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Rev 2.3, July 9, 2010 Page 1 of 10 400 West Cesar Chavez, Austin, TX 78701 1+(512) 416-8500 1+(512) 416-9669 www.silabs.com SL38000-15AH Key Features

  • REFOUT=25.000MHz
  • CLK1=12.000MHz
  • CLK2=125.000MHz
  • SSCLK1=133.333MHz with +/-0.25% spread option
  • SSCLK2=50.000MHz with +0.5% spread option
  • VDD=VDDO=3.3V +/-10% power supply
  • 25.000MHz external crystal
  • Integrated internal voltage regulator
  • PD# control function
  • OE control function (CLK1 only)
  • SSON enable/disable function function for SSCLK1/2
  • Programmable CL at XIN and XOUT pins
  • Programmable output rise and fall times
  • 28-pin TSSOP package with commercial and industrial temperature range available

Applications

  • Broadband Home Router
  • General Purpose Frequency Synthesising

Description

The SL38000-15AH a fully integrated 4 PLL low power Clock Generator with a Spread Spectrum Clock (SSC) function used for reducing Electromagnetic Interference (EMI) and general purpose frequency synthesizing. The product is designed using SpectraLinear proprietary phase- locked loop (PLL) and SSC technology to synthesize and modulate the input clock. The modulated clock can significantly reduce the measured EMI levels, leading to the compliance with regulatory agency requirements. SSCLK1 output provides +/-0.25% center-spread and SSCLK2 output +0.5% up-spread. If SSON=1 both spreads are on. Spreads can be turned off (no-spread) if SSON=0. The SL38000-15AH operates from 3.3V power supply. The product is offered in 28-pin TSSOP package with both commercial and industrial temperature grades available. Benefits

  • Eleminates the need for XOs and Xtals
  • EMI Reduction
  • Fast time-to-market
  • Cost Reduction
  • Reduction of PCB layers Block Diagram PLL-1 PLL-2 SS-PLL-3 SS-PLL-4 Input Mux and Control Logic Output Drivers with Multi Function I/O and Output Drivers Drive Strength Control XTAL OSCILLATOR (XO) SS Logic Control Mux and Div Control MEMORY Configuration Configuration Logic XIN XOUT CLK1 (12.000MHz) SSCLK1 (133.333MHz) SSCLK2 (50.000MHz) OE PD# VSS VDDO1/2/3 Voltage Regulators VDD VSS To XO, PLLs and Core SSON# REFOUT1 (25.000MHz) CLK2 (125.000MHz) 4-PLL Clock Generator with SSC

Table 1. SSCLK1 and SSCLK2 versus SSON# Operation Table 2. Output Enable (OE) Operation

