PRELIMINARY Integrated Circuit Systems, Inc. ICS8421004I-01 FEMTOCLOCKS™ CRYSTAL-TOHSTL FREQUENCY SYNTHESIZER GENERAL DESCRIPTION FEATURES The ICS8421004I-01 is a 4 output HSTL Synthesizer optimized to generate Ethernet HiPerClockS™ reference clock frequencies and is a member of the HiPerClocksTM family of high performance clock solutions from ICS. Using a 25MHz 18pF parallel resonant crystal, the following frequencies can be generated based on the 2 frequency select pins (F_SEL[1:0]): 156.25MHz, 125MHz and 62.5MHz. The ICS8421004I-01 uses ICS’ 3rd generation low phase noise VCO technology and can achieve 1ps or lower typical rms phase jitter, easily meeting Ethernet jitter requirements. The ICS8421004I-01 is packaged in a small 24-pin TSSOP package. • Four HSTL outputs (VOHmax = 1.4V) ICS • Selectable crystal oscillator interface or LVCMOS/LVTTL single-ended input • Supports the following output frequencies: 156.25MHz, 125MHz, 62.5MHz • VCO range: 560MHz - 680MHz • RMS phase jitter @ 156.25MHz, using a 25MHz crystal (1.875MHz - 20MHz): 0.44ps (typical) • Power supply modes: Core/Output 3.3V/1.8V 2.5V/1.8V • -40°C to 85°C ambient operating temperature PIN ASSIGNMENT FREQUENCY SELECT FUNCTION TABLE 0 0 1 25 5 5 125 1 0 25 10 2.5 62.5 1 1 25 F_SEL1 F_SEL0 0 N Divider Value 4 Output Frequency (25MHz Ref.) M Divider Value 25 M/N Divider Value 6.25 156.25 not used not used F_SEL[1:0] nPLL_SEL Pulldown TEST_CLK Pulldown 2 1 1 25MHz XTAL_IN OSC 1 2 3 4 5 6 7 8 9 10 11 12 24 23 22 21 20 19 18 17 16 15 14 13 nQ2 Q2 VDDO Q3 nQ3 GND VDD nXTAL_SEL TEST_CLK GND XTAL_IN XTAL_OUT ICS8421004I-01 BLOCK DIAGRAM Pulldown nQ1 Q1 VDDO Q0 nQ0 MR nPLL_SEL nc VDDA F_SEL0 VDD F_SEL1 0 Phase Detector F_SEL[1:0] 0 0 ÷4 0 1 ÷5 10 11 VCO ÷10 Not Used 24-Lead TSSOP 4.40mm x 7.8mm x 0.92mm package body G Package Q0 Top View nQ0 Q1 nQ1 0 XTAL_OUT nXTAL_SEL Q2 Pulldown nQ2 M = 25 (fixed) MR Q3 nQ3 Pulldown The Preliminary Information presented herein represents a product in prototyping or pre-production. The noted characteristics are based on initial product characterization. Integrated Circuit Systems, Incorporated (ICS) reserves the right to change any circuitry or specifications without notice. 8421004AGI-01 www.icst.com/products/hiperclocks.html 1 REV. A MACH 29, 2005 PRELIMINARY Integrated Circuit Systems, Inc. ICS8421004I-01 FEMTOCLOCKS™ CRYSTAL-TOHSTL FREQUENCY SYNTHESIZER TABLE 1. PIN DESCRIPTIONS Number Name 1, 2 nQ1, Q1 Output Differential output pair. HSTL interface levels. 