CYPRESS CY28358OC

58
PRELIMINARY
CY28358
200-MHz Differential Clock Buffer/Driver
Features
Description
• Up to 200 MHz operation
• Phase-locked loop clock distribution for Double Data
Rate Synchronous DRAM applications
• Distributes one clock input to six differential outputs
• External feedback pin FBIN is used to synchronize the
outputs to the clock input
• Conforms to the DDR1 specification
• Spread Aware™ for EMI reduction
• 28-pin SSOP package
This PLL clock buffer is designed for 2.5 VDD and 2.5 AVDD
operation and differential output levels.
This device is a zero delay buffer that distributes a clock input
CLKIN to six differential pairs of clock outputs (CLKT[0:5],
CLKC[0:5]) and one feedback clock output FBOUT. The clock
outputs are controlled by the input clock CLKIN and the feedback clock FBIN.
The two line serial bus can set each output clock pair
(CLKT[0:5], CLKC[0:5]) to the Hi-Z state. When AVDD is
grounded, the PLL is turned off and bypassed for test purposes.
The PLL in this device uses the input clock CLKIN and the
feedback clock FBIN to provide high-performance, low-skew,
low–jitter output differential clocks.
Block Diagram
Pin Configuration
CLKT0
CLKC0
CLKT1
CLKC1
SCLK
SDATA
Serial
Interface
Logic
CLKIN
PLL
CLKT2
CLKC2
CLKC1
GND
SCLK
CLKT3
CLKC3
CLKIN
NC
CLKT4
CLKC4
AVDD
CLKT5
CLKC5
FBIN
CLKC0
CLKT0
VDD
CLKT1
AGND
VDD
CLKT2
CLKC2
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
CY28358
10
GND
CLKC5
CLKT5
CLKC4
CLKT4
VDD
SDATA
NC
FBIN
FBOUT
NC
CLKT3
CLKC3
GND
FBOUT
AVDD
28 pin SSOP
Cypress Semiconductor Corporation
Document #: 38-07417 Rev. *A
•
3901 North First Street
•
San Jose
•
CA 95134 • 408-943-2600
Revised December 14, 2002
CY28358
PRELIMINARY
Pin Description[1]
Pin
Name
I/O
Description
Electrical Characteristics
8
CLKIN
I
Clock Input.
Input
20
FBIN
I
Feedback Clock Input. Connect to FBOUT for
accessing the PLL.
Input
Differential Outputs
2,4,13,17,24,26
CLKT(0:5)
O
Clock Outputs
1,5,14,16,25,27
CLKC(0:5)
O
Clock Outputs
19
FBOUT
O
Feedback Clock Output. Connect to FBIN for
normal operation. A bypass delay capacitor at
this output will control Input Reference/Output
Clocks phase relationships.
Output
7
SCLK
I
Serial Clock Input. Clocks data at SDATA into
the internal register.
Data Input for the two line serial bus
22
SDATA
I/O
Serial Data Input. Input data is clocked to the
internal register to enable/disable individual
outputs. This provides flexibility in power
management.
Data Input and Output for the two line
serial bus
3,12,23
VDD
2.5V Power Supply for Logic
2.5V Nominal
10
AVDD
2.5V Power Supply for PLL
2.5V Nominal
6,15,28
GND
Ground
11
AGND
Analog Ground for PLL
9, 18, 21
NC
Not Connected
Function Table
Inputs
Outputs
PLL
CLKIN
CLKT(0:5)[2]
CLKC(0:5)[2]
FBOUT
GND
L
L
H
L
GND
H
H
L
H
BYPASSED/OFF
2.5V
L
L
H
L
On
VDDA
BYPASSED/OFF
2.5V
H
H
L
H
On
2.5V
< 20 MHz
Hi-Z
Hi-Z
Hi-Z
Off
Zero Delay Buffer
When used as a zero delay buffer the CY28358 will likely be
in a nested clock tree application. For these applications the
CY28358 offers a clock input as a PLL reference. The
CY28358 then can lock onto the reference and translate with
near zero delay to low-skew outputs. For normal operation, the
external feedback input, FBIN, is connected to the feedback
output, FBOUT. By connecting the feedback output to the
feedback input the propagation delay through the device is
eliminated. The PLL works to align the output edge with the
input reference edge thus producing a near zero delay. The
reference frequency affects the static phase offset of the PLL
and thus the relative delay between the inputs and outputs.