1 Clock is Enabled

0 Clock is Disabled (Hi-Z)

Table 3. Power Down (PD#) Operation

1 Normal Operation

0 Power Down

Rev 2.3, July 9, 2010 Page 3 of 10 SL38000-15AH Pin Description Pin Number Pin Name Pin Type Pin Description 1 XIN/CLKIN Input External crystal oscillator input. XIN=25.000MHz. If crystal with CL=18pF is used no external crystal load capacitors are needed. See Note-2 below. 2 OE Input Output enable for CLK1 (12.000MHz) pin. OE=1 CLK1 is enabled. OE=0 CLK1 is disabled. Refer to Table 2. Weakly pulled-up to VDD (200kΩ-typ). 3 CLK2 Output 125.000MHz clock output. No Spread. 4,12,13, 15,18,25 N/C N/A No connect (leave these pins floating). 5 VDDO1 Power Power pin for SSCLK1=133.333MHz. 3.3V+/-10%. Power supply ramp on this pin should be the same as VDD power ramp on pins 6, 26 and 27. See Note-1 below. 6,26,27 VDD Power 3.3V+/-10%. 7,8,9,10, 20,21 VSS Power Power supply ground for VDD and VDDO pins. 11 REFOUT Output 25.000MHz. (Same as crystal input frequency) 14 SSCLK1 Output 133.333MHz clock output with spread option. Spread is off if SSON=0. Spread is on if SSON=1. Refer to Table 1. 16 SSCLK2 Output 50.000MHz clock output with spread option. Spread is off if SSON=0. Spread is on if SSON=1. Refer to Table 1. 17 SSON Input Spread control pin for SSCLK1 (133.333MHz) and SSCLK2 (50.000MHz) clocks. If SSON=1 spread is on. If SSON=0 spread is 0% (no spread). Refer to Table 1 for spread % values. Weakly pulled-down to VSS (200kΩ-typ). SSON is powered by VDDO3 and SSON=1=VDDO3=2.5V. 19 CLK1 Output 12.000MHz clock output. No Spread. 22 VDDO3 Power Power pin for CLK1=12.000MHz. 3.3V+/-10%. Power supply ramp on this pin should be the same as VDD power ramp on pins 6, 26 and 27. See Note-1 below. 23 VDDO2 Power Power pin for SSCLK2=50.000MHz. 3.3V+/-10%. Power supply ramp on this pin should be the same as VDD power ramp on pins 6, 26 and 27. See Note-1 below. 24 PD# Input Power down control pin. PD#=1 is normal operation. Device is turned off if PD#=0. Refer to Table 3. Weakly pulled-up to VDD (200kΩ-typ). 28 XOUT Output External crystal output. If crystal with CL=18pF is used no external crystal load capacitors are needed. See Note-2 below. Note-1: VDDO≤VDD at all times or all VDD and VDDO pins must be connected to same common VDD power supply. Note-2: Xin and Xout pin capacitances are programmed as 34pF. Including 2pF parasitic PCB capacitances at each pin, the total capacitance value becomes 36pF. If a crystal with 18pF is used, no external capacitance is required since these capacitance values matches the crystal CL=18pF requirement for nominal +/-0ppm crystal accuracy.

Rev 2.3, July 9, 2010 Page 4 of 10 SL38000-15AH Absolute Maximum Ratings Description Condition Min Max Unit Supply voltage, VDD VDD -0.5 4.1 V Supply voltage, VDDO VDDO≤VDD - VDD V All Inputs and Outputs -0.5 VDD+0.5 V Ambient Operating Temperature In operation, C-Grade 0 70 °C Ambient Operating Temperature In operation, I-Grade -40 85 °C Storage Temperature No power is applied -65 150 °C Junction Temperature In operation, power is applied - 125 °C Soldering Temperature - 260 °C ESD Rating (Human Body Model) JEDEC22-A114D -3,000 3,000 V ESD Rating (Machine Model) JEDEC22-A115D -200 200 V Unless otherwise stated VDD=VDDO==3.3V+/-10%, CL=15pF and Ambient Temperature range 0 to +70Deg C Description Symbol Condition Min Typ Max Unit Operating Voltage VDD VDD+/-10% 2.97 3.3 3.63 V Operating Voltage VDDO VDDO1/2/3, VDDO≤VDD 2.97 3.3 3.63 V Input Low Voltage VIL CMOS Level, PD#, OE, SSON 0 - 0.3VDD V Input High Voltage VIH CMOS Level, Pins programmed as PD#, OE or SSON 0.7VDD - VDD V Output High Voltage VOH1 IOH=-4mA , REFOUT and CLK1/2, SSCLK1/2 if VDDO=VDD VDD-0.5 - - V Output Low Voltage VOL1 IOL=4mA , REFOUT, CLK1/2, SSCLK1/2 - - 0.5 V Input High Current IIH VIN=VDD, Pins 2, 3 and 24 -50 - 50 μA Input Low Current IIL VIN=GND, Pins 2, 3 and 24 -50 - 50 μA Pull-up or Down Resistors RPU/D Pins 2, 3 and 24 - 200 - kΩ Operating Supply Current IDD Xin=25.000MHz and all 5 clocks are active and CL=0, VDD=3.3V - 28 38 mA Standby Current ISBC PD#=GND - 650 - μA Output Leakage Current IOL OE=GND at CLKOUT pins -10 - 10 μA Input Capacitance Cin Cout Pins 1 and 28 (On-chip CXin and CXout pin capacitances) - 34 - pF Input Capacitance CIN2 Pins 2, 17 and 24 (OE, SSON and PD#) - 4 6 pF Load Capacitance CL All CLKOUT outputs - - 15 pF

