CYPRESS CY28343

CY28343
Zero Delay SDR/DDR Clock Buffer
Features
• External feedback pins FBIN_SDR/FBOUT_SDR are
used to synchronize the outputs to the clock input for
DDR.
• SMBus interface enables/disables outputs.
• Conforms to JEDEC SDR/DDR specifications
• Low jitter, low skew
• 48 pin SSOP package
• Phase-lock loop clock distribution for DDR and SDR
SDRAM applications
• One-single-end clock input to 6 pairs DDR outputs or
13 SDR outputs.
• External feedback pins FBIN_SDR/FBOUT_SDR are
used to synchronize the outputs to the clock input for
SDR.
Table 1. Function Table
SELDDR_SDR#
CLKIN
SDRAM(0:12)
DDRT/C(0:5)
FBIN_DDR
FBOUT_DDR
1= DDR Mode
2.5V
Compatible
OFF
Active
2.5V
Compatible
2.5V
Compatible
Active
2.5V
Compatible
OFF
OFF
0 = SDRAM Mode
3.3V
Compatible
Active
3.3V
Compatible
OFF
OFF
OFF
Active
3.3V
Compatible
Active
3.3V
Compatible
Pin Configuration[1]
Block Diagram
SCLK
Control
Logic
SDATA
FBIN_SDR FBOUT_SDR
VDD_2.5V
FBOUT_DDR
VDD_3.3V
DDRT(0:5)
DDRC(0:5)
CLKIN
VDD_3.3V
FBOUT_SDR
FBIN_DDR
PLL
*SELDDR_SDR
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
VDD_3.3V
SDRAM0
SDRAM1
SDRAM2
SDRAM3
VSS
VDD_3.3V
SDRAM4
SDRAM5
CLKIN
SDRAM6
SDRAM7
VSS
VDD_3.3V
SDRAM8
SDRAM9
SDRAM10
SDRAM11
VSS
VDD_3.3V
SDRAM12
FBOUT_SDR
FBIN_SDR*
VSS
SDRAM (0:12)
FBIN_SDR
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
SELDDR_SDR#*
FBIN_DDR*
FBOUT_DDR
VDD_2.5V
DDRT5
DDRC5
DDRT4
DDRC4
VSS
VDD_2.5
DDRT3
DDRC3
DDRT2
DDRC2
VSS
VDD_2.5V
DDRT1
DDRC1
DDRT0
DDRC0
VSS
VDD_3.3V
SCLK**
SDATA**
Note:
1. Pins marked with [*] have internal pull-down resistors. Pins marked with [**] have internal pull-up resistors.
Cypress Semiconductor Corporation
Document #: 38-07369 Rev. *A
•
3901 North First Street
•
San Jose
•
CA 95134 • 408-943-2600
Revised December 26, 2002
CY28343
Pin Description[2, 3]
Pin
Name
I/O
10
CLKIN
47
FBIN_DDR
I
PD
Feedback Clock Output. Connect to FBOUT_DDR for accessing the PLL.
See Function Table on page 1
23
FBIN_SDR
I
PD
Feedback Clock Input. Connect to FBOUT_SDR for accessing the PLL. See
Function Table on page 1
30,32,36,38
42,44
DDRT(0:5)
O
Clock Outputs. True copies of the CLKIN input
29,31,35,37
41,43
DDRC(0:5)
O
Clock Outputs. Complementary copies of the CLKIN input
2-5,8,9
15-18,21
SDRAM(0:12)
O
Clock Outputs. True copies of the CLKIN input
46
FBOUT_DDR
O
Feedback Clock Output. Connect to FBIN_DDR for normal operation. A true
copy of the CLKIN input. The delay of the PCB trace RC at this output will
control Input Reference/DDR Output Clocks phase relationships.
22
FBOUT_SDR
O
Feedback Clock Output. Connect to FBIN_SDR for normal operation. A true
copy of the CLKIN input. The delay of the PCB trace RC at this output will
control Input Reference/ SDR Output Clocks phase relationships.
48
SELDDR_SDR#
I
PD
SDR or DDR Select Pin. See Function Table on page 1
26
SCLK
I
PU
Serial Clock Input. Clocks data at SDATA into the internal register.
25
SDATA
I/O
PU
Serial Data Input. Input data is clocked to the internal register to enable/disable
individual outputs. This provides flexibility in power management.
