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Details, datasheet, quote on part number:W311H
 
 
Part:W311H
Category:Timing Circuits => Clock Generators => Motherboard
Description:Frequency Timing Generators For PC And Server Motherboards
Company:Cypress Semiconductor Corp.
Datasheet:Download W311H datasheet   File size : 392 kB
Request For quote:  Find where to buy W311H
 



Datasheet text preview:
1W 311
Preliminary
W311
FTG for VIA Pro-266 DDR Chipset
Features
· Maximized EMI Suppression using Cypress's Spread Spectrum Technology · System frequency synthesizer for VIA Pro-2000 · Programmable clock output frequency with less than 1 MHz increment · Integrated fail-safe Watchdog Timer for system recovery · Automatically switch to HW selected or SW programmed clock frequency when Watchdog Timer time-out · Capable of generate system RESET after a Watchdog Timer time-out occurs or a change in output frequency via SMBus interface · Support SMBus byte read/write and block read/ write operations to simplify system BIOS development · Vendor ID and Revision ID support · Programmable drive strength for CPU and PCI output clocks · Programmable output skew between CPU, AGP and PCI · Supports Intel® Celeron® and Pentium® III class processor · Three copies of CPU output · Nine copies of PCI output · One 48-MHz output for USB · One 24-MHz or 48-MHz output for SIO · Two buffered reference outputs · Three copies of APIC output · Supports frequencies up to 200 MHz · SMBus interface for programming · Power management control inputs · Available in 48-pin SSOP Key Specifications CPU Cycle-to-Cycle Jitter:..........250 ps CPU to CPU Output Skew:.........175 ps PCI Cycle to Cycle Jitter:............500 ps PCI to PCI Output Skew: ............ 500 ps
Block Diagram
VDD _R EF R EF0 X1 X2 X TA L OSC
PLL Ref Freq
Pin Configuration[1]
VD D_ REF GN D_ REF X1 X2 VDD_48 MHz FS3*/48 MHz FS2*/24_48 MHz GND_48 MHz PCI_F PCI 1 PCI 2 GND_PCI PCI 3 PCI 4 VDD_PCI PCI 5 PCI 6 PCI 7 GND_PCI PCI 8 *FS1 *FS0 AG P0 VDD_AGP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32 31 30 29 28 27 26 25 REF 0 REF 1 /F S4 * VDD_APIC APIC0 APIC1 GND_APIC APIC2 VDD_CPU GN D_ CP U CPU 1 CPU 2 VDD_CPU GN D_ CP U CPU 3 CPU_STOP#* PCI_STOP#* RST # VDD_CORE GN D_ CO RE SDATA SCL K AG P2 AG P1 GND_AGP
R E F 1 /F S 4 V D D _ A P IC A P IC 0 :1 VD D _AG P A G P 0 :2
D IV D IV CPU_STOP# PW R_DW N#
V D D _C P U P LL 1 S to p C lo c k C o n t ro l C P U 1 :3 VD D_PC I P C I_ F
W311
F S 0 :1
÷ 6 , ÷8, ÷10, ÷12
P C I_ S T O P #
S to p C lo c k C o n tro l SM Bus L o g ic P LL 2
÷2
P C I1 :8
S D ATA SCLK
RST# VDD _48 M H z 4 8 M H z /F S 3
Note: 1. Signals marked with `*' have internal pull-up resistors.
2 4 _ 4 8 M H z /F S 2
Intel, Pentium, and Celeron are registered trademarks of Intel Corporation.
