 2. Block Read and Block Write Protocol
Block Write Protocol
Bit
1
8:2
Description
Start
Write
10
18:11
19
27:20
28
36:29
37
45:38
Bit
1
Slave address – 7 bits
9
Block Read Protocol
8:2
Description
Start
Slave address – 7 bits
9
Write
Acknowledge from slave
10
Acknowledge from slave
Command Code – 8 bits
18:11
Command Code – 8 bits
Acknowledge from slave
19
Acknowledge from slave
Byte Count – 8 bits
20
Repeat start
Acknowledge from slave
Data byte 1 – 8 bits
Acknowledge from slave
Data byte 2 – 8 bits
46
Acknowledge from slave
....
Data Byte /Slave Acknowledges
....
Data Byte N – 8 bits
....
Acknowledge from slave
....
Stop
27:21
Slave address – 7 bits
28
Read = 1
29
Acknowledge from slave
37:30
38
46:39
47
55:48
Byte Count from slave – 8 bits
Acknowledge
Data byte 1 from slave – 8 bits
Acknowledge
Data byte 2 from slave – 8 bits
56
Acknowledge
....
Data bytes from slave / Acknowledge
....
Data Byte N from slave – 8 bits
....
NOT Acknowledge
Table 3. Byte Read and Byte Write Protocol
Byte Write Protocol
Bit
1
8:2
Description
Start
Slave address – 7 bits
Byte Read Protocol
Bit
1
8:2
Description
Start
Slave address – 7 bits
9
Write
9
Write
10
Acknowledge from slave
10
Acknowledge from slave
Document #: 38-07638 Rev. *C
Page 3 of 15
CY28RS480
Table 3. Byte Read and Byte Write Protocol (continued)
Byte Write Protocol
Bit
18:11
19
27:20
Byte Read Protocol
Description
Bit
Description
Command Code – 8 bits
18:11
Command Code – 8 bits
Acknowledge from slave
19
Acknowledge from slave
Data byte – 8 bits
20
Repeated start
28
Acknowledge from slave
29
Stop
27:21
Slave address – 7 bits
28
Read
29
Acknowledge from slave
37:30
Data from slave – 8 bits
38
NOT Acknowledge
39
Stop
Control Registers
Byte 0:Control Register 0
Bit
@Pup
Name
Description
7
1
SRC[T/C]5
SRC[T/C]5 Output Enable
0 = Disable (Hi-Z), 1 = Enable
6
1
SRC[T/C]4
SRC[T/C]4 Output Enable
0 = Disable (Hi-Z), 1 = Enable
5
1
SRC[T/C]3
SRC[T/C]3 Output Enable
0 = Disable (Hi-Z), 1 = Enable
4
1
SRC[T/C]2
SRC[T/C]2 Output Enable
0 = Disable (Hi-Z), 1 = Enable
3
1
SRC[T/C]1
SRC[T/C]1 Output Enable
0 = Disable (Hi-Z), 1 = Enable
2
1
SRC [T/C]0
SRC[T/C]0 Output Enable
0 = Disable (Hi-Z), 1 = Enable
1
1
SRCS[T/C]1
SRCS[T/C]1 Output Enable
0 = Disable (Hi-Z), 1 = Enable
0
1
SRCS[T/C]0
SRCS[T/C]0 Output Enable
0 = Disable (Hi-Z), 1 = Enable
Byte 1: Control Register 1
Bit
@Pup
Name
7
1
REF2
REF2 Output Enable
0 = Disable, 1 = Enable
6
1
REF1
REF1 Output Enable
0 = Disable, 1 = Enable
5
1
REF0
REF0 Output Enable
0 = Disable, 1 = Enable
4
1
PCI0
PCI0 Output Enable
0 = Disable, 1 = Enable
3
1
USB_48
2
1
RESERVED
1
1
CPU[T/C]1
CPU[T/C]1 Output Enable
0 = Disable (Hi-Z), 1 = Enable
0
1
CPU[T/C]0
CPU[T/C]0 Output Enable
0 = Disable (Hi-Z), 1 = Enable
Document #: 38-07638 Rev. *C
Description
USB_48MHz Output Enable
0 = Disable, 1 = Enable
RESERVED
Page 4 of 15
CY28RS480
Byte 2: Control Register 2
Bit
@Pup
Name
Description
7
1
CPUT/C
SRCT/C
Spread Spectrum Selection
‘0’ = –0.35%
‘1’ = –0.50%
6
1
USB_48
48-MHz Output Drive Strength
0 = 2x, 1 = 1x
5
1
PCI
33-MHz Output Drive Strength