When VDDA is strapped LOW, the PLL is turned off and bypassed for test purposes.
Power Management
The individual output enable/disable control of the CY28358
allows the user to implement unique power management
schemes into the design. Outputs are three-stated when disabled through the two-line interface as individual bits are set
low in Byte0 and Byte1 registers. The feedback output FBOUT
cannot be disabled via two line serial bus. The enabling and
disabling of individual outputs is done in such a manner as to
eliminate the possibility of partial “runt” clocks.
Notes:
1. A bypass capacitor (0.1µF) should be placed as close as possible to each positive power pin (<0.2”). If these bypass capacitors are not close to the pins their
high frequency filtering characteristic will be cancelled by the lead inductance of the traces.
2. Each output pair can be three-stated via the two line serial interface.
Document #: 38-07417 Rev. *A
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CY28358
PRELIMINARY
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 initialize 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 can also be used during system operation for
power management functions.
The clock driver serial protocol accepts 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. The
block write and block read protocol is outlined in Table 1. The
slave receiver address is 11010010 (D2h).
T
Table 1. Block Read and Block Write Protocol
Block Write Protocol
Bit
1
2:8
Description
Start
Slave address – 7 bits
Block Read Protocol
Bit
1
2:8
Description
Start
Slave address – 7 bits
9
Write = 0
9
Write = 0
10
Acknowledge from slave
10
Acknowledge from slave
11:18
19
20:27
28
29:36
37
38:45
Command Code – 8 bits
'00000000' stands for block operation
11:18
Command Code – 8 bits
'00000000' stands for block operation
Acknowledge from slave
19
Acknowledge from slave
Byte Count – 8 bits
20
Repeat start
Acknowledge from slave
21:27
Slave address – 7 bits
Data byte 1 – 8 bits
28
Read = 1
Acknowledge from slave
29
Acknowledge from slave
Data byte 2 – 8 bits
30:37
46
Acknowledge from slave
....
......................
....
Data Byte (N–1) – 8 bits
47
....
Acknowledge from slave
48:55
....
Data Byte N – 8 bits
56
Acknowledge
....
Acknowledge from slave
....
Data bytes from slave/Acknowledge
....
Stop
....
Data byte N from slave – 8 bits
....
Not Acknowledge
....
Stop
Document #: 38-07417 Rev. *A
38
Byte count from slave – 8 bits
39:46
Acknowledge
Data byte from slave – 8 bits
Acknowledge
Data byte from slave – 8 bits
Page 3 of 11
CY28358
PRELIMINARY
Byte0: Output Register1 (1 = Enable, 0 = Disable)
Bit
@Pup
Pin#
Description
7
1
2, 1
CLKT0, CLKC0
6
1
4, 5
CLKT1, CLKC1
5
1
Reserved
4
1
Reserved
3
1
13, 14
CLKT2, CLKC2
2
1
26, 27
CLKT5, CLKC5
1
1
0
1
24, 25
CLKT4, CLKC4
Reserved
Byte1: Output Register 2 (1 = Enable, 0 = Disable)
Bit
@Pup
Pin#
Description
7
1
6
1
5
0
Reserved
4
0
Reserved
3
0
Reserved
2
0
Reserved
1
0
Reserved
0
0
Reserved
Reserved
17, 16
CLKT3, CLKC3
Byte2: Test Register 3
Bit
@Pup
7
1
Reserved
6
1