1,7,14,20,27
VDD_3.3V
3.3V power supply for SDR outputs and two line serial Interface
33,39,45
VDD_2.5V
2.5V power supply for DDR outputs
6,13,19,24,28 VSS
,34,40
I
Description
Clock Input. Reference the PLL
Common Ground
Notes:
2. PU = internal pull-up PD = internal pull-down.
3. A bypass capacitor (0.1 mF) 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.
Power Management
Zero Delay Buffer
The individual output enable/disable control of the CY28343
allows the user to implement unique power management
schemes into the design. Outputs are in LOW state when disabled through the two-line interface as individual bits are set
LOW in Byte0 to Byte2 registers. The feedback output
FBOUT_DDR and FBOUT_SDR cannot be disabled via
two-line serial bus.
When used as a ZERO delay buffer the CY28343 will likely be
in a nested clock tree application. For these applications the
CY28343 offers single-end input as a PLL reference. The
CY28343 then can lock onto the reference and translate with
near zero to low-skew outputs. For normal operation, the external feedback input, FBIN_DDR and FBIN_SDR, are connected to the feedback output, FBOUT_DDR and
FBOUT_SDR. 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.
Document #: 38-07369 Rev. *A
Page 2 of 10
CY28343
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, etc., can be individually enabled or disabled.
The clock driver serial protocol accepts byte write, byte read,
block write, and block read operation 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 individual indexed bytes. The offset
of the indexed byte is encoded in the command code, as described in Table 2.
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 block write and block read protocol is outlined in Table 3
while Table 4 outlines the corresponding byte write and byte
read protocol.
The slave receiver address is 11010010 (D2h).
T
Table 2. Command Code Definition
Bit
7
(6:0)
Description
0 = Block read or block write operation
1 = Byte read or byte write operation
Byte offset for byte read or byte write operation. For block read or block write operations, these bits
should be ’0000000’
Table 3. Block Read and Block Write Protocol
Block Write Protocol
Bit
Block Read Protocol
Description
Bit
Description
1
Start
1
Start
2:8
Slave address – 7 bits
2:8
Slave address – 7 bits
9
Write
9
Write
10
Acknowledge from slave
10
Acknowledge from slave
11:18
Command Code – 8 Bit'00000000' stands for
block operation
11:18
Command Code – 8 Bit'00000000' stands for
block operation
19
Acknowledge from slave
19
Acknowledge from slave
20:27
Byte Count – 8 bits
20
Repeat start
28
Acknowledge from slave
21:27
Slave address – 7 bits
29:36
Data byte 0 – 8 bits
28
Read
37
Acknowledge from slave
29
Acknowledge from slave
38:45
Data byte 1 – 8 bits
30:37
Byte count from slave – 8 bits
46
Acknowledge from slave
38
Acknowledge
....
Data Byte N/Slave Acknowledge
39:46
Data byte from slave –8 bits
....
Data Byte N – 8 bits
47
Acknowledge
....
Acknowledge from slave
48:55
Data byte from slave – 8 bits
....
Stop
56
Acknowledge
....
Data bytes from slave/Acknowledge
....
Data byte N from slave – 8 bits
....
Not Acknowledge
....
Stop
Document #: 38-07369 Rev. *A
Page 3 of 10
CY28343
Table 4. Byte Read and Byte Write Protocol
Byte Write Protocol
Bit
Byte Read Protocol
Description
Bit
Description
1
Start
1
Start
2:8
Slave address – 7 bits
2:8
Slave address – 7 bits
9
Write
9
Write
10
Acknowledge from slave
10
Acknowledge from slave
11:18
Command Code - 8 bits'1xxxxxxx' stands for
11:18
byte operationbit[6:0] of the command code represents the offset of the byte to be accessed
Command Code – 8 bits'1xxxxxxx' stands for
byte operationbit[6:0] of the command code represents the offset of the byte to be accessed
19
Acknowledge from slave
19
Acknowledge from slave
20:27
Byte Count – 8 bits
20
Repeat start
28
Acknowledge from slave
21:27
Slave address – 7 bits
29
stop
28
Read
29
Acknowledge from slave
30:37
Data byte from slave – 8 bits
38
Not Acknowledge
39
stop
Byte 0: Output Register (1 = Enable, 0 = Disable)[4]
Bit
@Pup
Pin #
Description
7
1
29,30
DDRT/C0. 1 = Enable, 0 = Output disabled asynchronously in a low state
6
1
31,32
DDRT/C1. 1 = Enable, 0 = Output disabled asynchronously in a low state
5
1
35,36
DDRT/C2. 1 = Enable, 0 = Output disabled asynchronously in a low state
4
1
37,38
DDRT/C3. 1 = Enable, 0 = Output disabled asynchronously in a low state
3
1
41,42
DDRT/C4. 1 = Enable, 0 = Output disabled asynchronously in a low state
2
1
43,44
DDRT/C5. 1 = Enable, 0 = Output disabled asynchronously in a low state
1
1
0
1
Reserved
48
SELDDR_DDR hardware setting value. Read only.
