SL28PCIe16 EProClock® PCI Express Gen 2 & Gen 3 Clock Generator Features • 25MHz Crystal Input or Clock input • Optimized 100 MHz Operating Frequencies to Meet the Next Generation PCI-Express Gen 2 & Gen 3 • Low power push-pull type differential output buffers • Integrated voltage regulator • Integrated resistors on differential clocks • Six 100-MHz differential SRC clocks • EProClock® Programmable Technology • I2C support with readback capabilities • Triangular Spread Spectrum profile for maximum electromagnetic interference (EMI) reduction • Industrial Temperature -40oC to 85oC • 3.3V Power supply • 32-pin QFN package • Low jitter (<50ps) Pin Configuration Block Diagram XIN XOUT Crystal/ CLKIN PLL 1 (SSC) Divider SRC [5:0] EProClock Technology SCLK SDATA Logic Core VR DOC#: SP-AP-0790 (Rev. 0.3) 400 West Cesar Chavez, Austin, TX 78701 1+(512) 416-8500 1+(512) 416-9669 Page 1 of 12 www.silabs.com SL28PCIe16 32-QFN Pin Definitions Pin No. 1 Name VDD_SRC Type PWR 3.3V Power Supply 2 VDD_SRC PWR 3.3V Power Supply 3 NC NC 4 VSS GND Ground 5 VSS GND Ground 6 SRC0 O, DIF 100MHz True differential serial reference clock 7 SRC0# O, DIF 100MHz Complement differential serial reference clock 8 VDD_SRC PWR Description No Connect. 3.3V Power Supply 9 SRC1 O, DIF 100MHz True differential serial reference clock 10 SRC1# O, DIF 100MHz Complement differential serial reference clock 11 SRC2 O, DIF 100MHz True differential serial reference clock 12 SRC2# O, DIF 100MHz Complement differential serial reference clock 13 VSS_SRC GND Ground 14 VDD_SRC PWR 3.3V Power Supply 15 SRC3# O, DIF 100MHz Complement differential serial reference clock 16 SRC3 O, DIF 100MHz True differential serial reference clock 17 SRC4# O, DIF 100MHz Complement differential serial reference clock 18 SRC4 O, DIF 100MHz True differential serial reference clock 19 VDD_SRC 20 SRC5# O, DIF 100MHz Complement differential serial reference clock PWR 21 SRC5 O, DIF 100MHz True differential serial reference clock 22 VSS_SRC 23 SCLK I 24 SDATA I/O 25 XOUT O 25.00MHz Crystal output, Float XOUT if using only CLKIN (Clock input) 26 XIN / CLKIN I 25.00MHz Crystal input or 3.3V, 25MHz Clock Input 27 VSS_CORE GND 28 NC GND NC 3.3V Power Supply Ground SMBus compatible SCLOCK SMBus compatible SDATA Ground No Connect. 29 VDD_CORE PWR 3.3V Power Supply 30 VDD_SRC PWR 3.3V Power Supply 31 NC 32 VSS_SRC NC GND No Connect. Ground EProClock® Programmable Technology EProClock® is the world’s first non-volatile programmable clock. The EProClock® technology allows board designer to promptly achieve optimum compliance and clock signal integrity; historically, attainable typically through device and/or board redesigns. - Differential skew control on true or compliment or both EProClock® technology can be configured through SMBus or hard coded. - Program Internal or External series resistor on single-ended clocks - Differential duty cycle control on true or compliment or both - Differential amplitude control - Differential and single-ended slew rate control Features: - Program different spread profiles - > 4000 bits of configurations - Program different spread modulation rate - Can be configured through SMBus or hard