3, 22 VDDO Power Output supply pins. 4, 5 Q0, nQ0 Ouput 6 MR Input 7 nPLL_SEL Input 8, 18 nc Unused 9 Power 15, 19 VDDA F_SEL0, F_SEL1 VDD XTAL_OUT, XTAL_IN GND Power 16 TEST_CLK Input 17 nXTAL_SEL Input 20, 21 nQ3, Q3 Output 23, 24 Q2, nQ2 Output 10, 12 11 13, 14 Type Input Power Input Description Differential output pair. HSTL interface levels. Active HIGH Master Reset. When logic HIGH, the internal dividers are reset causing the true outputs Qx to go low and the inver ted outputs nQx Pulldown to go high. When logic LOW, the internal dividers and the outputs are enabled. LVCMOS/LVTTL interface levels. Selects between the PLL and TEST_CLK as input to the dividers. When Pulldown LOW, selects PLL (PLL Enable). When HIGH, deselects the reference clock (PLL Bypass). LVCMOS/LVTTL interface levels. No connect. Analog supply pin. Pulldown Frequency select pins. LVCMOS/LVTTL interface levels. Core supply pin. Parallel resonant cr ystal interface. XTAL_OUT is the output, XTAL_IN is the input. Power supply ground. Pulldown LVCMOS/LVTTL clock input. Selects between cr ystal or TEST_CLK inputs as the the PLL Reference Pulldown source. Selects XTAL inputs when LOW. Selects TEST_CLK when HIGH. LVCMOS/LVTTL interface levels. Differential output pair. HSTL interface levels. Differential output pair. HSTL interface levels. NOTE: Pulldown refers to internal input resistors. See Table 2, Pin Characteristics, for typical values. TABLE 2. PIN CHARACTERISTICS Symbol Parameter Test Conditions Minimum Typical Maximum Units CIN Input Capacitance 4 pF RPULLDOWN Input Pulldown Resistor 51 kΩ 8421004AGI-01 www.icst.com/products/hiperclocks.html 2 REV. A MACH 29, 2005 PRELIMINARY Integrated Circuit Systems, Inc. ICS8421004I-01 FEMTOCLOCKS™ CRYSTAL-TOHSTL FREQUENCY SYNTHESIZER ABSOLUTE MAXIMUM RATINGS Supply Voltage, VDD 4.6V Inputs, VI -0.5V to VDD + 0.5V Outputs, IO Continuous Current Surge Current 50mA 100mA Package Thermal Impedance, θJA 70°C/W (0 mps) Storage Temperature, TSTG -65°C to 150°C NOTE: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These ratings are stress specifications only. Functional operation of product at these conditions or any conditions beyond those listed in the DC Characteristics or AC Characteristics is not implied. Exposure to absolute maximum rating conditions for extended periods may affect product reliability. TABLE 3A. POWER SUPPLY DC CHARACTERISTICS, VDD = VDDA = 3.3V±5%, VDDO = 1.8V±0.2V, TA = -40°C TO 85°C Symbol Parameter VDD Core Supply Voltage Test Conditions Minimum Typical Maximum Units 3.135 3.3 3.465 V VDDA Analog Supply Voltage 3.135 3.3 3.465 V VDDO Output Supply Voltage 3.135 3.3 3.465 V IDD Power Supply Current IDDA Analog Supply Current IDDO Output Supply Current No Load 90 mA 10 mA 0 mA TABLE 3B. POWER SUPPLY DC CHARACTERISTICS, VDD = VDDA = 2.5V±5%, VDDO = 1.8V±0.2V, TA = -40°C TO 85°C Symbol Parameter Minimum Typical Maximum Units VDD Core Supply Voltage Test Conditions 2.375 2.5 2.625 V VDDA Analog Supply Voltage 2.375 2.5 2.625 V VDDO Output Supply Voltage 2.375 2.5 2.625 IDD Power Supply Current IDDA Analog Supply Current IDDO Output Supply Current No Load V 80 mA 10 mA 0 mA TABLE 3C. LVCMOS / LVTTL DC CHARACTERISTICS, VDD = VDDA = 3.3V±5% OR 2.5V±5%, VDDO = 1.8V±0.2V, TA = -40°C TO 85°C Symbol Parameter VIH Input High Voltage VIL Input Low Voltage IIH Input High Current IIL Input Low Current 8421004AGI-01 Test Conditions VDD = 3.3V TEST_CLK, MR, F_SEL0, F_SEL1, nPLL_SEL, nXTAL_SEL TEST_CLK, MR, F_SEL0, F_SEL1, nPLL_SEL, nXTAL_SEL Minimum Typical 2 Maximum VDD + 0.3 Units V VDD = 2.5V 1. 