0 = 2x, 1 = 1x
4
0
Reserved
Reserved
3
1
Reserved
Reserved
2
0
CPU
SRC
1
1
Reserved
Reserved
0
1
Reserved
Reserved
CPU/SRC Spread Spectrum Enable
0 = Spread off, 1 = Spread on
Byte 3: Control Register 3
Bit
@Pup
Name
7
1
CLKREQ#
Description
6
0
CPU
CPU pd drive mode
0 = CPU clocks driven when power-down, 1 = CPU clocks tri-state
5
1
SRC
SRC pd drive mode
0 = SRC clocks driven when power-down, 1 = SRC clocks tri-state
4
0
Reserved
Reserved
3
1
Reserved
Reserved
2
1
Reserved
Reserved
1
1
Reserved
Reserved
0
1
HTT66
CLKREQ# drive mode
0 = SRC clocks driven when stopped, 1 = SRC clocks tri-state when
stopped
HTT66 Output Drive Strength0 = High drive, 1 = Low drive.
Byte 4: Control Register 4
Bit
@Pup
Name
7
0
SRC[T/C]5
SRC[T/C]5 CLKREQ0 control
1 = SRC[T/C]5 stoppable by CLKREQ#0 pin
0 = SRC[T/C]5 free running
6
0
SRC[T/C]4
SRC[T/C]4 CLKREQ#0 control
1 = SRC[T/C]4 stoppable by CLKREQ#0 pin
0 = SRC[T/C]4 free running
5
0
SRC[T/C]3
SRC[T/C]3 CLKREQ#0 control
1 = SRC[T/C]3 stoppable by CLKREQ#0 pin
0 = SRC[T/C]3 free running
4
0
SRC[T/C]2
SRC[T/C]2 CLKREQ#0 control
1 = SRC[T/C]2 stoppable by CLKREQ#0 pin
0 = SRC[T/C]2 free running
3
0
SRC[T/C]1
SRC[T/C]1 CLKREQ#0 control
1 = SRC[T/C]1 stoppable by CLKREQ#0 pin
0 = SRC[T/C]1 free running
2
0
SRC[T/C]0
SRC[T/C]0 CLKREQ#0 control
1 = SRC[T/C]1 stoppable by CLKREQ#0 pin
0 = SRC[T/C]1 free running
1
1
HTT66
Document #: 38-07638 Rev. *C
Description
HTT66 Output enable
0 = Disabled, 1 = Enabled
Page 5 of 15
CY28RS480
Byte 4: Control Register 4 (continued)
Bit
@Pup
Name
Description
0
1
Reserved
Reserved
Description
SRC[T/C]5 CLKREQ#1 control
1 = SRC[T/C]5 stoppable by CLKREQ#1 pin
0 = SRC[T/C]5 free running
SRC[T/C]4 CLKREQ#1 control
1 = SRC[T/C]4 stoppable by CLKREQ#1 pin
0 = SRC[T/C]4 free running
SRC[T/C]3 CLKREQ#1 control
1 = SRC[T/C]3 stoppable by CLKREQ#1 pin
0 = SRC[T/C]3 free running
SRC[T/C]2 CLKREQ#1 control
1 = SRC[T/C]2 stoppable by CLKREQ#1 pin
0 = SRC[T/C]2 free running
SRC[T/C]1 CLKREQ#1 control
1 = SRC[T/C]1 stoppable by CLKREQ#1 pin
0 = SRC[T/C]1 free running
SRC[T/C]0 CLKREQ#1 control
1 = SRC[T/C]1 stoppable by CLKREQ#1 pin
0 = SRC[T/C]1 free running
Reserved
Reserved
Byte 5: Control Register 5
Bit
7
@Pup
0
Name
SRC[T/C]5
6
0
SRC[T/C]4
5
0
SRC[T/C]3
4
0
SRC[T/C]2
3
0
SRC[T/C]1
2
0
SRC[T/C]0
1
0
0
0
Reserved
Reserved
Byte 6: Control Register 6
Bit
@Pup
Name
Description
7
0
TEST_SEL
6
0
TEST_MODE
5
0
REF
4
1
Reserved
Reserved
3
HW
Reserved
Reserved
2
HW
Reserved
Reserved
1
HW
Reserved
Reserved
0
HW
Reserved
Reserved
REF/N or Three-state Select
1 = REF/N Clock, 0 = Three-state
Test Clock Mode Entry Control
1 = REF/N or Tri-state mode, 0 = Normal operation
REF Output drive strength
0 = Low drive, 1 = High drive
Byte 7: Vendor ID
Bit
@Pup
7
0
Revision Code Bit 3
6
0
Revision Code Bit 2
5
0
Revision Code Bit 1
4
1
Revision Code Bit 0
3
1
Vendor ID Bit 3
2
0
Vendor ID Bit 2
1
0
Vendor ID Bit 1
0
0
Vendor ID Bit 0
Document #: 38-07638 Rev. *C
Name
Description
Page 6 of 15
CY28RS480
Table 4. Crystal Recommendations
Frequency
(Fund)
Cut
Loading Load Cap
Drive
(max.)
