W134M/W134S Direct Rambus™ Clock Generator Features Overview • Differential clock source for Direct Rambus™ memory subsystem for up to 800-MHz data transfer rate • Provide synchronization flexibility: the Rambus® Channel can optionally be synchronous to an external system or processor clock • Power managed output allows Rambus Channel clock to be turned off to minimize power consumption for mobile applications • Works with Cypress CY2210, W133, W158, W159, W161, and W167 to support Intel® architecture platforms • Low-power CMOS design packaged in a 24-pin, 150-mil SSOP package The Cypress W134M/W134S provides the differential clock signals for a Direct Rambus memory subsystem. It includes signals to synchronize the Direct Rambus Channel clock to an external system clock but can also be used in systems that do not require synchronization of the Rambus clock. Key Specifications Supply Voltage:...................................... VDD = 3.3V±0.165V Operating Temperature: ................................... 0°C to +70°C Input Threshold: .................................................. 1.5V typical Maximum Input Voltage: .........................................VDD+0.5V Maximum Input Frequency: ..................................... 100 MHz Output Duty Cycle: .................................. 40/60% worst case Output Type: ............................Rambus signaling level (RSL) Block Diagram REFCLK MULT0:1 PCLKM Pin Configuration PLL Phase Alignment Output Logic CLK VDDIR 1 24 S0 REFCLK 2 23 S1 VDD 3 22 VDD GND 4 21 GND GND 5 20 CLK PCLKM 6 19 NC SYNCLKN 7 18 CLKB GND 8 17 GND CLKB VDD 9 16 VDD VDDIPD 10 15 MULT0 STOPB 11 14 MULT1 PWRDNB 12 13 GND SYNCLKN S0:1 Test Logic STOPB Direct Rambus is a trademark and Rambus is a registered trademark of Rambus Inc. Intel is a registered trademark of Intel Corporation. Cypress Semiconductor Corporation • Powered by ICminer.com Electronic-Library Service CopyRight 2003 3901 North First Street • San Jose • CA 95134 • 408-943-2600 February 18, 2000, rev. *A W134M/W134S Pin Definitions Pin No. 2 Pin Type I PCLKM 6 I SYNCLKN 7 I STOPB 11 I PWRDNB 12 I MULT 0:1 15, 14 I Pin Name REFCLK Pin Description Reference Clock Input: Reference clock input, normally supplied by a system frequency synthesizer (Cypress W133). Phase Detector Input: The phase difference between this signal and SYNCLKN is used to synchronize the Rambus Channel Clock with the system clock. Both PCLKM and SYNCLKN are provided by the Gear Ratio Logic in the memory controller. If Gear Ratio Logic is not used, this pin would be connected to Ground. Phase Detector Input: The phase difference between this signal and PCLKM is used to synchronize the Rambus Channel Clock with the system clock. Both PCLKM and SYNCLKN are provided by the Gear Ratio Logic in the memory controller. If Gear Ratio Logic is not used, this pin would be connected to Ground. Clock Output Enable: When this input is driven to active LOW, it disables the differential Rambus Channel clocks. Active LOW Power-Down: When this input is driven to active LOW, it disables the differential Rambus Channel clocks and places the W134M/W134S in power-down mode. PLL Multiplier Select: These inputs select the PLL prescaler and feedback dividers to determine the multiply ratio for the PLL for the input REFCLK. MULT0 0 0 1 1 CLK, CLKB S0, S1 20, 18 24, 23 O I 19 1 10 RefV RefV VDD 3, 9, 16, 22 P GND 4, 5, 8, 13, 17, 21 G W134S PLL/REFCLK 4 6 8 5.333 Complementary Output Clock: Differential Rambus Channel clock outputs. Mode Control Input: These inputs control the operating mode of the W134M/W134S. S0 0 0 1 1 NC VDDIR VDDIPD W134M PLL/REFCLK 4.5 6 8 5.333 MULT1 0 1 1 0 S1 0 1 0 1 MODE Normal Output Enable Test Bypass Test No Connect Reference for REFCLK: Voltage reference for input reference clock. Reference for Phase Detector: Voltage reference for phase detector inputs and