Byte 1: Output Register (1 = Enable, 0 = Disable)[4]
Bit
@Pup
Pin #
Description
7
1
12
SDRAM7. 1 = Enable, 0 = Output disabled asynchronously in a low state
6
1
11
SDRAM6. 1 = Enable, 0 = Output disabled asynchronously in a low state
5
1
9
SDRAM5. 1 = Enable, 0 = Output disabled asynchronously in a low state
4
1
8
SDRAM4. 1 = Enable, 0 = Output disabled asynchronously in a low state
3
1
5
SDRAM3. 1 = Enable, 0 = Output disabled asynchronously in a low state
2
1
4
SDRAM2. 1 = Enable, 0 = Output disabled asynchronously in a low state
1
1
3
SDRAM1. 1 = Enable, 0 = Output disabled asynchronously in a low state
0
1
2
SDRAM0. 1 = Enable, 0 = Output disabled asynchronously in a low state
Note:
4. These bits will be ignored in DDR mode. See Table 1 on page 1.
Document #: 38-07369 Rev. *A
Page 4 of 10
CY28343
Byte 2: Output Register (1 = Enable, 0 = Disable)[4]
Bit
@Pup
Pin #
Description
7
1
Reserved for device test.
6
1
Select drive strength for SDR outputs. 1 = Low drive, 0 = High drive
5
1
Reserved
4
1
21
SDRAM12. 1 = Enable, 0 = Output disabled asynchronously in a low state
3
1
18
SDRAM11. 1 = Enable, 0 = Output disabled asynchronously in a low state
2
1
17
SDRAM10. 1 = Enable, 0 = Output disabled asynchronously in a low state
1
1
16
SDRAM9. 1 = Enable, 0 = Output disabled asynchronously in a low state
0
1
15
SDRAM8. 1 = Enable, 0 = Output disabled asynchronously in a low state
Byte 3: Silicon Register (Read Only)
Bit
@Pup
7
1
6
0
5
0
4
0
3
0
2
0
1
0
0
0
Pin #
Description
Vendor ID
1000 Cypress
Revision ID
Document #: 38-07369 Rev. *A
Page 5 of 10
CY28343
Maximum Ratings[5]
Operating Temperature: .................................... 0°C to +70°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:
Maximum ESD Protection:...........................................2000V
VSS < (Vin or Vout) < VDD
Maximum Power Supply: ................................................5.5V
Unused inputs must always be tied to an appropriate logic voltage level (either VSS or VDD).
Maximum Input Voltage Relative to VSS: ............. VSS – 0.5V
Maximum Input Voltage Relative to VSS: ............ VSS + 0.7V
Storage Temperature: ................................ –65°C to + 150°C
DC Parameters[6]: TA = 0°C to +70°C
Parameter
Description
Condition
Min.
Typ.
SDATA, SCLK
Max.
Unit
1.0
V
VIL
Input Low Voltage
VIH
Input High Voltage
VIL
CLKIN Input Low Voltage
(SDR Mode, VDD_3.3V = 3.3V)
CLKIN, FBIN_SDR
–0.3
0.8
V
VIL
CLKIN Input Low Voltage
(DDR Mode, VDD_2.5V = 2.5V)
CLKIN, FBIN_DDR
–0.3
0.7
V
VIH
CLKIN Input High Voltage
(SDR Mode, VDD_3.3V = 3.3V)
CLKIN, FBIN_SDR
2.0
VDD + 0.3
V
VIH
CLKIN Input High Voltage
(DDR Mode, VDD_2.5V = 2.5V)
CLKIN, FBIN_DDR
1.7
VDD + 0.3
V
IOZ
High-Impedance Output Current
VO = GND or
VO = VDD
–10
10
mA
IDDQ
Dynamic Supply Current[7]
FO = 133 MHz
300
ma
Cin
Input Pin Capacitance
2.2
V
235
4
pF
Table 5. AC Parameters for DDRT/C (0:5): VDD_2.5V = 2.5V ±5%, AVDD_3.3V = 3.3V ±5%, TA = 0°C to +70°C
Parameter
Description
Condition
Max.