7 VDD + 0.3 V VDD = 3.3V -0.3 0.8 V VDD = 2.5V -0.3 0.7 V 150 µA VDD = VIN = 3.465V or 2.5V VDD = 3.465V or 2.5V, VIN = 0V www.icst.com/products/hiperclocks.html 3 -150 µA REV. A MACH 29, 2005 PRELIMINARY Integrated Circuit Systems, Inc. ICS8421004I-01 FEMTOCLOCKS™ CRYSTAL-TOHSTL FREQUENCY SYNTHESIZER TABLE 3D. HSTL DC CHARACTERISTICS, VDD = VDDA = 3.3V±5%,VDDO = 1.8V±0.2V, TA = -40°C TO 85°C Symbol Parameter VOH Output High Voltage; NOTE 1 Test Conditions Minimum Maximum Units 1.0 Typical 1.4 V VOL Output Low Voltage; NOTE 1 0 0.4 V VOX Output Crossover Voltage; NOTE 2 40 60 % 0.6 1.1 V Maximum Units 1.4 V 60 % Peak-to-Peak Output Voltage Swing VSWING NOTE 1: Outputs terminated with 50Ω to ground. NOTE 2: Defined with respect to output voltage swing at a given condition. TABLE 3E. HSTL DC CHARACTERISTICS, VDD = VDDA = 2.5V±5%, VDDO =1.8V±0.2V, TA = -40°C TO 85°C Symbol Parameter VOH Output High Voltage; NOTE 1 Test Conditions Minimum Typical 1.0 VOL Output Low Voltage; NOTE 1 VOX Output Crossover Voltage; NOTE 2 0.235 40 Peak-to-Peak Output Voltage Swing VSWING NOTE 1: Outputs terminated with 50Ω to ground. NOTE 2: Defined with respect to output voltage swing at a given condition. V 0.9 V TABLE 4. CRYSTAL CHARACTERISTICS Parameter Test Conditions Minimum Mode of Oscillation Typical Maximum Units Fundamental 27.2 MHz Equivalent Series Resistance (ESR) Frequency 22.4 25 50 Ω Shunt Capacitance 7 pF Drive Level 1 mW NOTE: Characterized using an 18pF parallel resonant crystal. 8421004AGI-01 www.icst.com/products/hiperclocks.html 4 REV. A MACH 29, 2005 PRELIMINARY Integrated Circuit Systems, Inc. ICS8421004I-01 FEMTOCLOCKS™ CRYSTAL-TOHSTL FREQUENCY SYNTHESIZER TABLE 5A. AC CHARACTERISTICS, DD = VDDA = 3.3V±5%,VDDO = 1.8V±0.2V, TA = -40°C TO 85°C Symbol fOUT tsk(o) tjit(Ø) tR / tF Parameter Output Frequency Test Conditions Minimum Maximum Units F_SEL[1:0] = 00 140 Typical 170 MHz F_SEL[1:0] = 01 112 136 MHz F_SEL[1:0] = 10 56 68 MH z Output Skew; NOTE 1, 3 RMS Phase Jitter (Random); NOTE 2 Output Rise/Fall Time TBD ps 156.25MHz, (1.875MHz - 20MHz) 0.44 ps 125MHz, (1.875MHz - 20MHz) 0.48 ps 62.5MHz,(1.875MHz - 20MHz) 0.49 ps 20% to 80% 450 ps odc Output Duty Cycle 50 NOTE 1: Defined as skew between outputs at the same supply voltages and with equal load conditions. Measured at VDDO/2. NOTE 2: Please refer to the Phase Noise Plot. NOTE 3: This parameter is defined in accordance with JEDEC Standard 65. % TABLE 5B. AC CHARACTERISTICS, VDD = VDDA = 2.5V±5%, VDDO = 1.8V±0.2V, TA = -40°C TO 85°C Symbol fOUT Parameter Output Frequency