StopB. Power Connection: Power supply for core logic and output buffers. Connected to 3.3V supply. Ground Connection: Connect all ground pins to the common system ground plane. Powered by ICminer.com Electronic-Library Service CopyRight 2003 2 W134M/W134S W134M/W134S Refclk Phase Align PLL Busclk D RAC Pclk/M RMC Synclk/N W133 W158 W159 W161 W167 CY2210 M N Pclk 4 DLL Synclk Gear Ratio Logic Figure 1. DDLL System Architecture face of the RAC. The DDLL together with the Gear Ratio Logic enables users to exchange data directly from the Pclk domain to the Synclk domain without incurring additional latency for synchronization. In general, Pclk and Synclk can be of different frequencies, so the Gear Ratio Logic must select the appropriate M and N dividers such that the frequencies of Pclk/M and Synclk/N are equal. In one interesting example, Pclk=133 MHz, Synclk=100 MHz, and M=4 while N=3, giving Pclk/M=Synclk/N=33 MHz. This example of the clock waveforms with the Gear Ratio Logic is shown in Figure 2. DDLL System Architecture and Gear Ratio Logic Figure 1 shows the Distributed Delay Lock Loop (DDLL) system architecture, including the main system clock source, the Direct Rambus clock generator (DRCG), and the core logic that contains the Rambus Access Cell (RAC), the Rambus Memory Controller (RMC), and the Gear Ratio Logic. (This diagram abstractly represents the differential clocks as a single Busclk wire.) The purpose of the DDLL is to frequency-lock and phase-align the core logic and Rambus clocks (Pclk and Synclk) at the RMC/RAC boundary in order to allow data transfers without incurring additional latency. In the DDLL architecture, a PLL is used to generate the desired Busclk frequency, while a distributed loop forms a DLL to align the phase of Pclk and Synclk at the RMC/RAC boundary. The output clocks from the Gear Ratio Logic, Pclk/M, and Synclk/N, are output from the core logic and routed to the DRCG Phase Detector inputs. The routing of Pclk/M and Synclk/N must be matched in the core logic as well as on the board. The main clock source drives the system clock (Pclk) to the core logic, and also drives the reference clock (Refclk) to the DRCG. For typical Intel architecture platforms, Refclk will be half the CPU front side bus frequency. A PLL inside the DRCG multiplies Refclk to generate the desired frequency for Busclk, and Busclk is driven through a terminated transmission line (Rambus Channel). At the mid-point of the channel, the RAC senses Busclk using its own DLL for clock alignment, followed by a fixed divide-by-4 that generates Synclk. After comparing the phase of Pclk/M vs. Synclk/N, the DRCG Phase Detector drives a phase aligner that adjusts the phase of the DRCG output clock, Busclk. Since everything else in the distributed loop is fixed delay, adjusting Busclk adjusts the phase of Synclk and thus the phase of Synclk/N. In this manner the distributed loop adjusts the phase of Synclk/N to match that of Pclk/M, nulling the phase error at the input of the DRCG Phase Detector. When the clocks are aligned, data can be exchanged directly from the Pclk domain to the Synclk domain. Pclk is the clock used in the memory controller (RMC) in the core logic, and Synclk is the clock used at the core logic inter- Table 1 shows the combinations of Pclk and Busclk frequencies of greatest interest, organized by Gear Ratio. Pclk Synclk Pclk/M = Synclk/N Figure 2. Gear Ratio Timing Diagram Powered by ICminer.com Electronic-Library Service CopyRight 2003 3 W134M/W134S Table 1. Supported Pclk and Busclk Frequencies, by Gear Ratio Gear Ratio and Busclk Pclk 2.0 1.5 1.33 1.0 67 MHz 267 MHz 100 MHz 133 MHz 300 MHz 267 MHz 356 MHz 150 MHz 200 MHz 400 MHz 400 MHz 400 MHz 400 MHz S0/S1 StopB W134M/W134S Refclk Phase Align PLL Busclk D RAC Pclk/M RMC Synclk/N W133 W158 W159 W161 W167 CY2210 M N 4 Pclk DLL Synclk Gear Ratio Logic Figure 