参数资料
型号: I2784A-08SR
元件分类: 时钟产生/分配
英文描述: 312 MHz, OTHER CLOCK GENERATOR, PDSO8
封装: SOIC-8
文件页数: 1/11页
文件大小: 169K
代理商: I2784A-08SR
July 2005
P2781/82/84
rev 1.5
Alliance Semiconductor
2575, Augustine Drive
Santa Clara, CA Tel: 408.855.4900 Fax: 408.855.4999 www.alsc.com
Notice: The information in this document is subject to change without notice.
General Purpose EMI Reduction IC
Features
Provides up to 15dB of EMI suppression
FCC approved method of EMI attenuation
Generates a 1X, 2X, and 4X low EMI spread
spectrum clock of the input frequency
Input frequency range from 3 to 78MHz
External loop filter for spread % adjustment
Spreading ranges from ±0.25% to ±5.0%
Ultra low cycle-to-cycle jitter
Zero-cycle slip
3.3V operating voltage range
10 mA output drives
TTL or CMOS compatible outputs
Ultra-low power CMOS design
P278XA is available in 8 pin SOIC and TSSOP
Packages
Available for industrial and automotive
temperature ranges.
Product Description
The P278xA is a versatile spread spectrum frequency
modulator designed specifically for digital camera and
other digital video and imaging applications. The P278xA
reduces electromagnetic interference (EMI) at the clock
source, which provides system wide reduction of EMI of
all clock dependent signals. The P278xA allows
significant system cost savings by reducing the number of
circuit board layers and shielding that are traditionally
required to pass EMI regulations.
The P278xA uses the most efficient and optimized
modulation profile approved by the FCC. The P278xA
modulates the output of a single PLL in order to “spread”
the bandwidth of a synthesized clock and, more
importantly, decreases the peak amplitudes of its
harmonics. This results in significantly lower system EMI
compared to the typical narrow band signal produced by
oscillators and most frequency generators. Lowering EMI
by increasing a signal’s bandwidth is called spread
spectrum clock generation.
Applications
The P278xA is targeted towards MFP, xDSL, fax modem,
set-top box, USB controller, DSC, and embedded systems.
Block Diagram
Crystal
Oscillator
Frequency
Divider
Feedback
Divider
Phase
Detector
Modulation
Output
Divider
VCO
XIN /CLKIN
XOUT
FS0
FS1
LF
VDD
VSS
PLL
ModOUT
相关PDF资料
PDF描述
I2781A-08TT 78 MHz, OTHER CLOCK GENERATOR, PDSO8
I2781A-08TR 78 MHz, OTHER CLOCK GENERATOR, PDSO8
I2782A-08SR 156 MHz, OTHER CLOCK GENERATOR, PDSO8
I2782A-08ST 156 MHz, OTHER CLOCK GENERATOR, PDSO8
I2782A-08TR 156 MHz, OTHER CLOCK GENERATOR, PDSO8
相关代理商/技术参数
参数描述
I2784A-08ST 制造商:ALSC 制造商全称:Alliance Semiconductor Corporation 功能描述:General Purpose EMI Reduction IC
I2784A-08TR 制造商:ALSC 制造商全称:Alliance Semiconductor Corporation 功能描述:General Purpose EMI Reduction IC
I2784A-08TT 制造商:ALSC 制造商全称:Alliance Semiconductor Corporation 功能描述:General Purpose EMI Reduction IC
I2784AF-08SR 制造商:ALSC 制造商全称:Alliance Semiconductor Corporation 功能描述:General Purpose EMI Reduction IC
I2784AF-08ST 制造商:ALSC 制造商全称:Alliance Semiconductor Corporation 功能描述:General Purpose EMI Reduction IC