Rev 2.3, July 9, 2010 Page 5 of 10 SL38000-15AH Unless otherwise stated VDD=VDDO=3.3V+/-10%, CL=15pF and Ambient Temperature range 0 to +70 Deg C Parameter Symbol Condition Min Typ Max Unit Input Frequency Range FIN1 Crystal Resonator - 25.000 - MHz Output Frequency Range FOUT1 REFOUT, Pin 11, PD#=1 - 25.000 - MHz Output Frequency Range FOUT2 CLK1, Pin 19, OE=1, PD#=1 - 12.000 - MHz Output Frequency Range FOUT3 CLK2, Pin 3, PD#=1 - 125.000 - MHz Output Frequency Range FOUT4 SSCLK1, Pin 14, SSON=0, PD#=1 - 133.333 - MHz Output Frequency Range FOUT5 SSCLK2, Pin 16, SSON=0, PD#=1 - 50.000 - MHz Output Duty Cycle DC1 REFCLK, CLK1/2 and SSCLK1/2 45 50 55 % Clock Accuracy PPM All clocks (Pins 3, 11, 14, 16, 19 ) -1 0 1 ppm Rise/Fall Time Tr/f-1 REFOUT, Pin 11, CL=10pF, VDD=3.3V - 3.2 4.0 ns Rise/Fall Time Tr/f-2 CLK1, Pin 19, CL=10pF, VDD02=3.3V - 0.8 1.4 ns Rise/Fall Time Tr/f-3 CLK2, Pin 3, CL=10pF, VDD02=3.3V - 0.8 1.4 ns Rise/Fall Time Tr/f-4 SSCLK1, Pin 14, CL=10pF, VDD01=3.3V - 0.8 1.4 ns Rise/Fall Time Tr/f-5 SSCLK2, Pin 16, CL=10pF, VDD03=3.3V - 1.6 2.4 ns Cycle-to-Cycle Jitter CCJ1 REFOUT=25.000MHz, CL=10pF, Pins 11 - 40 - ps- rms Cycle-to-Cycle Jitter CCJ2 CLK1=12.000MHz, CL=10pF Pin 19 - 22 - ps- rms Cycle-to-Cycle Jitter CCJ3 CLK2=125.000MHz, CL=10pF Pin 3 - 18 - ps- rms Cycle-to-Cycle Jitter CCJ4 SSCLK2=50.000MHz, SSON=1, CL=10pF, Pin 16 - 40 - ps- rms Cycle-to-Cycle Jitter CCJ5 SSCLK1=133.333MHz, SSON=1, CL=10pF, Pin 14 - 18 - ps- rms Power-down Time tPD Time from PD# falling edge to Hi-Z at outputs (Asynchronous) - 150 350 ns Power-up Time (Crystal) tPU1 Time from VDD=3.3V rising edge to valid output frequency (Asynchronous) - 5.0 8.0 ms Power-up time (PD#) tPU2 Time from PD# rising edge to valid frequency at outputs (Asynchronous) 0.25 2.0 ms Output Enable Time tOE Time from OE rising edge to valid clock at Pin-19 (Asynchronous) - 250 400 ns