coded - Custom frequency sets DOC#: SP-AP-0790 (Rev. 0.3) Page 2 of 12 SL28PCIe16 Serial Data Interface Data Protocol To enhance the flexibility and function of the clock synthesizer, a two-signal serial interface is provided. Through the Serial Data Interface, various device functions, such as individual clock output buffers are individually enabled or disabled. The registers associated with the Serial Data Interface initialize to their default setting at power-up. The use of this interface is optional. Clock device register changes are normally made at system initialization, if any are required. The interface cannot be used during system operation for power management functions. The clock driver serial protocol accepts byte write, byte read, block write, and block read operations from the controller. For block write/read operation, access the bytes in sequential order from lowest to highest (most significant bit first) with the ability to stop after any complete byte is transferred. For byte write and byte read operations, the system controller can access individually indexed bytes. The offset of the indexed byte is encoded in the command code described in Table 1. The block write and block read protocol is outlined in Table 2 while Table 3 outlines byte write and byte read protocol. The slave receiver address is 11010010 (D2h). Table 1. Command Code Definition Bit 7 Description 0 = Block read or block write operation, 1 = Byte read or byte write operation (6:0) Byte offset for byte read or byte write operation. For block read or block write operations, these bits should be '0000000' Table 2. Block Read and Block Write Protocol Block Write Protocol Bit 1 8:2 9 10 18:11 19 27:20 28 36:29 37 45:38 Description Start Block Read Protocol Bit 1 Slave address–7 bits Write 8:2 9 Acknowledge from slave Command Code–8 bits 10 18:11 Description Start Slave address–7 bits Write Acknowledge from slave Command Code–8 bits Acknowledge from slave 19 Acknowledge from slave Byte Count–8 bits 20 Repeat start Acknowledge from slave Data byte 1–8 bits Acknowledge from slave Data byte 2–8 bits 27:21 Read = 1 29 Acknowledge from slave 37:30 46 Acknowledge from slave .... Data Byte /Slave Acknowledges .... Data Byte N–8 bits .... Acknowledge from slave .... Stop Slave address–7 bits 28 38 46:39 47 55:48 Byte Count from slave–8 bits Acknowledge Data byte 1 from slave–8 bits Acknowledge Data byte 2 from slave–8 bits 56 Acknowledge .... Data bytes from slave / Acknowledge .... Data Byte N from slave–8 bits .... NOT Acknowledge .... Stop Control Registers Table 3. Byte Read and Byte Write Protocol Byte Write Protocol Bit 1 Description Start DOC#: SP-AP-0790 (Rev. 0.3) Byte Read Protocol Bit 1 Description Start Page 3 of 12 SL28PCIe16 Table 3. Byte Read and Byte Write Protocol 8:2 Slave address–7 bits 8:2 Slave address–7 bits 9 Write 9 Write 10 Acknowledge from slave 10 Acknowledge from slave 18:11 19 27:20 Command Code–8 bits 18:11 Acknowledge from slave 19 Data byte–8 bits 20 28 Acknowledge from slave 29 Stop 27:21 Command Code–8 bits Acknowledge from slave Repeated start Slave address–7 bits 28 Read 29 Acknowledge from slave 37:30 Data from slave–8 bits 38 NOT