3. DDLL Including Details of DRCG Figure 3 shows more details of the DDLL system architecture, including the DRCG output enable and bypass modes. directly, by bypassing the Phase Aligner. If PclkM and SynclkN are not used, those inputs must be grounded. Phase Detector Signals Selection Logic The DRCG Phase Detector receives two inputs from the core logic, PclkM (Pclk/M) and SynclkN (Synclk/N). The M and N dividers in the core logic are chosen so that the frequencies of PclkM and SynclkN are identical. The Phase Detector detects the phase difference between the two input clocks, and drives the DRCG Phase Aligner to null the input phase error through the distributed loop. When the loop is locked, the input phase error between PclkM and SynclkN is within the specification tERR,PD given in Table 14 after the lock time given in the State Transition Section. Table 2 shows the logic for selecting the PLL prescaler and feedback dividers to determine the multiply ratio for the PLL from the input Refclk. Divider A sets the feedback and divider B sets the prescaler, so the PLL output clock frequency is set by: PLLclk=Refclk*A/B. Table 2. PLL Divider Selection W134M The Phase Detector aligns the rising edge of PclkM to the rising edge of SynclkN. The duty cycle of the phase detector input clocks will be within the specification DCIN,PD given in Table 13. Because the duty cycles of the two phase detector input clocks will not necessarily be identical, the falling edges of PclkM and SynclkN may not be aligned when the rising edges are aligned. Mult0 Mult1 A B A B 0 0 9 2 4 1 0 1 6 1 6 1 1 1 8 1 8 1 1 0 16 3 16 3 Table 3 shows the logic for enabling the clock outputs, using the StopB input signal. When StopB is HIGH, the DRCG is in its normal mode, and Clk and ClkB are complementary outputs following the Phase Aligner output (PAclk). When StopB is LOW, the DRCG is in the Clk Stop mode, the output clock drivers are disabled (set to Hi-Z), and the Clk and ClkB settle to the DC voltage VX,STOP as given in Table 14. The level of VX,STOP is set by an external resistor network. The voltage levels of the PclkM and SynclkN signals are determined by the controller. The pin VDDIPD is used as the voltage reference for the phase detector inputs and should be connected to the output voltage supply of the controller. In some applications, the DRCG PLL output clock will be used Powered by ICminer.com Electronic-Library Service CopyRight 2003 W134S 4 W134M/W134S Table 3. Clock Stop Mode Selection Table 5. Power-down Mode Selection Mode StopB Clk ClkB Mode PwrDnB Clk ClkB Normal 1 PAclk PAclkB Normal 1 PAclk PAclkB Clk Stop 0 VX,STOP VX,STOP Power-down 0 GND GND Table 4 shows the logic for selecting the Bypass and Test modes. The select bits, S0 and S1, control the selection of these modes. The Bypass mode brings out the full-speed PLL output clock, bypassing the Phase Aligner. The Test mode brings the Refclk input all the way to the output, bypassing both the PLL and the Phase Aligner. In the Output Test mode (OE), both the Clk and ClkB outputs are put into a high-impedance state (Hi-Z). This can be used for component testing and for board-level testing. Table of Frequencies and Gear Ratios Table 4. Bypass and Test Mode Selection State Transitions S0 S1 Bypclk (int.) Clk ClkB Normal 0 0 Gnd PAclk PAclkB Output Test (OE) 0 1 - Hi-Z Hi-Z Bypass 1 0 PLLclk PLLclk PLLclkB Test 1 1 Refclk Refclk RefclkB Mode Table 6 shows several supported Pclk and Busclk frequencies, the corresponding A and B dividers required in the DRCG PLL, and the corresponding M and N dividers in the gear ratio logic. The column Ratio gives the Gear Ratio as defined Pclk/Synclk (same as M and N). The column F@PD gives the divided down frequency (in MHz) at the Phase Detector, where F@PD=Pclk/M=Synclk/N. The clock source has three fundamental operating states. Figure 4 shows the state