Document
P1817A, P1817B
Product Preview Low-Power Mobile VGA EMI Reduction IC
Description
The P1817 is a versatile spread spectrum frequency modulator designed specifically for input clock frequencies. The P1817 reduces electromagnetic interference (EMI) at the clock source, allowing system wide reduction of EMI of down stream clock and data dependent signals. The P1817 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 P1817 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.’
The P1817 uses the most efficient and optimized modulation profile approved by the FCC and is implemented in a proprietary all digital method.
http://onsemi.com
SOIC−8 S SUFFIX CASE 751BD
TSSOP−8 T SUFFIX CASE 948AL
PIN CONFIGURATION
1 CLKIN / XIN
XOUT
VSS
VDD
SR0 REF
SSON / SBM
ModOUT
Applications The P1817 is targeted towards notebook LCD displays, and other
displays using an LVDS interface, PC peripheral devices, and embedded systems.
Features
• FCC Approved Method of EMI Attenuation • Generates a Low EMI Spread Spectrum Clock of the Input Frequency
(Top View)
ORDERING INFORMATION
See detailed ordering and shipping information in the package dimensions section on page 7 of this data sheet.
• Optimized for Frequency Range from:
• P1817A – 20 to 32 MHz • P1817B – 10 to 20 MHz
• Internal Loop Filter Minimizes External Components and Board Space
• Two Selectable Spread Ranges • Low Inherent Cycle−to−Cycle Jitter
• 3.3 V or 5 V Operating Voltage Range
• TTL or CMOS Compatible Inputs and Outputs
• Ultra−low Power CMOS Design
• 3.17 mA @ 3.3 V, 10 MHz | 6.20 mA @ 5.0 V, 10 MHz • 4.28 mA @ 3.3 V, 14 MHz | 7.50 mA @ 5.0 V, 14 MHz • 5.50 mA @ 3.3 V, 20 MHz | 9.50 mA @ 5.0 V, 20 MHz
• Supports Notebook VGA and Other LCD Timing Controller Applications
• SSON / SBM Pin for Spread Spectrum On/Off and Standby Mode Controls
• Available in 8−pin SOIC and TSSOP • These are Pb−Free Devices
This document contains information on a product under development. ON Semiconductor reserves the right to change or discontinue this product without notice.
© Semiconductor Components Industries, LLC, 2011
August, 2011 − Rev. P3
1
Publication Order Number: P1817A/D
CLKIN / XIN XOUT
REF
P1817A, P1817B
SR0 SSON
VDD
Frequency Divider
Feedback Divider
Modulation
Phase Detector
Loop Filter
PLL
VCO
Output Divider
ModOUT
VSS Figure 1. Block Diagram
Table 1. ABSOLUTE MAXIMUM RATINGS
Symbol
Parameter
Rating
Unit
VDD, VIN Voltage on any pin with respect to GND
−0.5 to +7.0
V
TSTG
Stor.