Shunt Cap
(max.)
Motional
(max.)
Tolerance
(max.)
Stability
(max.)
Aging
(max.)
14.31818 MHz
AT
Parallel
0.1 mW
5 pF
0.016 pF
35 ppm
30 ppm
5 ppm
20 pF
Crystal Recommendations
The CY28RS480 requires a Parallel Resonance Crystal.
Substituting a series resonance crystal will cause the
CY28RS480 to operate at the wrong frequency and violate the
ppm specification. For most applications there is a 300-ppm
frequency shift between series and parallel crystals due to
incorrect loading.
series with the crystal, trim capacitors (Ce1,Ce2) should be
calculated to provide equal capacitive loading on both sides.
Clock Chip
Ci2
Ci1
Pin
3 to 6p
Crystal Loading
Crystal loading plays a critical role in achieving low ppm performance. To realize low ppm performance, the total capacitance
the crystal will see must be considered to calculate the appropriate capacitive loading (CL).
Figure 1 shows a typical crystal configuration using the two
trim capacitors. An important clarification for the following
discussion is that the trim capacitors are in series with the
crystal not parallel. It’s a common misconception that load
capacitors are in parallel with the crystal and should be
approximately equal to the load capacitance of the crystal.
This is not true.
X2
X1
Cs1
Cs2
Trace
2.8pF
XTAL
Ce1
Ce2
Trim
33pF
Figure 2. Crystal Loading Example
As mentioned previously, the capacitance on each side of the
crystal is in series with the crystal. This mean the total capacitance on each side of the crystal must be twice the specified
load capacitance (CL). While the capacitance on each side of
the crystal is in series with the crystal, trim capacitors
(Ce1,Ce2) should be calculated to provide equal capacitance
loading on both sides.
Use the following formulas to calculate the trim capacitor
values for Ce1 and Ce2.
Figure 1. Crystal Capacitive Clarification
Load Capacitance (each side)
Ce = 2 * CL – (Cs + Ci)
Calculating Load Capacitors
In addition to the standard external trim capacitors, trace
capacitance and pin capacitance must also be considered to
correctly calculate crystal loading. As mentioned previously,
the capacitance on each side of the crystal is in series with the
crystal. This means the total capacitance on each side of the
crystal must be twice the specified crystal load capacitance
(CL). While the capacitance on each side of the crystal is in
Total Capacitance (as seen by the crystal)
CLe
=
1
1
( Ce1 + Cs1
+ Ci1 +
1
Ce2 + Cs2 + Ci2
)
CL ....................................................Crystal load capacitance
CLe ......................................... Actual loading seen by crystal
using standard value trim capacitors
Ce ..................................................... External trim capacitors
Cs ..............................................Stray capacitance (terraced)
Ci .......................................................... Internal capacitance
(lead frame, bond wires etc.)
CL ....................................................Crystal load capacitance
CLe ......................................... Actual loading seen by crystal
using standard value trim capacitors
Ce ..................................................... External trim capacitors
Cs ..............................................Stray capacitance (terraced)
Ci .......................................................... Internal capacitance
(lead frame, bond wires etc.)
