W256H Cypress Semiconductor Corp, W256H Datasheet - Page 2

• Manufacturer Part Number: W256H
• Description: IC CLK BUFF 12OUT SDRAM 28SSOP
• Manufacturer: Cypress Semiconductor Corp
• Type: Fanout Buffer (Distribution)r

Specifications of W256H

• Number Of Circuits: 1
• Ratio - Input:output: 1:12
• Differential - Input:output: No/No
• Input: DDR, SDRAM
• Output: DDR, SDRAM
• Frequency - Max: 180MHz
• Voltage - Supply: 2.375 V ~ 3.465 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 28-SSOP
• Frequency-max: 180MHz
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 428-1399

Document #: 38-07256 Rev. *C
Pin Summary
SEL_DDR
SCLK
SDATA
BUF_IN
FBOUT
PWR_DWN#
DDR[0:5]T_SDRAM
[0,2,4,6,8,10]
DDR[0:5]C_SDRAM
[1,3,5,7,9, 11]
VDD3.3_2.5
GND
Name
28
16
15
10
1
2
3, 7, 12, 19, 23, 27
4, 8, 13, 18, 22, 26
5, 9, 14, 21, 25
6, 11, 17, 20, 24
Pins
Input to configure for DDR-ONLY mode or STANDARD SDRAM mode.
1 = DDR-ONLY mode.
0 = STANDARD SDRAM mode.
When SEL_DDR is pulled HIGH or configured for DDR-ONLY mode, all the buffers
will be configured as DDR outputs.
Connect VDD3.3_2.5 to a 2.5V power supply in DDR-ONLY mode.
When SEL_DDR is pulled LOW or configured for STANDARD SDRAM output, all
the buffers will be configured as STANDARD SDRAM outputs.
Connect VDD3.3_2.5 to a 3.3V power supply in STANDARD SDRAM mode.
SMBus clock input.
SMBus data input.
Reference input from chipset. 2.5V input for DDR-ONLY mode; 3.3V input for
STANDARD SDRAM mode.
Feedback clock for chipset. Output voltage depends on VDD3.3_2.5V.
Active LOW input to enable Power Down mode; all outputs will be pulled LOW.
Clock outputs. These outputs provide copies of BUF_IN. Voltage swing depends
on VDD3.3_2.5 power supply.
Clock outputs. These outputs provide complementary copies of BUF_IN when
SEL_DDR is active. These outputs provide copies of BUF_IN when SEL_DDR is
inactive. Voltage swing depends on VDD3.3_2.5 power supply.
Connect to 2.5V power supply when W256 is configured for DDR-ONLY mode.
Connect to 3.3V power supply, when W256 is configured for standard SDRAM
mode.
Ground.
Description
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W256