Acknowledge 39 Stop Byte 0: Control Register 0 Bit @Pup Name Description 7 0 RESERVED RESERVED 6 0 RESERVED RESERVED 5 1 Spread Enable 4 0 RESERVED RESERVED 3 0 RESERVED RESERVED 2 0 RESERVED RESERVED 1 0 RESERVED RESERVED 0 0 RESERVED RESERVED Enable spread for SRC outputs 0=Disable, 1= -0.5% Byte 1: Control Register 1 Bit @Pup Name Description 7 0 RESERVED 6 1 SRC0_OE 5 0 RESERVED RESERVED 4 0 RESERVED RESERVED 3 1 SRC1_OE 2 1 RESERVED RESERVED 1 0 RESERVED RESERVED 0 0 RESERVED RESERVED RESERVED Output enable for SRC0 0 = Output Disabled, 1 = Output Enabled Output enable for SRC1 0 = Output Disabled, 1 = Output Enabled Byte 2: Control Register 2 Bit @Pup Name 7 0 RESERVED RESERVED 6 0 RESERVED RESERVED 5 0 RESERVED RESERVED 4 0 RESERVED RESERVED 3 0 RESERVED RESERVED 2 0 RESERVED RESERVED DOC#: SP-AP-0790 (Rev. 0.3) Description Page 4 of 12 SL28PCIe16 Byte 2: Control Register 2 (continued) Bit @Pup Name Description 1 0 RESERVED RESERVED 0 0 RESERVED RESERVED Byte 3: Control Register 3 Bit @Pup Name Description 7 1 SRC4_OE Output enable for SRC4 0 = Output Disabled, 1 = Output Enabled 6 1 SRC5_OE Output enable for SRC5 0 = Output Disabled, 1 = Output Enabled 5 0 RESERVED RESERVED 4 0 RESERVED RESERVED 3 0 RESERVED RESERVED 2 0 RESERVED RESERVED 1 0 RESERVED RESERVED 0 0 RESERVED RESERVED Byte 4: Control Register 4 Bit @Pup Name 7 0 RESERVED RESERVED Description 6 0 RESERVED RESERVED 5 1 RESERVED RESERVED 4 0 RESERVED RESERVED 3 0 RESERVED RESERVED 2 0 RESERVED RESERVED 1 0 RESERVED RESERVED 0 0 RESERVED RESERVED Byte 5: Control Register 5 Bit @Pup Name 7 0 RESERVED RESERVED Description 6 0 RESERVED RESERVED 5 0 RESERVED RESERVED 4 1 RESERVED RESERVED 3 0 RESERVED RESERVED 2 0 RESERVED RESERVED 1 0 RESERVED RESERVED 0 0 RESERVED RESERVED Byte 6: Control Register 6 Bit @Pup Name 7 0 SRC[5:4]_AMP1 6 1 SRC[5:4]_AMP0 DOC#: SP-AP-0790 (Rev. 0.3) Description SRC[5:4] amplitude adjustment 00= 700mV, 01=800mV, 10=900mV, 11= 1000mV Page 5 of 12 SL28PCIe16 Byte 6: Control Register 6 5 0 SRC[3:1]_AMP1 SRC[3:1] amplitude adjustment 00= 700mV, 01=800mV, 10=900mV, 11= 1000mV 4 1 SRC[3:1]_AMP0 3 0 RESERVED RESERVED 2 1 RESERVED RESERVED 1 0 SRC0_AMP1 0 1 SRC0_AMP0 SRC0 amplitude adjustment 00= 700mV, 01=800mV, 10=900mV, 11= 1000mV Byte 7: Vendor ID Bit @Pup Name 7 0 Rev Code Bit 3 Revision Code Bit 3 Description 6 0 Rev Code Bit 2 Revision Code Bit 2 5 0 Rev Code Bit 1 Revision Code Bit 1 4 1 Rev Code Bit 0 Revision Code Bit 0 3 1 Vendor ID bit 3 Vendor ID Bit 3 2 0 Vendor ID bit 2 Vendor ID Bit 2 1 0 Vendor ID bit 1 Vendor ID Bit 1 0 0 Vendor ID bit 0 Vendor ID Bit 0 Byte 8: Control Register 8 Bit @Pup Name Description 7 0 RESERVED RESERVED 6 0 RESERVED RESERVED 5 0 RESERVED 4 0 BC4 3 1 BC3 2 1 BC2 1 1 BC1 0 1 BC0 RESERVED Byte count register for block read operation. The default value for Byte count is 9. In order to read beyond Byte 9, the user should change the byte count limit.to or beyond the byte that is desired to be read. Byte 9: Control Register 9 Bit @Pup Name 7 0 RESERVED 6 1 SRC3_OE Output enable for SRC3 0 = Output Disabled, 1 = Output Enabled 5 1 SRC2_OE Output enable for SRC2 0 = Output Disabled, 1 = Output Enabled 4 0 RESERVED RESERVED 3 0 