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Integrated Circuit Systems, Inc. ICS81006 VCXO-TO-6 LVCMOS OUTPUTS FEATURES * Six LVCMOS/LVTTL outputs, 20 nominal output impedance * Output Q5 can be selected for /1 or /2 frequency relative to the crystal frequency * Output frequency range: 12MHz to 40MHz * Crystal pull range: 90ppm (typical) * Synchronous output enable places outputs in High-Z state * On-chip filter on VIN to suppress noise modulation of VCXO * VDD/VDDO combinations 3.3V/3.3V 3.3V/2.5V 3.3V/1.8V 2.5V/2.5V 2.5V/1.8V * 4mm x 4mm 20 Lead VFQFN package is ideal for space constrained designs * 0C to 70C ambient operating temperature * Available in both standard and lead-free RoHS compliant packages GENERAL DESCRIPTION The ICS81006 is a high performance, low jitter/low phase noise VCXO and is a HiPerClockSTM member of the HiPerClockSTM family of high performance clock solutions from ICS. The ICS81006 works in conjunction with a pullable crystal to generate an output clock over the range of 12MHz - 40MHz and has 6 LVCMOS outputs, effectively integrating a fanout buffer function. IC S The frequency of the VCXO is adjusted by the VC control voltage input. The output range is 100ppm around the nominal crystal frequency. The VC control voltage range is 0 - V DD. The device is packaged in a small 4mm x 4mm VFQFN package and is ideal for use on space constrained boards typically encountered in ADSL/ VDSL applications. BLOCK DIAGRAM OE0 (Pullup) PIN ASSIGNMENT GND VDDO OE0 SYNC Q0 Q0 VC LP Filter XTAL_IN XTAL_OUT 1 2 3 4 5 20 19 18 17 16 15 14 13 12 6 OE1 Q1 GND Q2 VDDO Q3 GND Q1 XTAL_IN VDD VC VCXO Q2 XTAL_OUT Q3 DIV_SEL_Q5 7 GND 8 Q5 9 VDDO 11 10 Q4 ICS81006 Q4 20-Lead VFQFN 4mm x 4mm x 0.95 package body K Package Top View 0: /1 1: /2 DIV_SEL_Q5 (Pulldown) Q5 OE1 (Pullup) SYNC www.icst.com/products/hiperclocks.html 1 REV. A JANUARY 4, 2006 81006AK Integrated Circuit Systems, Inc. ICS81006 VCXO-TO-6 LVCMOS OUTPUTS TABLE 1. PIN DESCRIPTIONS Number 1, 2 3 4 Name XTAL_IN, XTAL_OUT VDD VC Type Input Power Input Description Crystal oscillator interface. XTAL_IN is the input. XTAL_OUT is the output. Core supply pin. Control voltage input. Output divider select pin for Q5 output. When LOW, /1. When HIGH, 5 DIV_SEL_Q5 Input Pulldown /2, LVCMOS/LVTTL interface levels. Output enable pin. When HIGH, Q5 output is enabled. 6 OE1 Input Pullup When LOW, forces Q5 to HiZ state. LVCMOS/LVTTL interface levels. 7, 11, 15, 19 GND Power Power supply ground. 8, 10, 12, Q5, Q4, Q3, Single-ended clock outputs. LVCMOS/LVTTL interface levels. Output 14, 16, 18 Q2, Q1, Q0 15 typical output impedance. 