Unit
99
170
MHz
55
%
53
%
1.5
ms
2.3
V/ns
fCLK
Operating Clock Frequency
tDCI
Input Clock Duty Cycle
45
tDCO
Output Clock Duty Cycle
47
tLOCK[9]
Maximum PLL Lock Time
Tr/Tf
Output Clocks Slew Rate
tpZL, tpZH
Output Enable
3
5
ns
outputs)
3
5
ns
90
125
ps
200
ps
150
ps
VDD – 0.4
V
(VDD/2) + 0.2
V
Half-Period Jitter
tPHASE
Phase Error
Vx
1.0
outputs)
tHPJ
@100 MHz and 133 MHz
@133 MHz
Any Output to Any Output
Output Voltage
50
[8](all
Output Disable Time
VOUT
20% to 80% of VDD_2.5V
Typ.
Time[8](all
tpLZ, tpHZ
tSKEW
VDD_2.5V = 2.5V ±5%
Min.
Skew[7]
Swing[7]
Output Crossing
Voltage[7]
1.1
(VDD/2) – 0.2
VDD/2
Notes:
5. 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.
6. Unused inputs must be held high or low to prevent them from floating.
7. All differential output terminals are terminated with 120Ω/16 pF as shown in Figure 4.
8. Refers to the transition of non-inverting output.
9. Time required for the integrated PL circuit to obtain phase lock of its feed back signal to its reference signal. For Phase lock specifications for propagation delay,
skew and jitter parameters given in the switching characteristics table are not applicable.
Document #: 38-07369 Rev. *A
Page 6 of 10
CY28343
Table 6. AC Parameters for SDRAM Outputs: VDD_3.3V = 2.5V ±5%, AVDD_3.3V = 3.3V ±5%, TA = 0°C to +70°C
Parameter
Description
Condition
fCLK
Operating Clock Frequency
tDCI
Input Clock Duty Cycle
tLOCK[9]
Maximum PLL Lock Time
tDCO
Output Clock Duty Cycle
Tr/Tf
[10, 11,
12]
Min
VDD_3.3V = 3.3V ±5%
100 MHz, 133 MHz
Output Clocks Slew Rate
Max
Unit
99
133
MHz
45
55
%
1.5
ms
55
%
1.6
ps
45
Typ
50
0.4
tpZL, tpZH
Output Enable Time (all outputs)
3
5
ns
tpLZ, tpHZ
Output Disable Time (all outputs)
3
5
ns
tCCJ
Cycle-to-Cycle Jitter
@133 MHz
90
200
ps
tPHASE
Phase Error
@133 MHz
400
ps
tSKEW
Any Output to Any Output Skew[11]
200
ps
VDD – 0.4
V
VOUT
Output Voltage
Swing[11]
1.1
[11]
(VDD/2) – 0.2 VDD/2 (VDD/2) +
Vx
Output Crossing Voltage
Notes:
10. The tSKEW specification is only valid for equal loading of all outputs (30 pF lump-load). Measurement are acquired at 1.5V for 3.3V signals.
11. The test load is 30 pF lump-load.
12. TR/TF are measured at 0.4V to 2.4V.
0.2
V
Differential Parameter Measurement Information
1.25V /1.5V
1.25V
C K _IN
1.25V /1.5 V
1.2 5V
F B IN
t (∅ ) n+1
t (∅ ) n
=
t (∅ ) n =
Σ n1 N
t( ∅ )n
( N is large num ber o f sam ples)
N
Figure 1. Phase Error
Document #: 38-07369 Rev. *A
Page 7 of 10
CY28343
DDRCX
DDRTX
DDRCX
DDRTX
ts k (o )
Figure 2. Output Skew
DDRCx
tc (n )
DDRTx
t c (n + 1 )
t jit (c c ) = t c ( n )- t c (n + 1 )
Figure 3. Cycle-to-Cycle Jitter
TPCB
Measurement Point
DDRT
2 pF
120Ω
DDRC
TPCB
Measurement Point
2 pF
Figure 4. Differential Signal Using Direct Terminal Resistor
Document #: 38-07369 Rev. *A
Page 8 of 10
CY28343
Ordering Information
Part Number
Package Type
Product Flow
CY28343OC
48-pin SSOP
Commercial, 0° to 70°C
CY28343OCT
48-pin SSOP - Tape and Reel
Commercial, 0° to 70°C
Package Drawing and Dimensions
48-Lead Shrunk Small Outline Package O48
51-85061-C
All product and company names mentioned in this document may be the trademarks of their respective owners.
Document #: 38-07369 Rev. *A
Page 9 of 10
© 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.
CY28343
Document Title:CY28343 Zero Delay SDR/DDR Clock Buffer
Document #: 38-07369
Rev.
ECN No.
Issue
Date
Orig. of
Change
**
116671
08/22/02
DMG
*A
122909
12/26/02
RBI
Document #: 38-07369 Rev. *A
Description of Change
New Data Sheet
Add power up requirements to maximum ratings information
Page 10 of 10