CY2318ANZ
18 Output, 3.3V SDRAM Buffer for
Desktop PCs with 4 DIMMs
Features
Functional Description
• One input to 18 output buffer/driver
• Supports up to four SDRAM DIMMs
• Two additional outputs for feedback
• Serial interface for individual output control
• 150ps typical output-output skew
• Up to 100 MHz operation
• Dedicated OE pin for testing
The CY2318ANZ is a 3.3V buffer designed to distribute
high-speed clocks in PC applications. The part has 18 outputs,
16 of which can be used to drive up to four SDRAM DIMMs,
and the remaining can be used for external feedback to a PLL.
The device operates at 3.3V and outputs can run up to 100
MHz, thus making it compatible with Pentium II® processors.
The CY2318ANZ can be used in conjunction with the CY2280,
CY2281, CY2282 or similar clock synthesizer for a complete
Pentium II motherboard solution.
The CY2318ANZ also includes a serial interface which can
enable or disable each output clock. On power-up, all output
clocks are enabled (internal pull up). A separate Output
Enable pin facilitates testing on ATE.
• Space-saving 48-pin SSOP package
• 3.3V operation
Pin Configuration
Block Diagram
SSOP
Top View
NC
NC
VDD
SDRAM0
SDRAM1
VSS
VDD
SDRAM2
SDRAM3
VSS
BUF_IN
VDD
SDRAM4
SDRAM5
VSS
VDD
SDRAM6
SDRAM7
VSS
VDD
SDRAM16
VSS
VDDIIC
SDATA
BUF_IN
SDRAM0
SDRAM1
SDRAM2
SDRAM3
SDRAM4
SDRAM5
SDRAM6
SDRAM7
SDRAM8
SDRAM9
SDRAM10
SDRAM11
SDATA
Serial Interface
Decoding
SCLOCK
SDRAM12
SDRAM13
SDRAM14
SDRAM15
SDRAM16
SDRAM17
OE
Cypress Semiconductor Corporation
Document #: 38-07181 Rev. *C
•
3901 North First Street
•
1
2
48
47
3
4
46
45
5
44
6
43
7
42
8
9
41
40
10
39
11
38
12
37
13
36
14
35
15
34
16
33
17
18
32
31
19
30
20
21
29
28
22
27
23
26
24
25
NC
NC
VDD
SDRAM15
SDRAM14
VSS
VDD
SDRAM13
SDRAM12
VSS
OE
VDD
SDRAM11
SDRAM10
VSS
VDD
SDRAM9
SDRAM8
VSS
VDD
SDRAM17
VSS
VSSIIC
SCLOCK
San Jose, CA 95134
•
408-943-2600
Revised Oct. 03, 2005
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CY2318ANZ
Pin Summary
Name
Pins
Description
VDD
3, 7, 12, 16, 20, 29, 33, 37, 42, 46
VSS
6, 10, 15, 19, 22, 27, 30, 34, 39, 43 Ground
VDDIIC
23
Serial interface voltage supply
VSSIIC
26
Ground for serial interface
BUF_IN
11
Input clock (5V Tolerant)
OE
38
Output Enable (active HIGH), Three-state outputs when low[1]
SDATA
24
Serial data input[1]
SCLK
25
Serial clock input[1]
SDRAM [0–3]
4, 5, 8, 9
SDRAM byte 0 clock outputs
SDRAM [4–7]
13, 14, 17, 18
SDRAM byte 1 clock outputs
SDRAM [8–11]
31, 32, 35, 36
SDRAM byte 2 clock outputs
SDRAM [12–15] 40, 41, 44, 45
SDRAM byte 3 clock outputs
SDRAM [16–17] 21, 28
SDRAM clock outputs usable for feedback
N/C
Reserved for future modifications, do not connect in system
1, 2, 47, 48
3.3V Digital voltage supply
Note:
1. Internal pull-up resistor to VDD (value > 100 kohms)
Device Functionality
OE
SDRAM [0–17]
0
Hi-Z
1
1 x BUF_IN
Document #: 38-07181 Rev. *C
Page 2 of 9
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CY2318ANZ
Serial Configuration Map
• The Serial bits will be read by the clock driver in the following
order:
Byte 0 - Bits 7, 6, 5, 4, 3, 2, 1, 0
Byte 1 - Bits 7, 6, 5, 4, 3, 2, 1, 0
.