9, 13, 17 VDDO Power Output supply pins. Output enable pin. When HIGH, Q0:Q4 outputs are enabled. When 20 OE0 Input Pullup LOW, forces Q0:Q4 to HiZ state. LVCMOS/LVTTL interface levels. NOTE: Pullup and Pulldown refers to internal input resistors. See Table 2, Pin Characteristics, for typical values. TABLE 2. PIN CHARACTERISTICS Symbol CIN Parameter Input Capacitance OE0, OE1 VDD = VDDO = 3.465V CPD Power Dissipation Capacitance VDD = 3.465V or 2.625V, VDDO = 2.625V VDD = 3.465V or 2.625V, VDDO = 2V RPULLUP RPULLDOWN ROUT Input Pullup Resistor Input Pulldown Resistor VDDO = 3.3V Output Impedance VDDO = 2.5V VDDO = 1.8V 51 51 20 25 38 Test Conditions Minimum Typical 4 3 4 6 Maximum Units pF pF pF pF k k 81006AK www.icst.com/products/hiperclocks.html 2 REV. A JANUARY 4, 2006 Integrated Circuit Systems, Inc. ICS81006 VCXO-TO-6 LVCMOS OUTPUTS ABSOLUTE MAXIMUM RATINGS Supply Voltage, VDD Inputs, VI Outputs, VO Package Thermal Impedance, JA Storage Temperature, TSTG 4.6V -0.5V to VDD + 0.5 V -0.5V to VDD + 0.5V 38.5C/W (0 mps) -65C to 150C 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 = 3.3V5%, VDDO = 3.3V5% = 2.5V5% = 1.8V0.2V, TA = 0C TO 70C Symbol VDD VDDO IDD IDDO Parameter Core Supply Voltage Output Supply Voltage Power Supply Current Output Supply Current Test Conditions Minimum 3.135 3.135 2.375 1.6 Typical 3.3 3.3 2.5 1.8 Maximum 3.465 3.465 2.625 2.0 50 20 Units V V V V mA mA TABLE 3B. POWER SUPPLY DC CHARACTERISTICS, VDD = 2.5V5%, VDDO = 2.5V5% = 1.8V0.2V, TA = 0C TO 70C Symbol VDD VDDO IDD IDDO Parameter Core Supply Voltage Output Supply Voltage Power Supply Current Output Supply Current Test Conditions Minimum 2.375 2.375 1.6 Typical 2. 5 2. 5 1.8 Maximum 2.625 2.625 2.0 50 20 Units V V V mA mA TABLE 3C. LVCMOS/LVTTL DC CHARACTERISTICS, TA = 0C TO 85C Symbol VIH VIL VC IIH IIL II VOH Parameter Input High Voltage Input Low Voltage OE0, OE1, DIV_SEL_Q5 DIV_SEL_Q5 OE0, OE1 DIV_SEL_Q5 OE0, OE1 Test Conditions VDD = 3.3V 5% VDD = 2.5V 5% VDD = 3.3V 5% VDD = 2.5V 5% VDD = 3.3V or 2.5V 5% VDD = 3.3V or 2.5V 5% VDD = 3.3V or 2.5V 5% VDD = 3.3V or 2.5V 5% VDD = 3.465V or 2.625V VDDO = 3.3V 5% Output High Voltage;NOTE 1 VDDO = 2.5V 5% VDDO = 1.8V 0.2V VOL Output Low Voltage;NOTE 1 VDDO = 3.3V or 2.5V 5% VDDO = 1.8V 0.2V www.icst.com/products/hiperclocks.html 3 Minimum 2 1.7 -0.3 -0.3 0 Typical Maximum VDD + 0.3 VDD + 0.3 0.8 0.7 VDD 15 0 5 Units V V V V V A A A A VCXO Control Voltage Input High Current Input Low Current -5 -150 -100 2.6 1.8 1.5 0.5 0.4 100 Input Current of VC pin A V V V V V NOTE 1: Outputs terminated with 50 to VDDO/2. See Parameter Measurement section, "Load Test Circuit" diagrams. 81006AK REV. A JANUARY 4, 2006 Integrated Circuit Systems, Inc. ICS81006 VCXO-TO-6 LVCMOS OUTPUTS TABLE 4A. AC CHARACTERISTICS, VDD = VDDO = 3.3V5%, TA = 0C TO 70C Symbol fOUT t jit(O) tsk(o) tR / tF Parameter Output Frequency RMS Phase Jitter (Random); NOTE 1 Q0:Q4 Output Skew; NOTE 2, 3 Q0:Q5 Output Rise/Fall Time Test Conditions Minimum 12 Integration Range: 1kHz- 1MHz Typical 19.44 0.35 30 DIV_SEL_Q5 = /1 20% to 80% 200 100 700 56 Maximum 40 Units MHz ps ps ps ps % odc Output Duty Cycle 44 NOTE 1: Please refer to the Phase Noise Plot. NOTE 2: Defined as skew between outputs at the same supply voltage and with equal load conditions. Measured at the output differential cross points. NOTE 3: This parameter is defined in accordance with JEDEC Standard 65. TABLE 4B. AC CHARACTERISTICS, VDD = 3.3V5%, VDDO = 