Document #: 38-07638 Rev. *C
Page 7 of 15
CY28RS480
CLK_REQ[0:1]# Description
The CLKREQ#[1:0] signals are active low input used for clean
stopping and starting selected SRC outputs. The outputs
controlled by CLKREQ#[1:0] are determined by the settings in
register bytes 4 and 5. The CLKREQ# signal is a debounced
signal in that its state must remain unchanged during two
consecutive rising edges of DIFC to be recognized as a valid
assertion or deassertion. (The assertion and deassertion of
this signal is absolutely asynchronous.)
CLK_REQ[0:1]# Deassertion [Low to High Transition]
The impact of deasserting the CLKREQ#[1:0] pins is all DIF
outputs that are set in the control registers to stoppable via
assertion of CLKREQ#[1:0] are to be stopped after their next
transition. When the control register CLKREQ# drive mode bit
is programmed to ‘0’, the final state of all stopped SRC signals
is SRCT clock = High and SRCC = Low. There is to be no
change to the output drive current values, SRCT will be driven
high with a current value equal 6 x Iref,. When the control
register CLKREQ# drive mode bit is programmed to ‘1’, the
final state of all stopped DIF signals is low, both SRCT clock
and SRCC clock outputs will not be driven.
CLK_REQ[0:1]# Assertion [High to Low Transition]
All differential outputs that were stopped are to resume normal
operation in a glitch free manner. The maximum latency from
the Assertion to active outputs is between 2–6 SRC clock
periods (2 clocks are shown) with all SRC outputs resuming
simultaneously. If the CLKREQ# drive mode bit is
programmed to ‘1’ three-state), the all stopped SRC outputs
must be driven high within 10 ns of CLKREQ#[1:0] Assertion
to a voltage greater than 200 mV.
CLKREQ#X
SRCT(free running)
SRCC(free running)
SRCT(stoppable)
SRCT(stoppable)
Figure 3. CLK_REQ#[0:1] Assertion/Deassertion Waveform
Document #: 38-07638 Rev. *C
Page 8 of 15
CY28RS480
Absolute Maximum Conditions
Parameter
Description
Condition
Min.
Max.
Unit
VDD
Core Supply Voltage
–0.5
4.6
V
VDDA
Analog Supply Voltage
–0.5
4.6
V
VIN
Input Voltage
Relative to VSS
–0.5
VDD+0.5
VDC
TS
Temperature, Storage
Non-functional
–65
+150
°C
TA
Temperature, Operating Ambient
Functional
0
70
°C
TJ
Temperature, Junction
Functional
–
150
°C
ESDHBM
ESD Protection (Human Body Model)
MIL-STD-883, Method 3015
2000
–
V
ØJC
Dissipation, Junction to Case
Mil-Spec 883E Method 1012.1
–
20
°C/W
ØJA
Dissipation, Junction to Ambient
JEDEC (JESD 51)
–
60
°C/W
UL-94
Flammability Rating
At 1/8 in.
MSL
Moisture Sensitivity Level
V–0
1
Multiple Supplies: The voltage on any input or I/O pin cannot exceed the power pin during power-up. Power supply sequencing is NOT required.
DC Electrical Specifications
Parameter
Description
VDD_REF, 3.3V Operating Voltage
VDD_CPU,
VDD_PCI,
VDD_SRC,
VDD_SRC1,
VDD_SRCS
VDD_48
Condition
3.3V ± 5%
VILSMBUS
Input Low Voltage
SDATA, SCLK
VIHSMBUS
Input High Voltage
SDATA, SCLK
VIL
Input Low Voltage
VDD
VIH
Input High Voltage
IIL
Input Leakage Current
Except pull-ups or pull-downs 0<VIN<VDD
Min.
Max.
Unit
3.135
3.465
V
–
1.0
V
2.2
-
V
VSS–0.3
0.8
V
2.0
VDD+0.3
V
–5
5
mA
VOL
Output Low Voltage
IOL = 1 mA
–
0.4
V
VOH
Output High Voltage
IOH = 1 mA
2.4
–
V
IOZ
High-Impedance Output Current
–10
10
µA
CIN
Input Pin Capacitance
3
5
pF
COUT
LIN
Output Pin Capacitance
3
5
pF
Pin Inductance
–
7
nH
VXIH
Xin High Voltage
0.7*VDD
VDD
V
VXIL
Xin Low Voltage
0
0.3*VDD
V
IDD
Dynamic Supply Current
At max load and frequency
–
450
mA
IPDD
Power Down Supply Current
PD asserted, Outputs driven
–
75
mA
IPDT
Power Down Supply Current
PD asserted, Outputs Hi-Z
–
12
mA
Condition
Min.