tsk(o) Output Skew; NOTE 1, 3 tjit(Ø) RMS Phase Jitter (Random); NOTE 2 Test Conditions Minimum Maximum Units F_SEL[1:0] = 00 140 170 MHz F_SEL[1:0] = 01 112 136 MHz F_SEL[1:0] = 10 56 68 MH z 156.25MHz, (1.875MHz - 20MHz) tR / tF Output Rise/Fall Time Typical TBD ps 0.41 ps 125MHz, (1.875MHz - 20MHz) 0.49 ps 62.5MHz,(1.875MHz - 20MHz) 0.50 ps 20% to 80% 420 ps odc Output Duty Cycle 50 NOTE 1: Defined as skew between outputs at the same supply voltages and with equal load conditions. Measured at VDDO/2. NOTE 2 Please refer to the Phase Noise Plot. NOTE 3 This parameter is defined in accordance with JEDEC Standard 65. 8421004AGI-01 www.icst.com/products/hiperclocks.html 5 % REV. A MACH 29, 2005 PRELIMINARY Integrated Circuit Systems, Inc. ICS8421004I-01 FEMTOCLOCKS™ CRYSTAL-TOHSTL FREQUENCY SYNTHESIZER TYPICAL PHASE NOISE AT 156.25MHZ ➤ 0 -10 -20 Ethernet Jitter Filter -30 -40 156.25MHz -50 RMS Phase Jitter (Random) 1.875Mhz to 20MHz = 0.44ps (typical) -70 -80 -90 Raw Phase Noise Data -100 -110 ➤ NOISE POWER dBc Hz -60 -120 -130 -140 -150 ➤ -160 -170 -180 Phase Noise Result by adding Ethernet Filter to raw data -190 100 1k 10k 100k 1M 10M 100M OFFSET FREQUENCY (HZ) 8421004AGI-01 www.icst.com/products/hiperclocks.html 6 REV. A MACH 29, 2005 PRELIMINARY Integrated Circuit Systems, Inc. ICS8421004I-01 FEMTOCLOCKS™ CRYSTAL-TOHSTL FREQUENCY SYNTHESIZER PARAMETER MEASUREMENT INFORMATION 2.5V ± 5% 1.8V±0.2V 3.3V±5% 1.8V±0.2V VDD, VDDA, VDDO Qx SCOPE VDD, VDDA, VDDO Qx SCOPE HSTL HSTL GND GND nQx nQx 0V 0V HSTL 3.3V OUTPUT LOAD AC TEST CIRCUIT HSTL 2.5V OUTPUT LOAD AC TEST CIRCUIT nQx 80% 80% Qx VSW I N G Clock Outputs nQy 20% 20% Qy tF tR t sk(o) OUTPUT SKEW OUTPUT RISE/FALL TIME Phase Noise Plot nQ0:nQ3 Noise Power Q0:Q3 Pulse Width t Phase Noise Mask odc = f1 Offset Frequency PERIOD t PW t PERIOD f2 RMS Jitter = Area Under the Masked Phase Noise Plot RMS PHASE JITTER 8421004AGI-01 OUTPUT DUTY CYCLE/PULSE WIDTH/PERIOD www.icst.com/products/hiperclocks.html 7 REV. A MACH 29, 2005 PRELIMINARY Integrated Circuit Systems, Inc. ICS8421004I-01 FEMTOCLOCKS™ CRYSTAL-TOHSTL FREQUENCY SYNTHESIZER APPLICATION INFORMATION POWER SUPPLY FILTERING TECHNIQUES As in any high speed analog circuitry, the power supply pins are vulnerable to random noise. The ICS8421004I-01 provides separate power supplies to isolate any high switching noise from the outputs to the internal PLL. VDD, VDDA, and VDDO should be individually connected to the power supply plane through vias, and bypass capacitors should be used for each pin. To achieve optimum jitter performance, power supply isolation is required. Figure 1 illustrates how a 10Ω resistor along with a 10µF and a .01μF bypass capacitor should be connected to each VDDA. 3.3V or 2.5V VDD .01μF 10Ω VDDA .01μF 10μF FIGURE 1. POWER SUPPLY FILTERING CRYSTAL INPUT INTERFACE 2 below were determined using a 25MHz 18pF parallel