Rev 2.3, July 9, 2010 Page 6 of 10 SL38000-15AH Output Disable Time tOD Time from OE falling edge to Hi-Z at Pin-19 (Asynchronous) - 200 350 ns Power Supply Ramp tPSR Time for VDD and VDDO reaching minimum specified value and monolithic power supply ramp 0 - 12 ms Spread Percent SPR1 Center Spread, SSCLK1, Pin 14 SSON=1 and PD#=1 - +/-0.25 - % Spread Percent SPR1 Up Spread, SSCLK2, Pin 16 SSON=1 and PD#=1 - +0.5 - % Spread Percent Variation ΔSS% Variation of programmed Spread % -15 - 15 % Modulation Frequency FMOD All spread spectrum clocks when spread is on - 38.6 - kHz Unless otherwise stated VDD=VDDO==3.3V+/-10%, CL=15pF and Ambient Temperature range -40 to +85 Deg C Description Symbol Condition Min Typ Max Unit Operating Voltage VDD VDD+/-10% 2.97 3.3 3.63 V Operating Voltage VDDO VDDO1/2/3, VDDO≤VDD 2.97 3.3 3.63 V Input Low Voltage VIL CMOS Level, PD#, OE, SSON 0 - 0.3VDD V Input High Voltage VIH CMOS Level, Pins programmed as PD#, OE or SSON 0.7VDD - VDD V Output High Voltage VOH1 IOH=-4mA , REFOUT and CLK1/2, SSCLK1/2 if VDDO=VDD VDD-0.5 - - V Output Low Voltage VOL1 IOL=4mA , REFOUT, CLK1/2, SSCLK1/2 - - 0.5 V Input High Current IIH VIN=VDD, Pins 2, 3 and 24 -50 - 50 μA Input Low Current IIL VIN=GND, Pins 2, 3 and 24 -50 - 50 μA Pull-up or Down Resistors RPU/D Pins 2, 3 and 24 - 200 - kΩ Operating Supply Current IDD Xin=25.000MHz and all 5 clocks are active and CL=0, VDD=3.3V - 30 40 mA Standby Current ISBC PD#=GND - 650 - μA Output Leakage Current IOL OE=GND at CLKOUT pins -10 - 10 μA Input Capacitance Cin Cout Pins 1 and 28 (On-chip CXin and CXout pin capacitances) - 34 - pF Input Capacitance CIN2 Pins 2, 17 and 24 (OE, SSON and PD#) - 4 6 pF Load Capacitance CL All CLKOUT outputs - - 15 pF

Rev 2.3, July 9, 2010 Page 7 of 10 SL38000-15AH Unless otherwise stated VDD=VDDO=3.3V+/-10%, CL=15pF and Ambient Temperature range -40 to +85 Deg C Parameter Symbol Condition Min Typ Max Unit Input Frequency Range FIN1 Crystal Resonator - 25.000 - MHz Output Frequency Range FOUT1 REFOUT, Pin 11, PD#=1 - 25.000 - MHz Output Frequency Range FOUT2 CLK1, Pin 19, OE=1, PD#=1 - 12.000 - MHz Output Frequency Range FOUT3 CLK2, Pin 3, PD#=1 - 125.000 - MHz Output Frequency Range FOUT4 SSCLK1, Pin 14, SSON=0, PD#=1 - 133.333 - MHz Output Frequency Range FOUT5 SSCLK2, Pin 16, SSON=0, PD#=1 - 50.000 - MHz Output Duty Cycle DC1 REFCLK, CLK1/2 and SSCLK1/2 45 50 55 % Clock Accuracy PPM All clocks (Pins 3, 11, 14, 16, 19 ) -1 0 1 ppm Rise/Fall Time Tr/f-1 REFOUT, Pin 11, CL=10pF, VDD=3.3V - 1.4 4.0 ns Rise/Fall Time Tr/f-2 CLK1, Pin 19, CL=10pF, VDD02=3.3V - 0.8 1.5 ns Rise/Fall Time Tr/f-3 CLK2, Pin 3, CL=10pF, VDD02=3.3V - 0.9 1.6 ns Rise/Fall Time Tr/f-4 SSCLK1, Pin 14, CL=10pF, VDD01=3.3V - 0.8 1.6 ns Rise/Fall Time Tr/f-5 SSCLK2, Pin 16, CL=10pF, VDD03=3.3V - 1.6 2.4 ns Cycle-to-Cycle Jitter CCJ1 REFOUT=25.000MHz, CL=10pF, Pins 11 - 40 - ps- rms Cycle-to-Cycle Jitter CCJ2 CLK1=12.000MHz, CL=10pF Pin 19 - 22 - ps- rms Cycle-to-Cycle Jitter CCJ3 CLK2=125.000MHz, CL=10pF Pin 3 - 18 - ps- rms Cycle-to-Cycle Jitter CCJ4 SSCLK2=50.000MHz, SSON=1, CL=10pF, Pin 16 - 40 - ps- rms Power-down Time tPD Time from PD# falling edge to Hi-Z at outputs (Asynchronous) - 150 350 ns Power-up Time (Crystal) tPU1 Time from VDD=3.3V rising edge to valid output frequency (Asynchronous) - 5.0 8.0 ms Power-up time (PD#) tPU2 Time from PD# rising edge to valid frequency at outputs (Asynchronous) 0.25 2.0 ms Output Enable Time tOE Time from OE rising edge to valid clock at Pin-19 (Asynchronous) - 250 400 ns Output Disable Time tOD Time from OE falling edge to Hi-Z at Pin-19 (Asynchronous) - 200 350 ns