Max.
Unit
47.5
52.5
%
69.841
71.0
ns
AC Electrical Specifications
Parameter
Description
Crystal
TDC
XIN Duty Cycle
The device will operate reliably with input
duty cycles up to 30/70 but the REF clock
duty cycle will not be within specification
TPERIOD
XIN Period
When XIN is driven from an external
clock source
Document #: 38-07638 Rev. *C
Page 9 of 15
CY28RS480
AC Electrical Specifications (continued)
Condition
Min.
Max.
Unit
TR / TF
Parameter
XIN Rise and Fall Times
Description
Measured between 0.3VDD and 0.7VDD
–
10.0
ns
TCCJ
XIN Cycle to Cycle Jitter
As an average over 1-µs duration
–
500
ps
LACC
Long-term Accuracy
Over 150 ms
–
300
ppm
Measured @ test load using VOCM
±400 mV, 0.85 to 1.65
2
7
V/ns
CPU Outputs
TR/TF
Output Slew Rate
VDIFF
Differential Voltage
Measured at load single ended
0.4
2.3
V
TSKEW
Any CPU to CPU Clock Skew
Measured at crossing point VOX
–
250
ps
_ VDIFF
Change in VDIFF_DC Magnitude
Measured at load single ended
–150
150
mV
VCM
Common Mode Voltage
Measured at load single ended
1.05
1.45
V
_ VCM
Change in VCM
Measured at load single ended
–200
200
mV
TDC
Duty Cycle
Measured at VOX
45
55
%
TJCYC
Cycle to Cycle Jitter
Measured at VOX
0
200
ps
SRC
TDC
SRCT and SRCC Duty Cycle
Measured at crossing point VOX
45
55
%
TPERIOD
100-MHz SRCT and SRCC Period
Measured at crossing point VOX
9.997001
10.00300
ns
TPERIODSS
100-MHz SRCT and SRCC Period, SSC Measured at crossing point VOX
9.997001
10.05327
ns
TPERIODAbs
100-MHz SRCT and SRCC Absolute
Period
Measured at crossing point VOX
10.12800
9.872001
ns
TPERIODSSAbs 100-MHz SRCT and SRCC Absolute
Period, SSC
Measured at crossing point VOX
9.872001
10.17827
ns
TSKEW
Any SRCT/C to SRCT/C Clock Skew
Measured at crossing point VOX
–
250
ps
TSKEW
Any SRCS clock to Any SRCS clock
Skew
Measured at crossing point VOX
–
250
ps
TCCJ
SRCT/C Cycle to Cycle Jitter
Measured at crossing point VOX
–
125
ps
LACC
SRCT/C Long Term Accuracy
Measured at crossing point VOX
TR / TF
SRCT and SRCC Rise and Fall Times
Measured from VOL = 0.175 to
VOH = 0.525V
TRFM
Rise/Fall Matching
Determined as a fraction of
2*(TR – TF)/(TR + TF)
∆TR
Rise TimeVariation
∆TF
Fall Time Variation
VHIGH
Voltage High
Math averages Figure 5
VLOW
Voltage Low
Math averages Figure 5
–150
–
mv
VOX
Crossing Point Voltage at 0.7V Swing
250
550
mV
–
300
ppm
175
700
ps
–
20
%
–
125
ps
–
125
ps
660
850
mv
VOVS
Maximum Overshoot Voltage
–
VHIGH + 0.3
V
VUDS
Minimum Undershoot Voltage
–0.3
–
V
VRB
Ring Back Voltage
–
0.2
V
–
66.67
MHz
See Figure 5. Measure SE
HTT66 HyperTransport Output
F66
Operating Frequency
TDC
Duty Cycle
Measured at 1.5V
45
55
%
TR/TF
Slew Rate
Measured at 20% and 60%
0.9
6.5
V/ns
TCCJ
Cycle to Cycle jitter
Measured at 1.5V
–
450
ps
TSKEW
HTT66 clock to PCI clock Skew
Measurement at 1.5V
–
500
ps
Document #: 38-07638 Rev. *C
Page 10 of 15
CY28RS480
AC Electrical Specifications (continued)
Parameter
Description
Condition
Min.