Reserved
5
1
Reserved
4
1
Reserved
3
1
Reserved
2
1
Reserved
1
1
Reserved
0
1
Reserved
Document #: 38-07417 Rev. *A
Pin#
Description
Page 4 of 11
CY28358
PRELIMINARY
Parameter Measurement Information
CLKIN
1.25V
1.25V
FBIN
1.25V
1.25V
t(∅)n+1
t(∅)n
t(∅)n =
Σ n1=N
N
t(∅)n
(N is large number of samples)
Figure 1. Static Phase Offset
CLKIN
1.25V
1.25V
FBIN
td(∅)
t(∅)
td(∅)
td(∅)
t(∅ )
td(∅)
Figure 2. Dynamic Phase Offset
CLKT[0:5], FBOUT
CLKC[0:5]
CLKT[0:5], FBOUT
CLKC[0:5]
tsk(o)
Figure 3. Output Skew
Document #: 38-07417 Rev. *A
Page 5 of 11
CY28358
PRELIMINARY
CLKT[0:5], FBOUT
CLKC[0:5]
tc(n)
CLKT[0:5], FBOUT
CLKC[0:5]
1
f(o)
tjit(hper) = tc(n) - 1
fo
Figure 4. Period Jitter
CLKT[0:5], FBOUT
CLKC[0:5]
t(hper_N+1)
t(hper_n)
1
f(o)
t jit(hper) = thper(n) - 1
2x fo
Figure 5. Half-Period Jitter
CLKT[0:5], FBOUT
CLKC[0:5]
t c(n)
t c(n)
t jit(cc) = t c(n) - t c(n+1)
Figure 6. Cycle-to-cycle Jitter
Document #: 38-07417 Rev. *A
Page 6 of 11
CY28358
PRELIMINARY
T PCB
M easurem ent Point
CLKT
16 pF
CLKIN
100 Ω
50 Ω
CLKC
T PCB
M easurem ent Point
16 pF
FBIN
FBOUT
50 Ω
Figure 7. Differential Signal Using Direct Termination Resistor
Document #: 38-07417 Rev. *A
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CY28358
PRELIMINARY
Maximum Ratings[3]
Storage Temperature: ................................ –65°C to + 150°C
This device contains circuitry to protect the inputs against
damage due to high static voltages or electric field; however,
precautions should be taken to avoid application of any voltage higher than the maximum rated voltages to this circuit. For
proper operation, Vin and Vout should be constrained to the
range:
Operating Temperature: .................................... 0°C to +85°C
VSS < (Vin or Vout) < VDD
Maximum Power Supply: ................................................3.5V
Unused inputs must always be tied to an appropriate logic voltage level (either VSS or VDD).
Input Voltage Relative to VSS:...............................VSS – 0.3V
Input Voltage Relative to VDDQ or AVDD:.............. VDD + 0.3V
DC Parameters[4] (VDDA = VDDQ = 2.5V + 5%, TA = 0°C to +70°C)
Parameter
Description
Conditions
Min.
VIL
Input Low Voltage
SDATA, SCLK
VIH
Input High Voltage
SDATA, SCLK
VIL
Input Voltage Low
CLKIN, FBIN
VIH
Input Voltage High
CLKIN, FBIN
2.1
IIN
Input Current
VIN = 0V or VIN = VDDQ, CLKIN,
FBIN
–10
Typ.
Max.
Unit
1.0
V
2.2
V
0.4
V
V
10
µA
IOL
Output Low Current
VDDQ = 2.375V, VOUT = 1.2V
26
35
mA
IOH
Output High Current
VDDQ = 2.375V, VOUT = 1V
–18
–32
mA
VOL
Output Low Voltage
VDDQ = 2.375V, IOL = 12 mA
VOH
Output High Voltage
VDDQ = 2.375V, IOH = –12 mA
VOUT
Output Voltage
Swing[5}
VOC
Output Crossing
Voltage[6]
IOZ
High-Impedance
Output Current
VO = GND or VO = VDDQ
IDDQ
Dynamic Supply
Current[7]
All VDDQ and VDDI,
FO = 200 MHz
IDSTAT
Static Supply Current
IDD
PLL Supply Current
CIN
Input Pin Capacitance
0.6
V
1.1
(VDDQ/2) –
0.2
VDDA only
V
1.7
VDDQ–0.4
V
(VDDQ/2) + 0.2
V
10
µA
235
300
mA
2
mA
9
12
mA
4
6
pF
VDDQ/2
–10
Notes:
3. 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.