RESERVED RESERVED 2 0 RESERVED RESERVED 1 0 RESERVED RESERVED 0 1 RESERVED RESERVED DOC#: SP-AP-0790 (Rev. 0.3) Description RESERVED Page 6 of 12 SL28PCIe16 Absolute Maximum Conditions Parameter Description Condition Min. Max. Unit – 4.6 V –0.5 4.6 VDC –65 150 °C Functional –40 85 °C Commercial Temperature, Operating Ambient Functional 0 85 °C VDD_3.3V Main Supply Voltage VIN Input Voltage Relative to VSS TS Temperature, Storage Non-functional TA Industrial Temperature, Operating Ambient TA Functional TJ Temperature, Junction Functional – 150 °C ØJC Dissipation, Junction to Case JEDEC (JESD 51) – 20 °C/ W ØJA Dissipation, Junction to Ambient JEDEC (JESD 51) – 60 °C/ W ESDHBM ESD Protection (Human Body Model) JEDEC (JESD 22 - A114) 2000 – V UL-94 Flammability Rating UL (Class) V–0 Multiple Supplies: The Voltage on any input or I/O pin cannot exceed the power pin during power-up. Power supply sequencing is NOT required. DC Electrical Specifications Parameter Description VDD core 3.3V Operating Voltage VIH 3.3V Input High Voltage VIL 3.3V Input Low Voltage Condition Min. Max. Unit 3.135 3.465 V Single-Ended Clock 2.0 VDD + 0.3 V Single-Ended Clock VSS – 0.3 0.8 V 3.3 ± 5% VIHI2C Input High Voltage SDATA, SCLK 2.2 – V VILI2C Input Low Voltage SDATA, SCLK – 1.0 V IIH Input High Leakage Current Except internal pull-down resistors, 0 < VIN < VDD – 5 A Except internal pull-up resistors, 0 < VIN < VDD –5 – A 0.7 0.9 V 3.3V Output Low Voltage (DIFF) – 0.4 V High-impedance Output Current –10 10 A CIN Input Pin Capacitance 1.5 5 pF COUT Output Pin Capacitance 6 pF LIN Pin Inductance IDD_3.3V Dynamic Supply Current IIL Input Low Leakage Current VOH 3.3V Output High Voltage (DIFF) VOL IOZ DOC#: SP-AP-0790 (Rev. 0.3) Differential clocks with 7” traces and 2pF load. – 7 nH – 65 mA Page 7 of 12 SL28PCIe16 AC Electrical Specifications Parameter Description Condition Min. Max. Unit – 250 ppm Crystal LACC Long-term Accuracy Measured at VDD/2 differential Clock Input TDC CLKIN Duty Cycle Measured at VDD/2 47 53 % TR/TF CLKIN Rise and Fall Times Measured between 0.2VDD and 0.8VDD 0.5 4.0 V/ns TCCJ CLKIN Cycle to Cycle Jitter Measured at VDD/2 – 250 ps TLTJ CLKIN Long Term Jitter Measured at VDD/2 – 350 ps VIH Input High Voltage XIN / CLKIN pin 2 VDD+0.3 V VIL Input Low Voltage XIN / CLKIN pin – 0.8 V IIH Input High Current XIN / CLKIN pin, VIN = VDD – 35 uA IIL Input Low Current XIN / CLKIN pin, 0 < VIN <0.8 –35 – uA TDC SRC Duty Cycle Measured at 0V differential SRC at 0.7V 45 55 % 10.0010 ns TPERIOD 100 MHz SRC Period Measured at 0V differential at 0.1s 9.99900 TPERIODSS 100 MHz SRC Period, SSC Measured at 0V differential at 0.1s 10.02406 10.02607 ns TPERIODAbs 100 MHz SRC Absolute Period 10.1260 ns Measured at 0V differential at 1 clock 9.87400 TPERIODSSAbs 100 MHz SRC Absolute Period, SSC Measured at 0V differential at 1 clock 9.87406 10.1762 ns TCCJ SRC Cycle to Cycle Jitter Measured at 0V differential – 50 ps RMSGEN1 Output PCIe* Gen1 REFCLK phase jitter BER = 1E-12 (including PLL BW 8 - 16 MHz, ζ = 0.54, Td=10 ns, Ftrk=1.5 MHz) 0 108 ps Output PCIe* Gen2 REFCLK phase jitter Includes PLL BW 8 - 16 MHz, Jitter Peaking = 3dB, ζ = 0.54, Td=10 ns), Low Band, F < 