Max.
Unit
PCI
TDC
PCI Duty Cycle
Measurement at 1.5V
45
55
%
TPERIOD
Spread Disabled PCI Period
Measurement at 1.5V
29.99100
30.00900
ns
TPERIODSS
Spread Enabled PCI Period, SSC
Measurement at 1.5V
29.9910
30.15980
ns
TPERIODAbs
Spread Disabled PCI Period
Measurement at 1.5V
29.49100
30.50900
ns
TPERIODSSAbs Spread Enabled PCI Period, SSC
Measurement at 1.5V
29.49100
30.65980
ns
THIGH
PCI high time
Measurement at 2.4V
12.0
–
ns
TLOW
PCI low time
Measurement at 0.4V
12.0
–
ns
TR / TF
PCI rise and fall times
Measured between 0.8V and 2.0V
1.0
4.0
V/ns
TCCJ
PCI Cycle to Cycle Jitter
Measurement at 1.5V
–
500
ps
USB
TDC
Duty Cycle
Measurement at 1.5V
45
55
%
TPERIOD
Period
Measurement at 1.5V
TPERIODAbs
Absolute Period
Measurement at 1.5V
20.48125
THIGH
USB high time
Measurement at 2.4V
8.094
10.036
ns
TLOW
USB low time
Measurement at 0.4V
7.694
9.836
ns
20.83125
20.83542
21.18542
ns
ns
TR / TF
Rise and Fall Times
Measured between 0.8V and 2.0V
1.0
2.0
V/ns
TCCJ
Cycle to Cycle Jitter
Measurement at 1.5V
–
350
ps
TLTJ
Long Term Jitter
Measurement at [email protected] us
–
TBD
ps
REF
TDC
REF Duty Cycle
Measurement at 1.5V
45
55
%
TPERIOD
REF Period
Measurement at 1.5V
69.8203
69.8622
ns
TPERIODAbs
REF Absolute Period
Measurement at 1.5V
68.82033
70.86224
ns
TR / TF
REF Rise and Fall Times
Measured between 0.8V and 2.0V
1.0
4.0
V/ns
TCCJ
REF Cycle to Cycle Jitter
Measurement at 1.5V
–
1000
ps
ENABLE/DISABLE and SET-UP
TSTABLE
Clock Stabilization from Power-up
TSS
Stopclock Set-up Time
TSH
Stopclock Hold Time
Document #: 38-07638 Rev. *C
–
1.8
ms
10.0
–
ns
0
–
ns
Page 11 of 15
CY28RS480
Test and Measurement Set-up
For PCI Single-ended Signals and Reference
The following diagram shows the test load configurations for
the single-ended PCI, USB, and REF output signals.
PCI/
USB
12Ω
60Ω
12Ω
60Ω
Measurement
Point
5pF
Measurement
Point
5pF
Measurement
Point
60Ω
22Ω
5pF
Measurement
Point
60Ω
22Ω
REF
5pF
Measurement
Point
60Ω
22Ω
5pF
Figure 4. Single-ended Load Configuration
For Differential CPU and SRC Output Signals
The following diagram shows the test load configuration for the
differential SRC outputs.
M e a s u re m e n t
P o in t
100 Ω
33Ω
SRCT
4 9 .9 Ω
2pF
M e a s u re m e n t
P o in t
100 Ω
33Ω
SRCC
IR E F
4 9 .9 Ω
2pF
475Ω
Figure 5. 0.7V Load Configuration
3 .3 V s ig n a l s
T DC
-
-
3 .3 V
2 .4 V
1 .5 V
0 .4 V
0V
TR
TF
Figure 6. Single-ended Output Signals (for AC Parameters Measurement)
Document #: 38-07638 Rev. *C
Page 12 of 15
CY28RS480
Vbias=1.25V
15 ohms
3900pF
125 ohms
125 ohms
169 ohms
15 ohms
3900pF
5pF
5pF
Figure 7. CPU Output Load Configuration
Ordering Information
Part Number
Package Type
Product Flow
Lead-free
CY28RS480OXC
56-pin SSOP
Commercial, 0° to 70°C
CY28RS480OXCT
56-pin SSOP – Tape and Reel
Commercial, 0° to 70°C
CY28RS480ZXC
56-pin TSSOP
Commercial, 0° to 70°C
CY28RS480ZXCT
56-pin TSSOP – Tape and Reel
Commercial, 0° to 70°C
Package Drawing and Dimensions
56-Lead Shrunk Small Outline Package O56
.020
1
28
0.395
0.420
0.292
0.299
29
DIMENSIONS IN INCHES MIN.