Cypress Semiconductor Corporation
·
3901 Nor th First Street
·
San Jose
·
CA 95134
·
408-943-2600 March 15, 2001
Preliminary
Pin Definitions
Pin Name RST# Pin No. 32 Pin Type Pin Description
W311
O System Reset Output: Open-drain system reset output. (opendrain) O I O CPU Clock Output: Frequency is set by the FS0:4 input or through serial input interface. The CPU1:3 outputs are gated by the CLK_STOP# input. CPU Output Control: 3.3V LVTTL-compatible input that stop CPU1:3. PCI Clock Outputs 1 through 8: Frequency is set by FS0:4 inputs or through serial input interface; see Table 5 for details. PCI1:8 outputs are gated by the PCI_STOP# input. PCI_STOP# Input: 3.3V LVTTL-compatible input that stops PCI1:8. Free-Running PCI Clock Output: Frequency is set by FS0:4 inputs or through serial input interface; see Table 5 for details. APIC Clock Output: APIC clock outputs. 48-MHz Output/Frequency Select 3: 48 MHz is provided in normal operation. In standard PC systems, this output can be used as the reference for the Universal Serial Bus host controller. This pin also serves as a power-on strap option to determine device operating frequency as described in Table 5. 24_48-MHz Output/Frequency Select 2: In standard PC systems, this output can be used as the clock input for a Super I/O chip. The output frequency is controlled by Configuration Byte 3 bit[6]. The default output frequency is 24 MHz. This pin also serves as a power-on strap option to determine device operating frequency as described in Table 5. Reference Clock Output 1/Frequency Select 4: 3.3V 14.318-MHz output clock. This pin also serves as a power-on strap option to determine device operating frequency as described in Table 5. Reference Clock Output 0: 3.3V 14.318-MHz output clock. Clock pin for SMBus circuitry. Data pin for SMBus circuitry. Crystal Connection or External Reference Frequency Input: This pin has dual functions. It can be used as an external 14.318-MHz crystal connection or as an external reference frequency input. Crystal Connection: An input connection for an external 14.318-MHz crystal. If using an external reference, this pin must be left unconnected. Power Connection: Power supply for core logic, PLL circuitry, PCI outputs, reference outputs, 48-MHz output, and 24_48-MHz output, connect to 3.3V supply.
CPU1:3 CPU_STOP# PCI1:8
39, 38, 35 34 10, 11, 13, 14, 16, 17, 18, 20 33 9 45, 44, 42 6
PCI_STOP# PCI_F APIC0:2 48MHz/FS3
O O O I/O
24_48MHz/ FS2
7
I/O
REF1/FS4
47
I/O
REF0 SCLK SDATA X1
48 28 29 3
O I I/O I
X2 VDD_REF, VDD_48MHz, VDD_PCI, VDD_AGP , VDD_CORE VDD_CPU, VDD_APIC GND_REF, GND_48MHz, GND_PCI, GND_AGP , GND_CORE, GND_CPU, GND_APIC
4 1, 5,15, 24, 31
I P
41, 46, 37 2, 8, 12, 19, 25, 30, 36, 40, 43
P G
Power Connection: Power supply for APIC and CPU output buffers, connect to 2.5V. Ground Connections: Connect all ground pins to the common system ground plane.
2
Preliminary
Serial Data Interface The W312 features a two-pin, serial data interface that can be used to configure internal register settings that control particular device functions. Data Protocol The clock driver serial protocol supports byte/word write, byte/word read, block write, and block read operations from the Table 1. Command Code Definition Bit 7 6:0 Descriptions 0 = Block read or block write operation 1 = Byte/Word read or byte/word write operation
W311
controller. For block write/read operation, the bytes must be accessed in sequential order from lowest to highest byte with the ability to stop after any complete byte has been transferred. For byte/word write and byte read operations, system controller can access individual indexed byte. The offset of the indexed byte is encoded in the command code. The definition for the command code is defined as follows:
Byte offset for byte/word read or write operation. For block read or write operations, these bits need to be set at `0000000'.
Table 2. Block Read and Block Write Protocol Block Write Protocol Bit 1 2:8 9 10 11:18 19 20:27 28 29:36 37 38:45 46 ... ... ... ... Star t Slave address - 7 bits Write Acknowledge from slave Command Code - 8 bits `00000000' stands for block operation Acknowledge from slave Byte Count - 8 bits Acknowledge from slave Data byte 0 - 8 bits Acknowledge from slave Data byte 1 - 8 bits Acknowledge from slave Data Byte N/Slave Acknowledge... Data Byte N - 8 bits Acknowledge from slave Stop Description Bit 1 2:8 9 10 11:18 19 20 21:27 28 29 30:37 38 39:46 47 48:55 56 ... ... ... ... Star t Slave address - 7 bits W r i te Acknowledge from slave Command Code - 8 bits `00000000' stands for block operation Acknowledge from slave Repeat start Slave address - 7 bits Read Acknowledge from slave Byte count from slave - 8 bits Acknowledge Data byte from slave - 8 bits Acknowledge Data byte from slave - 8 bits Acknowledge Data bytes from slave/Acknowledge Data byte N from slave - 8 bits Not Acknowledge Stop Block Read Protocol Description
3