A2811A-08SR中文资料

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October 2003 rev
Low-Power EMI Reduction IC
Features
FCC approved method of EMI attenuation Provides up to 15 dB EMI reduction Generates 1X, 2X, and 4X low EMI spread spectrum clock of the input frequency 1X: P2811, 2X: P2812, 4X: P2814 Optimized for input frequency range from 10 to 40 MHz P2811: 10 to 40 MHz P2812: 10 to 40 MHz P2814: 10 to 40 MHz Internal loop filter minimizes external components and board space Selectable spread options: Down Spread and Center Spread Low inherent cycle-to-cycle jitter Eight spread % selections: ±0.625% to –3.5% 3.3 V operating voltage CMOS/TTL compatible inputs and outputs Pinout compatible with Cypress CY25811, CY25812, and CY25814 Products available for industrial temperature range Available in 8-pin SOIC and TSSOP Deviation and Spread Option Selections section). These combinations include Down Spread, Center Spread and percentage deviation range from ±0.625% to -3.50%. The P28xx reduces electromagnetic interference (EMI) at the clock source, allowing a system wide EMI reduction for all the down stream clocks and data dependent signals. The P28xx allows significant system cost savings by reducing the number of circuit board layers, ferrite beads, shielding, and other passive components that are traditionally required to pass EMI regulations. The P28xx modulates the output of a single PLL in order to “spread” the bandwidth of a synthesized clock, thereby decreasing 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 clock generators. generation”. The P28xx uses the most efficient and optimized modulation profile approved by the FCC and is implemented by using a proprietary all-digital method. Lowering EMI by increasing a signal’s bandwidth is called “spread spectrum clock
P2811/12/14
Product Description
The P28xx is a versatile spread spectrum frequency modulator designed specifically for input clock frequencies from 10 to 40 MHz (see Input/Output Frequency Range Selections). The P28xx can generate an EMI reduced clock from crystal, ceramic resonator, or system clock. The P28xx-A and P28xx-B offer various combinations of spread options and percentage deviations (see Output Frequency
Applications
The P28xx is targeted towards EMI management for memory interfaces in mobile graphic chipsets and highspeed digital applications such as PC peripheral devices, consumer electronics, and embedded controller systems.
Block Diagram
Alliance Semiconductor 2575, Augustine Drive ? Santa Clara, CA ? Tel: 408.855.4900 ? Fax: 408.855.4999 ? https://www.wendangku.net/doc/4717471970.html,
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元器件交易网https://www.wendangku.net/doc/4717471970.html,
October 2003 rev
Pin Configuration
P2811/12/14
Pin Description Pin# 1 2 3 SRS 4 5 6 7 8 VDD XOUT P I ModOut FRS O I I Pin Name XIN VSS D_C Type I P I Description Connect to externally generated clock signal or crystal. Ground Connection. Connect to system ground. Digital logic input used to select Down (LOW) or Center (HIGH) Spread Options (see Output Frequency Deviation and Spread Option Selections). This pin has an internal pull-up resistor. Spread Range Selection. Digital logic input used to select frequency deviation (see Output Frequency Deviation and Spread Option Selections). This pin has an internal pull-up resistor. Spread Spectrum clock output (see Input/Output Frequency Range Selections and Output Frequency Deviation and Spread Option Selections). Frequency Range Selection. Digital logic input used to select input frequency range (see Input/Output Frequency Range Selections). This pin has an internal pull-up resistor. Connect to +3.3 V Connect to crystal. No connect if externally generated clock signal is used.