2.5V5%, TA = 0C TO 70C Symbol fOUT t jit(O) tsk(o) t R / tF Parameter Output Frequency RMS Phase Jitter (Random); NOTE 1 Q0:Q4 Output Skew; NOTE 2, 3 Q0:Q5 Output Rise/Fall Time Test Conditions Minimum 12 Integration Range: 1kHz- 1MHz Typical 19.44 0.38 20 DIV_SEL_Q5 = /1 20% to 80% 300 90 800 55 Maximum 40 Units MHz ps ps ps ps % odc Output Duty Cycle 45 NOTE 1: Please refer to the Phase Noise Plot. NOTE 2: Defined as skew between outputs at the same supply voltage and with equal load conditions. Measured at the output differential cross points. NOTE 3: This parameter is defined in accordance with JEDEC Standard 65. TABLE 4C. AC CHARACTERISTICS, VDD = 3.3V5%, VDDO = 1.8V0.2V, TA = 0C TO 70C Symbol fOUT t jit(O) tsk(o) t R / tF Parameter Output Frequency RMS Phase Jitter (Random); NOTE 1 Q0:Q4 Output Skew; NOTE 2, 3 Q0:Q5 Output Rise/Fall Time Test Conditions Minimum 12 Integration Range: 1kHz-1MHz Typical 19.44 0.27 46 DIV_SEL_Q5 = /1 20% to 80% 450 175 1400 56 Maximum 40 Units MHz ps ps ps ps % odc Output Duty Cycle 44 NOTE 1: Please refer to the Phase Noise Plot. NOTE 2: Defined as skew between outputs at the same supply voltage and with equal load conditions. Measured at the output differential cross points. NOTE 3: This parameter is defined in accordance with JEDEC Standard 65. 81006AK www.icst.com/products/hiperclocks.html 4 REV. A JANUARY 4, 2006 Integrated Circuit Systems, Inc. ICS81006 VCXO-TO-6 LVCMOS OUTPUTS TABLE 4D. AC CHARACTERISTICS, VDD = VDDO = 2.5V5%, TA = 0C TO 70C Symbol fOUT t jit(O) tsk(o) tR / tF Parameter Output Frequency RMS Phase Jitter (Random); NOTE 1 Q0:Q4 Output Skew; NOTE 2, 3 Q0:Q5 Output Rise/Fall Time Test Conditions Minimum 12 Integration Range: 1kHz-1MHz Typical 19.44 0.28 25 DIV_SEL_Q5 = /1 20% to 80% 300 100 800 55 Maximum 40 Units MHz ps ps ps ps % odc Output Duty Cycle 45 NOTE 1: Please refer to the Phase Noise Plot. NOTE 2: Defined as skew between outputs at the same supply voltage and with equal load conditions. Measured at the output differential cross points. NOTE 3: This parameter is defined in accordance with JEDEC Standard 65. TABLE 4E. AC CHARACTERISTICS, VDD = 2.5V5%, VDDO = 1.8V0.2V, TA = 0C TO 70C Symbol fOUT t jit(O) tsk(o) tR / tF Parameter Output Frequency RMS Phase Jitter (Random); NOTE 1 Q0:Q4 Output Skew; NOTE 2, 3 Q0:Q5 Output Rise/Fall Time Test Conditions Minimum 12 Integration Range: 1kHz-1MHz Typical 19.44 0.26 40 DIV_SEL_Q5 = /1 20% to 80% 450 175 1400 60 Maximum 40 Units MHz ps ps ps ps % odc Output Duty Cycle 40 NOTE 1: Please refer to the Phase Noise Plot. NOTE 2: Defined as skew between outputs at the same supply voltage and with equal load conditions. Measured at the output differential cross points. NOTE 3: This parameter is defined in accordance with JEDEC Standard 65. 