- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄223514 > C9851BT PROC SPECIFIC CLOCK GENERATOR, PDSO48 PDF資料下載
參數(shù)資料
| 型號： | C9851BT |
| 元件分類： | 時(shí)鐘產(chǎn)生/分配 |
| 英文描述： | PROC SPECIFIC CLOCK GENERATOR, PDSO48 |
| 封裝： | TSSOP-48 |
| 文件頁數(shù)： | 3/13頁 |
| 文件大小： | 131K |
| 代理商： | C9851BT |
+/+
…when timing is critical
C9851
Clock Generator for Pentium
III Server and Workstation Applications
Preliminary
INTERNATIONAL MICROCIRCUITS, INC. 525 LOS COCHES ST.
1.0
2/1/2000
MILPITAS, CA TEL 408-263-6300, FAX 408-263-6571
Page 11 of 13
http://www.imicorp.com
Suggested Oscillator Crystal Parameters
Characteristic
Symbol
Min
Typ
Max
Units
Conditions
Frequency
Fo
14.17
14.31818
14.46
MHz
Tolerance
TC
-
+/-100
PPM
Note 1
Frequency Stability
TS
-
+/- 100
PPM
Stability (TA -10 to +60C) Note 1
Operating Mode
-
Parallel Resonant, Note 1
Load Capacitance
CXTAL
-
20
-
pF
The crystal’s rated load. Note 1
Effective Series
Resistance (ESR)
RESR
-
40
-
Ohms
Note 2
Note1:
For best performance and accurate frequencies from this device, It is recommended but not mandatory that the chosen
crystal meets or exceeds these specifications
Note 2: Larger values may cause this device to exhibit oscillator startup problems
To obtain the maximum accuracy, the total circuit loading capacitance should be equal to CXTAL. This loading capacitance is the
effective capacitance across the crystal pins and includes the clock generating device pin capacitance (CFTG), any circuit trace
capacitance (CPCB), and any onboard discrete load capacitance (CDISC).
The following formula and schematic illustrates the application of the loading specification of a crystal (CXTAL)for a design.
CL = (CXINPCB + CXINFTG + CXINDISC) X (CXOUTPCB + CXOUTFTG + CXOUTDISC)
(CXINPCB + CXINFTG + CXINDISC) + (CXOUTPCB + CXOUTFTG + COUTDISC)
Where:
CXTAL
= the load rating of the crystal
CXOUTFTG
= the clock generators XIN pin effective device internal capacitance to ground
CXOUTFTG
= the clock generators XOUT pin effective device internal capacitance to ground
CXINPCB
= the effective capacitance to ground of the crystal to device PCB trace
CXOUTPCB
= the effective capacitance to ground of the crystal to device PCB trace
CXINDISC
= any discrete capacitance that is placed between the XIN pin and ground
CXOUTDISC = any discrete capacitance that is placed between the XOUT pin and ground
C
XINPCB
C
XOUTPCB
C
XOUTDISC
C
XINDISC
C
XINFTG
C
XOUTFTG
XIN
XOUT
Clock Generator
As an example, and using this formula for this datasheet’s device, a design that has no discrete loading capacitors (CDISC) and each
of the crystal to device PCB traces has a capacitance (CPCB) to ground of 4pF (typical value) would calculate as:
CL = (4pF + 36pF + 0pF) X (4pF + 36pF + 0pF)
= 40 X 40
= 1600
= 20pF
(4pF + 36pF + 0pF) + (4pF + 36pF + 0pF)
40 + 40
80
Therefore to obtain output frequencies that are as close to this data sheets specified values as possible, in this design example, you
should specify a parallel cut crystal that is designed to work into a load of 20pF
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| CA-1869-02 | 2 CONTACT(S), MALE, STRAIGHT TWO PART BOARD CONNECTOR, SOLDER |
| CA-1869-03 | 3 CONTACT(S), MALE, STRAIGHT TWO PART BOARD CONNECTOR, SOLDER |
| CA-1869-04 | 4 CONTACT(S), MALE, STRAIGHT TWO PART BOARD CONNECTOR, SOLDER |
| CA-1869-05 | 5 CONTACT(S), MALE, STRAIGHT TWO PART BOARD CONNECTOR, SOLDER |
| CA-1869-06 | 6 CONTACT(S), MALE, STRAIGHT TWO PART BOARD CONNECTOR, SOLDER |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| C9851BY | 制造商:CYPRESS 制造商全稱:Cypress Semiconductor 功能描述:Clock Generator for Pentium III Server and Workstation Applications |
| C98520-000 | 制造商:TE Connectivity 功能描述:VARISTOR 240V 14MM RADIAL T/R 制造商:TE Connectivity 功能描述:VARISTOR 240V 6KA DISC 14MM |
| C9870G | 制造商:CYPRESS 制造商全稱:Cypress Semiconductor 功能描述:High Performance Pentium? 4 Clock Synthesizer |
| C9870GT | 制造商:CYPRESS 制造商全稱:Cypress Semiconductor 功能描述:High Performance Pentium㈢ 4 Clock Synthesizer |
| C9870GY | 制造商:CYPRESS 制造商全稱:Cypress Semiconductor 功能描述:High Performance Pentium? 4 Clock Synthesizer |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。