diagram with each transition labelled A through H. Note that the clock source output may NOT be glitch-free during state transitions. Upon powering up the device, the device can enter any state, depending on the settings of the control signals, PwrDnB and StopB. In Power-down mode, the clock source is powered down with the control signal, PwrDnB, equal to 0. The control signals S0 and S1 must be stable before power is applied to the device, and can only be changed in Power-down mode (PwrDnB=0). The reference inputs, V DDR and VDDPD, may remain on or may be grounded during the Power-down mode. Table 5 shows the logic for selecting the Power-down mode, using the PwrDnB input signal. PwrDnB is active LOW (enabled when 0). When PwrDnB is disabled, the DRCG is in its normal mode. When PwrDnB is enabled, the DRCG is put into a powered-off state, and the Clk and ClkB outputs are threestated. Table 6. Examples of Frequencies, Dividers, and Gear Ratios Pclk Refclk Busclk Synclk A B M N Ratio F@PD 67 33 267 67 8 1 2 2 1.0 33 100 50 300 75 6 1 8 6 1.33 12.5 100 50 400 100 8 1 4 4 1.0 25 133 67 267 67 4 1 4 2 2.0 33 133 67 400 100 6 1 8 6 1.33 16.7 VDD Turn-On M VDD Turn-On G J L Test Normal N F B K A E VDD Turn-On VDD Turn-On D Power-Down Clk Stop C Figure 4. Clock Source State Diagram Powered by ICminer.com Electronic-Library Service CopyRight 2003 5 H W134M/W134S The control signals Mult0 and Mult1 can be used in two ways. If they are changed during Power-down mode, then the Powerdown transition timings determine the settling time of the DRCG. However, the Mult0 and Mult1 control signals can also be changed during Normal mode. When the Mult control signals are “hot swapped” in this manner, the Mult transition timings determine the settling time of the DRCG. Table 7. Control Signals for Clock Source States In Clock Stop mode, the clock source is on, but the output is disabled (StopB asserted). The VDDPD reference input may remain on or may be grounded during the Clk Stop mode. The VDDR reference input must remain on during the Clock Stop mode. State PwrDnB StopB Clock Source Output Buffer Power-down 0 X OFF Ground Clock Stop 1 0 ON Disabled Normal 1 1 ON Enabled Figure 5 shows the timing diagrams for the various transitions between states, and Table 8 specifies the latencies of each state transition. Note that these transition latencies assume the following: • Refclk input has settled and meets specification shown in Table 13. • Mult0, Mult1, S0 and S1 control signals are stable. In Normal mode, the clock source is on, and the output is enabled. Table 7 lists the control signals for each state. Timing Diagrams Figure 5. State Transition Timing Diagrams Power-Down Exit and Entry PwrDnB tPOWERDN tPOWERUP Clk/ClkB Output Enable Control tON StopB tSTOP tCLKON tCLKOFF tCLKSETL Clk/ClkB Output clock not specified glitches may occur Clock enabled and glitch free Clock output settled within 50 ps of the phase before disabled Figure 6. Multiply Transition Timing Mult0 and/or Mult1 tMULT Clk/ClkB Powered by ICminer.com Electronic-Library Service CopyRight 2003 6 W134M/W134S Table 8. State Transition Latency Specifications Transition Latency Transition From To Symbol Max. Description A Power-down Normal tPOWERUP 3 ms Time from PwrDnB to Clk/ClkB output settled (excluding tDISTLOCK). C Power-down Clk Stop tPOWERUP 3 ms Time from PwrDnB until the internal PLL and clock has turned ON and settled. K Power-down Test tPOWERUP 3 ms Time from PwrDnB to Clk/ClkB output settled (excluding tDISTLOCK). G VDD ON Normal tPOWERUP 3 ms Time from VDD is applied and settled until Clk/ClkB output settled (excluding tDISTLOCK). H VDD ON Clk Stop tPOWERUP 3 ms Time from VDD is applied and settled until internal PLL and clock has turned ON and settled. M VDD ON Test tPOWERUP 3 ms Time from VDD is applied and settled until internal PLL and clock has turned ON and