.
Byte N - Bits 7, 6, 5, 4, 3, 2, 1, 0
• Reserved and unused bits should be programmed to “0”.
• Serial interface address for the CY2318ANZ is:
•
•
A6
A5
A4
A3
A2
A1
A0
R/W
1
1
0
1
0
0
1
----
•
Byte 1: SDRAM Active/Inactive Register
(1 = Active, 0 = Inactive), Default = Active
Bit
Pin #
Description
Bit 7
45
SDRAM15 (Active/Inactive)
Bit 6
44
SDRAM14 (Active/Inactive)
Bit 5
41
SDRAM13 (Active/Inactive)
Bit 4
40
SDRAM12 (Active/Inactive)
Bit 3
36
SDRAM11 (Active/Inactive)
Bit 2
35
SDRAM10 (Active/Inactive)
Bit 1
32
SDRAM9 (Active/Inactive)
Bit 0
31
SDRAM8 (Active/Inactive)
Byte 2: SDRAM Active/Inactive Register
(1 = Active, 0 = Inactive), Default = Active
•
Byte 0:SDRAM Active/Inactive Register
(1 = Active, 0 = Inactive), Default = Active
Bit
Pin #
Description
Bit 7 18
SDRAM7 (Active/Inactive)
Bit 6 17
SDRAM6 (Active/Inactive)
Bit 5 14
SDRAM5 (Active/Inactive)
Bit 4 13
SDRAM4 (Active/Inactive)
Bit 3 9
SDRAM3 (Active/Inactive)
Bit 2 8
SDRAM2 (Active/Inactive)
Bit 1 5
SDRAM1 (Active/Inactive)
Bit 0 4
SDRAM0 (Active/Inactive)
Document #: 38-07181 Rev. *C
Bit
Pin #
Description
Bit 7
28
SDRAM17 (Active/Inactive)
Bit 6
21
SDRAM16 (Active/Inactive)
Bit 5
--
Reserved, drive to 0
Bit 4
--
Reserved, drive to 0
Bit 3
--
Reserved, drive to 0
Bit 2
--
Reserved, drive to 0
Bit 1
--
Reserved, drive to 0
Bit 0
--
Reserved, drive to 0
Page 3 of 9
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CY2318ANZ
Maximum Ratings
Storage Temperature .................................. –65°C to +150°C
Supply Voltage to Ground Potential ..................–0.5 to +7.0V
DC Input Voltage (except BUF_IN) .......... –0.5V to VDD + 0.5
Junction Temperature ............................................... +150°C
Static Discharge Voltage............................................ >2000V
(per MIL-STD-883, Method 3015)
DC Input Voltage (BUF_IN).............................. –0.5V to 7.0V
Operating Conditions
Parameter
Description
Min.
Max.
Unit
VDD, VDDIIC
Supply Voltage
3.135
3.465
V
TA
Operating Temperature (Ambient Temperature)
0
70
°C
CL
Load Capacitance
20
30
pF
CIN
Input Capacitance
7
pF
tPU
Power-up time for all VDDs to reach minimum specified voltage
(power ramps must be monotonic)
0.05
50
ms
Min.
Max.
Unit
For all pins except serial
interface pins
0.8
V
For serial pins only
0.7
V
10
µA
100
µA
10
µA
0.4
V
Electrical Characteristics Over the Operating Range
Parameter
Description
Voltage[2]
VIL
Input LOW
VILiic
Input LOW Voltage
Test Conditions
Voltage[2]
VIH
Input HIGH
IIL
Input LOW Current
(BUF_IN input)
VIN = 0V
IIL
Input LOW Current
(Except BUF_IN Pin)
VIN = 0V
IIH
Input HIGH Current
VIN = VDD
Voltage[3]
VOL
Output LOW
VOH
Output HIGH Voltage[3]
Current[3]
IDD
Supply
IDD
Supply Current
Current[3]
2.0
–10
–10
IOL = 25 mA
IOH = –36 mA
V
2.4
V
Unloaded outputs, 100 MHz
200
mA
Loaded outputs, 100 MHz
360
mA
IDD
Supply
Unloaded outputs, 66.67 MHz
150
mA
IDD
Supply Current
Loaded outputs, 66.67 MHz
230
mA
IDDS
Supply Current
BUF_IN = VDD or VSS,
all other inputs at VDD
500
µA
Notes:
2. BUF_IN input has a threshold voltage of VDD/2.
3. Parameter is guaranteed by design and characterization. Not 100% tested in production.
Document #: 38-07181 Rev. *C
Page 4 of 9
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CY2318ANZ
Switching Characteristics[4]
Parameter
Name
Test Conditions
Min.