1.5MHz 0 3.0 ps Output PCIe* Gen2 REFCLK phase jitter Includes PLL BW 8 - 16 MHz, Jitter Peaking = 3dB, ζ = 0.54, Td=10 ns), Low Band, F < 1.5MHz 0 3.1 ps Includes PLL BW 2 - 4 MHz, CDR = 10MHz) Measured at 0V differential 0 1.0 ps LACC Output phase jitter impact – PCIe* Gen3 SRC Long Term Accuracy – 100 ppm T R / TF SRC Rising/Falling Slew Rate Measured differentially from ±150 mV 2.5 8 V/ns VHIGH Voltage High 1.15 V VLOW Voltage Low –0.3 – V VOX Crossing Point Voltage at 0.7V Swing 300 550 mV – 1.8 ms 10.0 – ns RMSGEN2 RMSGEN2 RMSGEN3 ENABLE/DISABLE and SET-UP TSTABLE Clock Stabilization from Power-up TSS Stopclock Set-up Time DOC#: SP-AP-0790 (Rev. 0.3) Page 8 of 12 SL28PCIe16 Test and Measurement Set-up This diagram shows the test load configuration for the differential clock signals Figure 1. 0.7V Differential Load Configuration Figure 2. Differential Measurement for Differential Output Signals (for AC Parameters Measurement) DOC#: SP-AP-0790 (Rev. 0.3) Page 9 of 12 SL28PCIe16 Figure 3. Single-ended Measurement for Differential Output Signals (for AC Parameters Measurement) DOC#: SP-AP-0790 (Rev. 0.3) Page 10 of 12 SL28PCIe16 Ordering Information Part Number Package Type Product Flow Lead-free SL28PCIe16ALC 32-pin QFN Commercial, 0 to 85C SL28PCIe16ALCT 32-pin QFN–Tape and Reel Commercial, 0 to 85C SL28PCIe16ALI 32-pin QFN Industrial, -40 to 85C SL28PCIe16ALIT 32-pin QFN–Tape and Reel Industrial, -40 to 85C Package Diagrams 32-Lead QFN 5 x 5mm DOC#: SP-AP-0790 (Rev. 0.3) Page 11 of 12 SL28PCIe16 Document History Page Document Title: SL28PCIe16 PC EProClock® PCI Express Gen 2 & Gen 3 Clock Generator DOC#: SP-AP-0790 (Rev. 0.3) REV. Issue Date Orig. of Change AA 11/15/10 JMA Initial Release AA 12/15/10 TRP 1. Updated Control Registers 2. Updated VOH/VOL spec 3. Removed IDD_PD spec 4. Updated foot note AB 1/13/11 TRP 1. Updated IDD current 2. Updated Byte8 default 3. Removed skew spec Description of Change The information in this document is believed to be accurate in all respects at the time of publication but is subject to change without notice. Silicon Laboratories assumes no responsibility for errors and omissions, and disclaims responsibility for any consequences resulting from the use of information included herein. Additionally, Silicon Laboratories assumes no responsibility for the functioning of undescribed features or parameters. Silicon Laboratories reserves the right to make changes without further notice. Silicon Laboratories makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does Silicon Laboratories assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation consequential or incidental damages. Silicon Laboratories products are not designed, intended, or authorized for use in applications intended to support or sustain life, or for any other application in which the failure of the Silicon Laboratories product could create a situation where personal injury or death may occur. Should Buyer purchase or use Silicon Laboratories products for any such unintended or unauthorized application, Buyer shall indemnify and hold Silicon Laboratories harmless against all claims and damages. DOC#: SP-AP-0790 (Rev. 0.3) Page 12 of 12