Rev 2.3, July 9, 2010 Page 8 of 10 SL38000-15AH Power Supply Ramp tPSR Time for VDD and VDDO reaching minimum specified value and monolithic power supply ramp 0 - 12 ms Spread Percent SPR1 Center Spread, SSCLK1, Pin 14 SSON=1 and PD#=1 - +/-0.25 - % Spread Percent SPR1 Up Spread, SSCLK2, Pin 16 SSON=1 and PD#=1 - +0.5 - % Spread Percent Variation ΔSS% Variation of programmed Spread % 15 - 15 % Modulation Frequency FMOD All spread spectrum clocks when spread is on - 38.6 - kHz External Components & Design Considerations Decoupling Capacitor: A decoupling capacitor of 0.1μF must be used between all VDD or VDDO and VSS pins on PCB. Place the capacitor on the component side of the PCB as close to the VDD or VDDO pins as possible. The PCB trace to the VDD or VDDO pins and to the GND via should be kept as short as possible Do not use vias between the decoupling capacitor and the VDD or VDDO pins. Series Termination Resistor: A series termination resistor is recommended if the distance between the outputs (SSCLK, CLK or REFCLK pins) and the load is over 1 ½ inch. The nominal impedance of the all clock outputs are about 25 Ω. Use 20 Ω resistor in series with the output to terminate 50Ω trace impedance and place 20 Ω resistor as close to the SSCLK output as possible. Crystal and Crystal Load: Use only parallel resonant fundamental crystals. DO NOT USE higher overtone crystals. To meet the crystal initial accuracy specification (in ppm); the internal on-chip programmable capacitors PCin and PCout must be programmed to match the crystal load requirement. These values are given by the formula below: PCin(pF) =PCout(pF)= [(CL(pF) – Cp(pF)/2)] x 2 Where CL is crystal load capacitor as given by the crystal datasheet and Cp(pF) is the compensation factor for the total parasitic capacitance at XIN or XOUT pin including PCB related parasitic capacitance. As an example; if a crystal with CL=18pF is used and Cp=2pF, by using the above formula, PCin=PCout=[(18-(2/2)] x 2 = 34pF. Programming PCin and PCout to 34pF assures that this crystal sees an equivalent load of 18pF and no other external crystal load capacitor is needed. Deviating from the crystal load specification could cause an increase in frequency accuracy in ppm.

Rev 2.3, July 9, 2010 Page 9 of 10 SL38000-15AH Package Outline and Package Dimensions 28-Pin TSSOP Package

Rev 2.3, July 9, 2010 Page 10 of 10 SL38000-15AH

Ordering Information

[1] Ordering Number [2] Marking Shipping Package Package Temperature SL38000ZC-15AH SL38000ZC-15AH Tube 28-pin TSSOP 0 to 70°C SL38000ZC-15AHT SL38000ZC-15AH Tape and Reel 28-pin TSSOP 0 to 70°C SL38000ZI-15AH SL38000ZI-15AH Tube 28-pin TSSOP -40 to 85°C SL38000ZI-15AHT SL38000ZI-15AH Tape and Reel 28-pin TSSOP -40 to 85°C Note: 1. All SLI products are RoHS compliant. 2. “SL38000ZC/I-15AH” is “Hard Coded” version of SL38000ZC/I-15A programmable product. 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 undes cribed features or parameters. Silicon Laboratories reserves t he 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.