Typ.
Maximum Operating Frequency
Duty Cycle
[3, 5]
= t2 ÷ t1
t3
Rising Edge Rate[3]
t4
Falling Edge Rate[3]
[3]
Output to Output Skew
t5
Max.
Unit
100
MHz
Measured at 1.5V
45.0
50.0
55.0
%
Measured between 0.4V and 2.4V
0.9
1.5
4.0
V/ns
Measured between 2.4V and 0.4V
0.9
1.5
4.0
V/ns
150
250
ps
All outputs equally loaded
t6
[3]
SDRAM Buffer LH Prop. Delay
Input edge greater than 1 V/ns
1.0
3.5
5.0
ns
t7
SDRAM Buffer HL Prop. Delay[3]
Input edge greater than 1 V/ns
1.0
3.5
5.0
ns
[3]
Input edge greater than 1 V/ns
1.0
5
12
ns
[3]
Input edge greater than 1 V/ns
1.0
20
30
ns
SDRAM Buffer Enable Delay
t8
SDRAM Buffer Disable Delay
t9
Switching Waveforms
Duty Cycle Timing
t1
t2
1.5V
1.5V
1.5V
All Outputs Rise/Fall Time
OUTPUT
2.4V
0.4V
2.4V
0.4V
3.3V
0V
t4
t3
Output-Output Skew
OUTPUT
1.5V
1.5V
OUTPUT
t5
Notes:
4. All parameters specified with loaded outputs.
5. Duty cycle of input clock is 50%. Rising and falling edge rate is greater than 1 V/ns.
Document #: 38-07181 Rev. *C
Page 5 of 9
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CY2318ANZ
Switching Waveforms (continued)
SDRAM Buffer LH and HL Propagation Delay
INPUT
OUTPUT
t6
t7
SDRAM Buffer Enable and Disable Times
OE
Three-State
Active
OUTPUTS
t8
t9
Test Circuit
VDD
0.1 µF
OUTPUTS
CLK out
CLOAD
GND
Document #: 38-07181 Rev. *C
Page 6 of 9
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CY2318ANZ
Application Circuit
+3.3V
Rs
CPUCLK
VDD
BUF_IN
VDDIIC
0.1 µF
0.1 µF
CY2280: 48-pin SSOP
Rs
SDRAM[0:17]
SDRAM[0:17]
Ct
SDATA
SCLK
VssIIC
Vss
CY2318ANZ: 48-pin SSOP
Rs = Series termination resistor
Ct = Optional cap to reduce EMI
Ordering Information
Ordering Code
Package Type
Operating
Range
CY2318ANZPVC–11
48-pin SSOP
Commercial
CY2318ANZPVC–11T
48-pin SSOP - Tape and Reel
Commercial
CY2318ANZPVXC–11
48-pin SSOP
Commercial
CY2318ANZPVXC–11T
48-pin SSOP- Tape and Reel
Commercial
Lead-free
Document #: 38-07181 Rev. *C
Page 7 of 9
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CY2318ANZ
Package Diagram
48-Lead Shrunk Small Outline Package O48
51-85061-*C
Pentium II is a registered trademark of Intel Corporation. All products and company names mentioned in this document may be
the trademarks of their respective holders.
Document #: 38-07181 Rev. *C
Page 8 of 9
© 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.
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CY2318ANZ
Document History Page
Document Title: CY2318ANZ 18 Output, 3.3V SDRAM Buffer for Desktop PCs with 4 DIMMs
Document Number: 38-07181
REV.
ECN NO.
Issue
Date
Orig. of
Change
Description of Change
**
111857
12/09/01
DSG
Change from Spec number: 38-00771 to 38-07181
*A
121833
12/14/02
RBI
Power up requirements added to Operating Conditions Information
*B
310577
See ECN
RGL
Added Tape and Reel option
Added Lead-free Devices
*C
399949
See ECN
RGL
Minor Change: Corrected the ordering code for the lead-free devices to match
the devmaster
Document #: 38-07181 Rev. *C
Page 9 of 9
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