APPLICATION NOTE AN1659 TW2880P-BC2-GR Chip Application Note Rev. 2.00 January 26, 2012 Table of Contents Section 1: Clockgen and PLL ................................................................................................................................................. 11 Introduction .............................................................................................................................................................................. 11 SCLK ........................................................................................................................................................................................... 11 Clock Listing ................................................................................................................................................................... 12 Register Setting for SPLL ............................................................................................................................................... 12 MCLK .......................................................................................................................................................................................... 13 Introduction ................................................................................................................................................................... 13 Master Clock Calculation ............................................................................................................................................... 14 Clock Relationship .......................................................................................................................................................... 15 VCLK ........................................................................................................................................................................................... 16 Popular Main Display Clocks ......................................................................................................................................... 17 Dual Monitor Setting ....................................................................................................................................................... 18 Using SCLK Clock Group For Dual Monitor Clock ....................................................................................................... 19 Example ................................................................................................................................................................... 19 MCLK registers ...................................................................................................................................................... 20 VCLK registers ....................................................................................................................................................... 20 VCLK registers ....................................................................................................................................................... 20 Techwell Terminal Tool Setting.............................................................................................................................................. 21 Layout of the CFG File ..................................................................................................................................................... 21 Explanation ................................................................................................................................................................... 21 Section 2: PCB Layout Guide ................................................................................................................................................. 23 Introduction .............................................................................................................................................................................. 23 Placement Suggestions.................................................................................................................................................. 23 Signal Integrity ................................................................................................................................................................. 23 Power Regulator and Noise Filtering ............................................................................................................................ 23 Power Distribution ........................................................................................................................................................... 24 TW2880 Power Rails ...................................................................................................................................................... 24 SDRAM ...................................................................................................................................................................................... 27 Introduction ................................................................................................................................................................... 27 Termination Resistors..................................................................................................................................................... 27 Equi-Length Line Rule ..................................................................................................................................................... 27 DAC ............................................................................................................................................................................................ 28 Introduction ................................................................................................................................................................... 28 Power Supply ................................................................................................................................................................... 28 Proper Termination ......................................................................................................................................................... 28 Connection Example ....................................................................................................................................................... 28 PCB Layout Considerations ............................................................................................................................................ 29 Recommended Routing/Layout Rules .............................................................................................................. 29 AN1659 Rev. 2.00 Page 1 of 223 January 26, 2012 TW2880P-BC2-GR Chip Application Note HDMI .......................................................................................................................................................................................... 30 General Description ........................................................................................................................................................ 30 Signal Integrity ................................................................................................................................................................. 30 Impedance Control ............................................................................................................................................... 30 45°Bends ............................................................................................................................................................ 32 Skew Control .......................................................................................................................................................... 33 Symmetrical Design ............................................................................................................................................. 34 Power and Ground ........................................................................................................................................................... 35 Power and GND Planes ........................................................................................................................................ 35 Plane Isolation ....................................................................................................................................................... 36 Recommendation of Layer Structure ................................................................................................................ 37 Recommendation of power supply pin connections ....................................................................................... 38 Clocking Design ............................................................................................................................................................... 39 Requirement of Jitter ........................................................................................................................................... 39 Additional Parts (for ESD and EMI) ............................................................................................................................... 40 ESD Protector .......................................................................................................................................................