resonant crystal and were chosen to minimize the ppm error. The ICS8421004I-01 has been characterized with 18pF parallel resonant crystals. The capacitor values shown in Figure XTAL_OUT C1 22p X1 18pF Parallel Crystal XTAL_IN C2 22p ICS8421004I-01 Figure 2. CRYSTAL INPUt INTERFACE 8421004AGI-01 www.icst.com/products/hiperclocks.html 8 REV. A MACH 29, 2005 PRELIMINARY Integrated Circuit Systems, Inc. ICS8421004I-01 FEMTOCLOCKS™ CRYSTAL-TOHSTL FREQUENCY SYNTHESIZER POWER CONSIDERATIONS This section provides information on power dissipation and junction temperature for the ICS821004I-01. Equations and example calculations are also provided. 1. Power Dissipation. The total power dissipation for the ICS8421004I-01 is the sum of the core power plus the power dissipated in the load(s). The following is the power dissipation for VDD = 3.3V + 5% = 3.465V, which gives worst case results. NOTE: Please refer to Section 3 for details on calculating power dissipated in the load. • • Power (core)MAX = VDD_MAX * IDD_MAX = 3.465V * 100mA = 346.5mW Power (outputs)MAX = 32.8mW/Loaded Output pair If all outputs are loaded, the total power is 4 x 32.8mW = 131.2mW Total Power_MAX (3.465V, with all outputs switching) = 346.5mW + 131.2mW = 477.7mW 2. Junction Temperature. Junction temperature, Tj, is the temperature at the junction of the bond wire and bond pad and directly affects the reliability of the device. The maximum recommended junction temperature for HiPerClockSTM devices is 125°C. The equation for Tj is as follows: Tj = θJA * Pd_total + TA Tj = Junction Temperature θJA = Junction-to-Ambient Thermal Resistance Pd_total = Total Device Power Dissipation (example calculation is in section 1 above) TA = Ambient Temperature In order to calculate junction temperature, the appropriate junction-to-ambient thermal resistance θJA must be used. Assuming a moderate air flow of 1 linear meter per second and a multi-layer board, the appropriate value is 65°C/W per Table 6 below. Therefore, Tj for an ambient temperature of 85°C with all outputs switching is: 85°C + 0.478W * 65°C/W = 99.85°C. This is well below the limit of 125°C. This calculation is only an example. Tj will obviously vary depending on the number of loaded outputs, supply voltage, air flow, and the type of board (single layer or multi-layer). TABLE 6. THERMAL RESISTANCE θJA FOR 24-PIN TSSOP, FORCED CONVECTION θJA by Velocity (Meters per Second) Multi-Layer PCB, JEDEC Standard Test Boards 8421004AGI-01 0 1 2.5 70°C/W 65°C/W 62°C/W www.icst.com/products/hiperclocks.html 9 REV. A MACH 29, 2005 PRELIMINARY Integrated Circuit Systems, Inc. ICS8421004I-01 FEMTOCLOCKS™ CRYSTAL-TOHSTL FREQUENCY SYNTHESIZER 3. Calculations and Equations. The purpose of this section is to derive the power dissipated into the load. HSTL output driver circuit and termination are shown in Figure 3. VDDO Q1 VOUT RL 50Ω FIGURE 