4. Unused inputs must be held high or low to prevent them from floating
5. For load conditions see Figure 7.
6. The value of VOC is expected to be |VTR + VCP|/2. In case of each clock directly terminated by a 120Ω resistor. See Figure 7.
7. All outputs switching loaded with 16pF in 60Ω environment. SeeFigure 7
Document #: 38-07417 Rev. *A
Page 8 of 11
CY28358
PRELIMINARY
AC Parameters[8,9] (VDD = VDDQ = 2.5V±5%, TA = 0°C to +70°C)
Parameter
Description
Conditions
Min.
fCLK
Operating Clock Frequency
60
tDC
Input Clock Duty Cycle
40
tLOCK
Maximum PLL lock Time
1
Max.
Unit
200
MHz
60
%
100
µs
2.5
V/ns
tR/tF
Output Clocks Slew Rate
tPZL,tPZH
Output Enable Time[10]
(all outputs)
3
ns
tPLZ,tPHZ
Output Disable Time[10]
(all outputs)
3
ns
tCCJ
Cycle to Cycle Jitter[12]
jitter[12]
20% to 80% of VOD
Typ.
f > 66 MHz
–100
f > 66 MHz
–100
100
ps
tjit(h-per)
Half-period
100
ps
tPLH
Low-to-High Propagation Delay, CLKIN
to CLKT[0:5]
1.5
3.5
6
ns
tPHL
High-to-Low Propagation Delay, CLKIN
to CLKT[0:5]
1.5
3.5
6
ns
tSKEW
Any Output to Any Output Skew[11]
100
ps
–150
150
ps
–50
50
ps
Error[11]
tPHASE
Phase
tPHASEJ
Phase Error Jitter
f > 66 MHz
Notes:
8. Parameters are guaranteed by design and characterization. Not 100% tested in production.
9. PLL is capable of meeting the specified parameters while supporting SSC synthesizers with modulation frequency between 30kHz and 33.3kHz with a down
spread of –0.5%.
10. Refers to transition of non-inverting outpu.t
11. All differential input and output terminals are terminated with 120Ω/16pF as shown in Figure 7.
12. Period Jitter and Half-Period Jitter specifications are separate specifications that must be met independently of each other.
Document #: 38-07417 Rev. *A
Page 9 of 11
PRELIMINARY
CY28358
Ordering Information
Part Number
CY28358OC
CY28358OCT
Package Type
Product Flow
28-Pin SSOP
Commercial, 0° to 70°C
28-Pin SSOP -Tape and Reel
Commercial, 0° to 70°C
Package Drawing and Dimensions
28-Lead (5.3 mm) Shrunk Small Outline Package O28
51-85079-*C
Spread Aware is a trademark of Cypress Semiconductor Corporation. All product and company names mentioned in this document
may be the trademarks of their respective holders.
Document #: 38-07417 Rev. *A
Page 10 of 11
© Cypress Semiconductor Corporation, 2002. 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 Semiconductor product. Nor does it convey or imply any license under patent or other rights. Cypress Semiconductor 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
Semiconductor products in life-support systems application implies that the manufacturer assumes all risk of such use and in doing so indemnifies Cypress Semiconductor against all charges..
CY28358
PRELIMINARY
Document History Page
Document Title: CY28358 200-MHz Differential Clock Buffer/Driver
Document #: 38-07417
REV.
ECN NO.
Issue
Date
Orig. of
Change
**
118004
09/11/02
INA
New Data Sheet
*A
122925
12/14/02
RBI
Add power up requirements to operating condicitons information.
Document #: 38-07417 Rev. *A
Description of Change
Page 11 of 11