Input/Output Frequency Range Selections Pin 6 FRS 0 1 Part number P2812 (2X) Input Output (MHz) (MHz) 10-20 20-40 20-40 40-80 Modulation rate Input frequency / 448 Input frequency / 896
P2811 (1X) Input Output (MHz) (MHz) 10-20 20-40 10-20 20-40
P2814 (4X) Input Output (MHz) (MHz) 10-20 20-40 40-80 80-160
Low Power EMI Reduction IC
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Output Frequency Deviation and Spread Option Selections Part number Pin 3 D_C 0 P2811/12/14A 0 1 1 0 P2811/12/14B 0 1 1 Absolute Maximum Ratings Symbol VDD, VIN TSTG TA Parameter Voltage on any pin with respect to GND Storage temperature Operating temperature Rating -0.5 to + 7.0 -65 to +125 0 to 70 Unit V °C °C Pin 4 SRS 0 1 0 1 0 1 0 1 Output frequency deviation and spread option -2.50% (Down) -3.50% (Down) +/-1.25% (Center) +/-1.75% (Center) -1.25% (Down) -1.75% (Down) +/-0.625% (Center) +/-0.875% (Center)
P2811/12/14
DC Electrical Characteristics 3.3 V, 25° C Symbol VIL VIH IIL IIH IXOL IXOH VOL VOH IDD ICC VDD tON ZOUT Parameter Input Low Voltage Input High Voltage Input low Current (inputs D_C, SRS, and FRS) Input High Current XOUT Output Low Current (@ 0.4V, VDD = 3.3V) XOUT Output High Current (@ 2.5V, VDD = 3.3V) Output Low Voltage (VDD=3.3V, IOL = 20 mA) Output High Voltage (VDD=3.3V, IOH = 20 mA) Static Supply Current Standby Mode Dynamic Supply Current Normal Mode (3.3V and 25 pF probe loading) Operating Voltage Power Up Time (First locked clock cycle after power up) Clock Output Impedance Min GND – 0.3 – -60.00 – 2.00 – – – – 7.1 fIN-min – – – Typ – – – – – – – – 4.5 – 3.3 0.18 50 Max 0.8 VDD + 0.3 -20.00 1.00 12.00 12.00 0.4 2.8 – 13.9 fIN-max – – – Unit V V μA μA mA mA V V mA mA V mS ?
Low Power EMI Reduction IC
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AC Electrical Characteristics 3.3 V, 25° C Symbol fIN fOUT Parameter Input frequency P2811/12/14 Output frequency P2811 Output frequency P2812 tLH 1 tHL 1 tJC tD Output frequency P2814 Output rise time (measured at 0.8V to 2.0V) Output fall time (measured at 2.0V to 0.8V) Jitter (cycle to cycle) Output duty cycle Min 10 10 20 40 Typ – – – – 0.69 0.66 -200 45 – 50 200 55 Max 40 40 80 160 Unit MHz MHz MHz MHz ns ns ps %
P2811/12/14
1. tLH and tHL are measured into a capacitive load of 15 pF
Low Power EMI Reduction IC
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Package Information
P2811/12/14
Mechanical Package Outline 8-Pin SOIC
Symbol A A1 A2 B C D E e H L a
Dimensions in inches Min 0.057 0.004 0.053 0.012 0.004 0.186 0.148 Nor 0.064 0.007 0.061 0.016 0.006 0.194 0.156 0.050 BSC 0.224 0.012 0° 0.236 0.020 5° 0.248 0.028 8° Max 0.071 0.010 0.069 0.020 0.01 0.202 0.164
Dimensions in millimeters Min 1.45 0.10 1.35 0.31 0.10 4.72 3.75 Nor 1.63 0.18 1.55 0.41 0.15 4.92 3.95 1.27 BSC 5.70 0.30 0° 6.00 0.50 5° 6.30 0.70 8° Max 1.80 0.25 1.75 0.51 0.25 5.12 4.15
Note: Controlling dimensions are millimeters SOIC – 0.074 grams unit weight
Low Power EMI Reduction IC
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Mechanical Package Outline 8-Pin TSSOP
P2811/12/14
Dimensions in inches Symbol A A1 A2 B C D E e H L a 0.244 0.018 0° 0.002 0.031 0.007 0.004 0.114 0.169 0.118 0.173 0.026 BSC 0.252 0.024 0.260 0.030 8° 0.039 Min Nor Max 0.047 0.006 0.041 0.012 0.008 0.122 0.177
Dimensions in millimeters Min Nor Max 1.10 0.05 0.80 0.19 0.09 2.90 4.30 3.00 4.40 0.65 BSC 6.20 0.45 0° 6.40 0.60 6.60 0.75 8° 1.00 0.15 1.05 0.30 0.20 3.10 4.50
5°
5°
Note: Controlling dimensions are millimeters TSSOP – 0.034 grams unit weight
Low Power EMI Reduction IC