settled. J Normal Normal tMULT 1 ms Time from when Mult0 or Mult1 changed until Clk/ClkB output resettled (excluding tDISTLOCK). E Clk Stop Normal tCLKON 10 ns Time from StopB until Clk/ClkB provides glitch-free clock edges. E Clk Stop Normal tCLKSETL 20 cycles F Normal Clk Stop tCLKOFF 5 ns Time from StopB Φ to Clk/ClkB output disabled. L Test Normal tCTL 3 ms Time from when S0 or S1 is changed until CLK/CLKB output has resettled (excluding tDISTLOCK). N Normal Test tCTL 3 ms Time from when S0 or S1 is changed until CLK/CLKB output has resettled (excluding tDISTLOCK). B,D Normal or Clk Stop Power-down tPOWERDN 1 ms Time from PwrDnB Φ to the device in Powerdown. Figure 5 shows that the Clk Stop to Normal transition goes through three phases. During tCLKON, the clock output is not specified and can have glitches. For tCLKON< t< tCLKSETL, the clock output is enabled and must be glitch-free. For t>tCLKSETL, the clock output phase must be settled to within Powered by ICminer.com Electronic-Library Service CopyRight 2003 Time from StopB to Clk/ClkB output settled to within 50 ps of the phase before CLK/CLKB was disabled. 50 ps of the phase before the clock output was disabled. At this time, the clock output must also meet the voltage and timing specifications of Table 14. The outputs are in a high-impedance state during the Clk Stop mode. 7 W134M/W134S Table 9. Distributed Loop Lock Time Specification Symbol tDISTLOCK Min. Max. Units 5 ms Description Time from when Clk/ClkB output is settled to when the phase error between SynclkN and PclkM falls within the tERR,PD spec in Table 14. Table 10. Supply and Reference Current Specification Min. Max. Unit IPOWERDOWN Parameter “Supply” current in Power-down state (PwrDnB=0) Description -- 250 µA ICLKSTOP “Supply” current in Clk Stop state (StopB=0) -- 65 mA INORMAL “Supply” current in Normal state (StopB=1,PwrDnB=1) -- 100 mA IREF,PWDN Current at VDDIR or VDDIPD reference pin in Power-down state (PwrDnB=0) -- 50 µA IREF,NORM Current at VDDIR or VDDIPD reference pin in Normal or Clk Stop state (PwrDnB=1) -- 2 mA Min. Max. Unit Table 11 represents stress ratings only, and functional operation at the maximums is not guaranteed. Table 11. Absolute Maximum Ratings Parameter Description VDD, ABS Max. voltage on VDD with respect to ground –0.5 4.0 V VI, ABS Max. voltage on any pin with respect ground –0.5 VDD+0.5 V Table 12 gives the nominal values of the external components and their maximum acceptable tolerance, assuming ZCH=28Ω. Table 12. External Component Values Parameter Description Min. Max. Unit ±5% Ω ±5% Ω RS Serial Resistor 39 RP Parallel Resistor 51 [1] ±10% pF 0.1 µF ±20% CF Edge Rate Filter Capacitor 4–15 CMID AC Ground Capacitor 470 pF Note: 1. Do not populate CF. Leave pads for future use. Powered by ICminer.com Electronic-Library Service CopyRight 2003 8 W134M/W134S Table 13. Operating Conditions Parameter Description Min. Max. Unit VDD Supply Voltage 3.135 3.465 V TA Ambient Operating Temperature 0 70 °C tCYCLE,IN Refclk Input Cycle Time 10 40 ns - 250 ps [2] tJ,IN Input Cycle-to-Cycle Jitter DCIN Input Duty Cycle over 10,000 Cycles 40 60 %tCYCLE FMIN Input Frequency of Modulation 30 33 kHz Modulation Index for Triangular Modulation -- 0.6 % PMIN [3] Modulation Index for Non-Triangular Modulation -- tCYCLE,PD Phase Detector Input Cycle Time at PclkM & SynclkN tERR,INIT Initial Phase error at Phase Detector Inputs DCIN,PD 0.5 [5] % 30 100 ns –0.5 0.5 tCYCLE,PD Phase Detector Input Duty Cycle over 10,000 Cycles 25 75 tCYCLE,PD tI,SR Input Slew Rate (measured at 20%-80% of input voltage) for PclkM, SynclkN, and Refclk 1 4 V/ns CIN,PD Input Capacitance at PclkM, SynclkN, and Refclk[4] - 7 pF - 0.5 pF ∆CIN,PD Input Capacitance matching at PclkM and SynclkN CIN,CMOS Input Capacitance at CMOS pins (excluding PclkM, SynclkN, and Refclk)[4] - 10 pF VIL Input (CMOS) Signal Low Voltage - 0.3 VDD VIH Input (CMOS) Signal High Voltage 0.7 - VDD VIL,R Refclk input Low Voltage - 0.3 VDDIR VIH,R Refclk input High Voltage 0.7 - VDDIR VIL,PD Input Signal Low Voltage for PD Inputs and StopB - 0.3 VDDIPD VIH,PD Input Signal High Voltage for PD Inputs and StopB 0.7 - VDDIPD VDDIR Input Supply Reference for Refclk 1.235 3.465 V [4] VDDIPD Input Supply Reference for PD Inputs 1.235 2.625 V Notes: 2. Refclk jitter measured at VDDIR (nom)/2. 