3. HSTL DRIVER CIRCUIT AND TERMINATION To calculate worst case power dissipation into the load, use the following equations which assume a 50Ω load. Pd_H is power dissipation when the output drives high. Pd_L is the power dissipation when the output drives low. Pd_H = (V /R ) * (V OH_MIN Pd_L = (V OL_MAX L -V DD_MAX /R ) * (V L DD_MAX ) OH_MIN -V ) OL_MAX Pd_H = (1V/50Ω) * (2V - 1V) = 20mW Pd_L = (0.4V/50Ω) * (2V - 0.4V) = 12.8mW Total Power Dissipation per output pair = Pd_H + Pd_L = 32.8mW 8421004AGI-01 www.icst.com/products/hiperclocks.html 10 REV. A MACH 29, 2005 PRELIMINARY Integrated Circuit Systems, Inc. ICS8421004I-01 FEMTOCLOCKS™ CRYSTAL-TOHSTL FREQUENCY SYNTHESIZER RELIABILITY INFORMATION TABLE 7. θJAVS. AIR FLOW TABLE FOR 24 LEAD TSSOP θJA by Velocity (Meters per Second) Multi-Layer PCB, JEDEC Standard Test Boards 0 1 2.5 70°C/W 65°C/W 62°C/W TRANSISTOR COUNT The transistor count for ICS8421004I-01 is: 2951 8421004AGI-01 www.icst.com/products/hiperclocks.html 11 REV. A MACH 29, 2005 PRELIMINARY Integrated Circuit Systems, Inc. PACKAGE OUTLINE - G SUFFIX FOR ICS8421004I-01 FEMTOCLOCKS™ CRYSTAL-TOHSTL FREQUENCY SYNTHESIZER 24 LEAD TSSOP TABLE 8 PACKAGE DIMENSIONS SYMBOL Millimeters Minimum N A Maximum 24 -- 1.20 A1 0.05 0.15 A2 0.80 1.05 b 0.19 0.30 c 0.09 0.20 D 7.70 7.90 E E1 6.40 BASIC 4.30 e 4.50 0.65 BASIC L 0.45 0.75 α 0° 8° aaa -- 0.10 Reference Document: JEDEC Publication 95, MO-153 8421004AGI-01 www.icst.com/products/hiperclocks.html 12 REV. A MACH 29, 2005 PRELIMINARY Integrated Circuit Systems, Inc. ICS8421004I-01 FEMTOCLOCKS™ CRYSTAL-TOHSTL FREQUENCY SYNTHESIZER TABLE 9. ORDERING INFORMATION Part/Order Number Marking Package Count Temperature ICS8421004AGI-01 ICS421004AI01 24 Lead TSSOP 60 per tube -40°C to 85°C ICS8421004AGI-01T ICS421004AI01 24 Lead TSSOP on Tape and Reel 2500 -40°C to 85°C The aforementioned trademark, HiPerClockS™ and FEMTOCLOCKS™ is a trademark of Integrated Circuit Systems, Inc. or its subsidiaries in the United States and/or other countries. While the information presented herein has been checked for both accuracy and reliability, Integrated Circuit Systems, Incorporated (ICS) assumes no responsibility for either its use or for infringement of any patents or other rights of third parties, which would result from its use. No other circuits, patents, or licenses are implied. This product is intended for use in normal commercial and industrial applications. Any other applications such as those requiring high reliability or other extraordinary environmental requirements are not recommended without additional processing by ICS. ICS reserves the right to change any circuitry or specifications without notice. ICS does not authorize or warrant any ICS product for use in life support devices or critical medical instruments. 8421004AGI-01 www.icst.com/products/hiperclocks.html 13 REV. A MACH 29, 2005