MAX.
56
0.720
0.730
SEATING PLANE
0.088
0.092
0.095
0.110
0.005
0.010
.010
GAUGE PLANE
0.025
BSC
0.110
0.008
0.0135
0.008
0.016
0°-8°
0.024
0.040
51-85062-*C
Document #: 38-07638 Rev. *C
Page 13 of 15
CY28RS480
Package Drawing and Dimensions (continued)
56-Lead Thin Shrunk Small Outline Package, Type II (6 mm x 12 mm) Z56
0.249[0.009]
28
1
DIMENSIONS IN MM[INCHES] MIN.
MAX.
REFERENCE JEDEC MO-153
7.950[0.313]
8.255[0.325]
PACKAGE WEIGHT 0.42gms
5.994[0.236]
6.198[0.244]
PART #
Z5624 STANDARD PKG.
ZZ5624 LEAD FREE PKG.
29
56
13.894[0.547]
14.097[0.555]
1.100[0.043]
MAX.
GAUGE PLANE
0.25[0.010]
0.20[0.008]
0.851[0.033]
0.950[0.037]
0.500[0.020]
BSC
0.170[0.006]
0.279[0.011]
0.051[0.002]
0.152[0.006]
0°-8°
SEATING
PLANE
0.508[0.020]
0.762[0.030]
0.100[0.003]
0.200[0.008]
51-85060-*C
Purchase of I2C components from Cypress or one of its sublicensed Associated Companies conveys a license under the Philips
I2C Patent Rights to use these components in an I2C system, provided that the system conforms to the I2C Standard Specification
as defined by Philips. ATI is a registered trademark of ATI Technologies Inc. HyperTransport is a trademark of the HyperTransport
Technology Consortium. Intel and Pentium are registered trademarks of Intel Corporation. AMD is a registered trademark of
Advanced Micro Devices, Inc. All product and company names mentioned in this document are the trademarks of their respective
holders.
Document #: 38-07638 Rev. *C
Page 14 of 15
© Cypress Semiconductor Corporation, 2005. The information contained herein is subject to change without notice. Cypress Semiconductor Corporation assumes no responsibility for the use
of any circuitry other than circuitry embodied in a Cypress product. Nor does it convey or imply any license under patent or other rights. Cypress products are not warranted nor intended to be
used for medical, life support, life saving, critical control or safety applications, unless pursuant to an express written agreement with Cypress. Furthermore, Cypress does not authorize its
products for use as critical components in life-support systems where a malfunction or failure may reasonably be expected to result in significant injury to the user. The inclusion of Cypress
products in life-support systems application implies that the manufacturer assumes all risk of such use and in doing so indemnifies Cypress against all charges.
CY28RS480
Document History Page
Document Title: CY28RS480 Clock Generator for ATI RS480 Chipset
Document Number: 38-07638
REV.
ECN NO.
Issue Date
Orig. of
Change
Description of Change
**
204582
See ECN
RGL
New data sheet
*A
215828
See ECN
RGL
Minor change: posted to external web site
*B
267850
See ECN
RGL
Changed pins 10 and 11 from internal Pull up to Pull down
Changed polarity of CLKREQ#
Added register byte 3 bits [1:3] for CPU Stop control
Changed the Slew rate to max of 6.5V/ns
Changed the IDD max load from 400 to 450 mA
Changed the IPD Outputs Driven from 70 to 75 mA
Changed the CPU Duty Cycle from 45 to 53 to 45 to 55%
Changed the HTT66 Cycle to cycle jitter from 300 to 450 ps
Fixed the Single-ended loading diagram
*C
325360
See ECN
RGL
Fixed the ordering information table to match the parts in the DevMaster
Document #: 38-07638 Rev. *C
Page 15 of 15