3. If input modulation is used: input modulation is allowed but not required. 4. Capacitance measured at Freq=1 MHz, DC bias=0.9V and VAC<100 mV. 5. The amount of allowed spreading for any non-triangular modulation is determined by the induced downstream tracking skew, which cannot exceed the skew generated by the specified 0.6% triangular modulation. Typically, the amount of allowed non-triangular modulation is about 0.5%. Powered by ICminer.com Electronic-Library Service CopyRight 2003 9 W134M/W134S Table 14. Device Characteristics Parameter Description tCYCLE Clock Cycle Time tJ Cycle-to-Cycle Jitter at Clk/ClkB [6] Total Jitter over 2, 3, or 4 Clock Cycles [6] [7] 266-MHz Cycle-to-Cycle Jitter [7] Min. Max. Unit 2.5 3.75 ns - 60 ps - 100 ps - 100 ps - 160 ps 1 - ps Phase Detector Phase Error for Distributed Loop Measured at PclkMSynclkN (rising edges) (does not include clock jitter) –100 100 ps tERR,SSC PLL Output Phase Error when Tracking SSC –100 100 ps VX,STOP Output Voltage during Clk Stop (StopB=0) 1.1 2.0 V VX Differential Output Crossing-Point Voltage 1.3 1.8 V 0.4 0.6 V - 2.0 V 1.0 - V 12 50 Ω 266-MHz Total Jitter over 2, 3, or 4 Clock Cycles tSTEP Phase Aligner Phase Step Size (at Clk/ClkB) tERR,PD [8] VCOS Output Voltage Swing (p-p single-ended) VOH Output High Voltage VOL Output Low voltage [9] rOUT Output Dynamic Resistance (at pins) IOZ Output Current during Hi-Z (S0 = 0, S1 = 1) - 50 µA IOZ,STOP Output Current during Clk Stop (StopB = 0) - 500 µA DC Output Duty Cycle over 10,000 Cycles 40 60 %tCYCLE tDC,ERR Output Cycle-to-Cycle Duty Cycle Error - 50 ps tR,tF Output Rise and Fall Times (measured at 20%–80% of output voltage) 250 500 ps tCR,CF Difference between Output Rise and Fall Times on the Same Pin of a Single Device (20%–80%) - 100 ps Notes: 6. Output Jitter spec measured at tCYCLE = 2.5 ns. 7. Output Jitter Spec measured at tCYCLE = 3.75 ns. 8. VCOS = VOH–VOL. 9. rOUT = ∆VO/ ∆ IO. This is defined at the output pins. Ordering Information Ordering Code W134M/W134S Package Name H Package Type 24-pin SSOP (150 mils) Document #: 38-00822-A Powered by ICminer.com Electronic-Library Service CopyRight 2003 10 W134M/W134S Layout Example +3.3V Supply FB C4 0.005 µF G 10 µF C3 G VDDIR G G G G G G G VDDIPD 1 2 3 4G 5G 6 7 8G 9 24 23 22 G21 20 19 18 G17 46 15 14 G13 10 11 12 Internal Power Supply Plane FB = Dale ILB1206 - 300 (300Ω @ 100 MHz) G = VIA to GND plane layer All Bypass cap = 0.1 Ceramic XR7 Powered by ICminer.com Electronic-Library Service CopyRight 2003 11 G G G G G W134M/W134S Package Diagram 24-Pin Small Shrink Outline Package (SSOP, 150 mils) © Cypress Semiconductor Corporation, 2000. The information contained herein is subject to change without notice. Cypress Semiconductor Corporation assumes no responsibility for the use of any circuitry other than circuitry embodied in a Cypress Semiconductor product. Nor does it convey or imply any license under patent or other rights. Cypress Semiconductor does not authorize its products for use as critical components in life-support systems where a malfunction or failure may reasonably be expected to result in significant injury to the user. The inclusion of Cypress Semiconductor products in life-support systems application implies that the manufacturer assumes all risk of such use and in doing so indemnifies Cypress Semiconductor against all charges. Powered by ICminer.com Electronic-Library Service CopyRight 2003