- 您现在的位置：买卖IC网 > PDF目录377124 > ICS83908I-02 (Integrated Device Technology, Inc.) LOW SKEW, 1-TO-8 CRYSTAL-TO-LVCMOS FANOUT BUFFER PDF资料下载
参数资料
| 型号： | ICS83908I-02 |
| 厂商： | Integrated Device Technology, Inc. |
| 英文描述： | LOW SKEW, 1-TO-8 CRYSTAL-TO-LVCMOS FANOUT BUFFER |
| 中文描述： | 低偏移，1至8晶体到的LVCMOS扇出缓冲器 |
| 文件页数： | 11/16页 |
| 文件大小： | 301K |
| 代理商： | ICS83908I-02 |
IDT
/ ICS
LVCMOS FANOUT BUFFER
11
ICS83908AGI-02 REV. B JULY 24, 2007
ICS83908I-02
LOW SKEW, 1-TO-8 CRYSTAL-TO-LVCMOS FANOUT BUFFER
PRELIMINARY
A
PPLICATION
I
NFORMATION
F
IGURE
1. Crystal Input Interface
C
RYSTAL
I
NPUT
I
NTERFACE
A crystal can be characterized for either series or parallel mode
operation. The ICS83908I-02 has a built-in crystal oscillator
circuit. This interface can accept either a series or parallel
crystal without additional components and generate fre-
quencies with accuracy suitable for most applications. Additional
accuracy can be achieved by adding two small capacitors C1
and C2 as shown in
Figure 1
. Typical results using parallel 18pF
crystals are shown in Table 5.
C1
15p
X1
18pF Parallel Crystal
C2
15p
XTAL_OUT
XTAL_IN
LVCMOS
TO
XTAL I
NTERFACE
The XTAL_IN input can accept a single-ended LVCMOS signal
through an AC coupling capacitor. A general interface diagram is
shown in
Figure 2.
The XTAL_OUT pin can be left floating. The
input edge rate can be as slow as 10ns. For LVCMOS inputs, it is
recommended that the amplitude be reduced from full swing to
half swing in order to prevent signal interference with the power
rail and to reduce noise. This configuration requires that the output
F
IGURE
2. G
ENERAL
D
IAGRAM
FOR
LVCMOS D
RIVER
TO
XTAL I
NPUT
I
NTERFACE
impedance of the driver (Ro) plus the series resistance (Rs) equals
the transmission line impedance. In addition, matched termination
at the crystal input will attenuate the signal in half. This can be
done in one of two ways. First, R1 and R2 in parallel should equal
the transmission line impedance. For most 50
Ω
applications, R1
and R2 can be 100
Ω
. This can also be accomplished by removing
R1 and making R2 50
Ω
.
R2
Zo = 50
VDD
Ro
Zo = Ro + Rs
R1
VDD
XTAL_IN
XTAL_OUT
.1uf
Rs
相关PDF资料 |
PDF描述 |
|---|---|
| ICS843031-01 | FEMTOCLOCKS⑩ CRYSTAL-TO- 3.3V, 2.5V LVPECL CLOCK GENERATOR |
| ICS843031AG-01 | FEMTOCLOCKS⑩ CRYSTAL-TO- 3.3V, 2.5V LVPECL CLOCK GENERATOR |
| ICS843031AG-01LF | FEMTOCLOCKS⑩ CRYSTAL-TO- 3.3V, 2.5V LVPECL CLOCK GENERATOR |
| ICS843031AG-01LFT | FEMTOCLOCKS⑩ CRYSTAL-TO- 3.3V, 2.5V LVPECL CLOCK GENERATOR |
| ICS843031AG-01T | FEMTOCLOCKS⑩ CRYSTAL-TO- 3.3V, 2.5V LVPECL CLOCK GENERATOR |
相关代理商/技术参数 |
参数描述 |
|---|---|
| ICS83940 | 制造商:ICS 制造商全称:ICS 功能描述:LOW SKEW, 1-TO-18 LVCMOS FANOUT BUFFER |
| ICS83940-01 | 制造商:ICS 制造商全称:ICS 功能描述:LOW SKEW, 1-TO-18 LVCMOS FANOUT BUFFER |
| ICS83940-02 | 制造商:ICS 制造商全称:ICS 功能描述:LOW SKEW, 1-TO-18 LVCMOS FANOUT BUFFER |
| ICS83940AY | 制造商:ICS 制造商全称:ICS 功能描述:LOW SKEW, 1-TO-18 LVCMOS FANOUT BUFFER |
| ICS83940AY-01 | 制造商:ICS 制造商全称:ICS 功能描述:LOW SKEW, 1-TO-18 LVCMOS FANOUT BUFFER |
发布紧急采购，3分钟左右您将得到回复。