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Ordering Codes Part Number P2811A-08ST P2812A-08ST P2814A-08ST P2811A-08SR P2812A-08SR P2814A-08SR P2811A-08TT P2812A-08TT P2814A-08TT P2811A-08TR P2812A-08TR P2814A-08TR Device Ordering Information Marking P2811A P2812A P2814A P2811A P2812A P2814A P2811A P2812A P2814A P2811A P2812A P2814A Package Type 8-pin SOIC, tube 8-pin SOIC, tube 8-pin SOIC, tube 8-pin SOIC, tape reel 8-pin SOIC, tape reel 8-pin SOIC, tape reel 8-pin TSSOP, tube 8-pin TSSOP, tube 8-pin TSSOP, tube 8-pin TSSOP, tape reel 8-pin TSSOP, tape reel 8-pin TSSOP, tape reel 2,500 2,500 2,500 2,500 2,500 2,500 Qty per reel Temperature 0 to 70 0 to 70 0 to 70 0 to 70 0 to 70 0 to 70 0 to 70 0 to 70 0 to 70 0 to 70 0 to 70 0 to 70
P2811/12/14
X
2 8 X X
X -
0 8 X X
Package: ST – SOIC, TUBE SR - SOIC, T/R TT – TSSOP, TUBE TR - TSSOP, T/R
Pin Count
F = Pb FREE
DEVICE NUMBER
Flow: P = Commercial Temperature Range (0°C to 70°C) I = Industrial Temperature Range (-25°C to 85°C) A = Automotive Temperature Range (-40°C to 125°C)
Licensed under US patent Nos 5,488,627 and 5,631,920. Preliminary datasheet. Specification subject to change without notice.
Low Power EMI Reduction IC
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P2811/12/14
Alliance Semiconductor Corporation 2595, Augustine Drive, Santa Clara, CA 95054 Tel# 408-855-4900 Fax: 408-855-4999 https://www.wendangku.net/doc/4717471970.html,
Copyright ? Alliance Semiconductor All Rights Reserved Preliminary Information Part Number: P2811/12/14 Document Version:
? Copyright 2003 Alliance Semiconductor Corporation. All rights reserved. Our three-point logo, our name and Intelliwatt are trademarks or registered trademarks of Alliance. All other brand and product names may be the trademarks of their respective companies. Alliance reserves the right to make changes to this document and its products at any time without notice. Alliance assumes no responsibility for any errors that may appear in this document. The data contained herein represents Alliance's best data and/or estimates at the time of issuance. Alliance reserves the right to change or correct this data at any time, without notice. If the product described herein is under development, significant changes to these specifications are possible. The information in this product data sheet is intended to be general descriptive information for potential customers and users, and is not intended to operate as, or provide, any guarantee or warrantee to any user or customer. Alliance does not assume any responsibility or liability arising out of the application or use of any product described herein, and disclaims any express or implied warranties related to the sale and/or use of Alliance products including liability or warranties related to fitness for a particular purpose, merchantability, or infringement of any intellectual property rights, except as express agreed to in Alliance's Terms and Conditions of Sale (which are available from Alliance). All sales of Alliance products are made exclusively according to Alliance's Terms and Conditions of Sale. The purchase of products from Alliance does not convey a license under any patent rights, copyrights; mask works rights, trademarks, or any other intellectual property rights of Alliance or third parties. Alliance does not authorize its products for use as critical components in life-supporting systems where a malfunction or failure may reasonably be expected to result in significant injury to the user, and the inclusion of Alliance products in such life-supporting systems implies that the manufacturer assumes all risk of such use and agrees to indemnify Alliance against all claims arising from such use.
Low Power EMI Reduction IC
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