81006AK www.icst.com/products/hiperclocks.html 5 REV. A JANUARY 4, 2006 Integrated Circuit Systems, Inc. ICS81006 VCXO-TO-6 LVCMOS OUTPUTS AT TYPICAL PHASE NOISE 0 -10 -20 -30 -40 -50 -60 -70 -80 -90 -100 -110 -120 -130 -140 -150 -160 -170 -180 -190 100 1k 19.44MHZ @ 3.3V CORE/3.3V OUTPUT 19.44MHz RMS Phase Jitter (Random) 1kHz to 1MHz = 0.35ps (typical) NOISE POWER dBc Hz 10k 100k 1M OFFSET FREQUENCY (HZ) 81006AK www.icst.com/products/hiperclocks.html 6 REV. A JANUARY 4, 2006 Integrated Circuit Systems, Inc. ICS81006 VCXO-TO-6 LVCMOS OUTPUTS PARAMETER MEASUREMENT INFORMATION 1.65V5% 2.05V5% 1.25V5% VDD, VDDO SCOPE Qx VDD VDDO SCOPE Qx LVCMOS GND LVCMOS GND -1.65V5% -1.25V5% 3.3V CORE/3.3V OUTPUT LOAD AC TEST CIRCUIT 3.3V CORE/2.5V OUTPUT LOAD AC TEST CIRCUIT 2.4V0.065V 0.9V0.1V 1.25V5% VDD VDDO SCOPE Qx VDD, VDDO SCOPE Qx LVCMOS GND LVCMOS GND -0.9V0.1V -1.25V5% 3.3V CORE/1.8V OUTPUT LOAD AC TEST CIRCUIT 1.6V0.025V 0.9V0.1V 2.5V CORE/2.5V OUTPUT LOAD AC TEST CIRCUIT Phase Noise Plot VDD VDDO SCOPE Qx Noise Power Phase Noise Mask LVCMOS GND f1 Offset Frequency f2 RMS Jitter = Area Under the Masked Phase Noise Plot -0.9V0.1V 2.5 CORE/1.8V OUTPUT LOAD AC TEST CIRCUIT 81006AK RMS PHASE JITTER REV. A JANUARY 4, 2006 www.icst.com/products/hiperclocks.html 7 Integrated Circuit Systems, Inc. ICS81006 VCXO-TO-6 LVCMOS OUTPUTS V DDO V DD Qx 2 Q0:Q5 t PW V 2 t 2 tsk(o) DDO PERIOD Qy odc = t PW t PERIOD x 100% OUTPUT SKEW OUTPUT DUTY CYCLE/PULSE WIDTH/PERIOD 80% 20% tR 80% 20% tF Clock Outputs OUTPUT RISE/FALL TIME 81006AK www.icst.com/products/hiperclocks.html 8 REV. A JANUARY 4, 2006 Integrated Circuit Systems, Inc. ICS81006 VCXO-TO-6 LVCMOS OUTPUTS APPLICATION INFORMATION VCXO CRYSTAL SELECTION Choosing a crystal with the correct characteristics is one of the most critical steps in using a Voltage Controlled Crystal Oscillator (VCXO). The crystal parameters affect the tuning range and accuracy of a VCXO. Below are the key variables and an example of using the crystal parameters to calculate the tuning range of the VCXO. VC CV Oscillator Control Voltage VCXO (Internal) XTAL C V C S1 C S2 FIGURE 1: VCXO OSCILLATOR CIRCUIT VC Control voltage used to tune frequency C V Varactor capacitance, varies due to the change in control voltage CL1, CL2 Load tuning capacitance used for fine tuning or centering nominal frequency CS1, CS2 Stray Capacitance caused by pads, vias, and other board parasitics TABLE 5. EXAMPLE CRYSTAL PARAMETERS Symbol fN fT fS CL CO C0, C1 ESR Parameter Nominal Frequency Frequency Tolerance Frequency Stability Operating Temperature Range Load Capacitance Shunt Capacitance Pullability Ratio Equivalent Series Resistance Drive Level Aging @ 25C Mode of Operation 3 per year Fundamental 0 12 4 220 240 20 1 mW ppm Test Conditions Minimum Typical 19.44 20 20 70 Maximum Units MHz ppm ppm C pF pF 81006AK www.icst.com/products/hiperclocks.html 9 Optional C L1 C L2 REV. A JANUARY 4, 2006 Integrated Circuit Systems, Inc. ICS81006 VCXO-TO-6 LVCMOS OUTPUTS TABLE 6. VARACTOR PARAMETERS Symbol CV_LOW CV_HIGH Parameter Low Varactor Capacitance High Varactor Capacitance Test Conditions VC = 0V VC = 3.3V Minimum Typical 15.4 29. 6 Maximum Units pF pF FORMULAS C Low = (C (C L1 L1 + C S 1 + CV _ Low ) + (C L 2 + C S 2 + CV _ Low ) + C S 1 + CV _ Low ) (C L 2 + C S 2 + CV _ Low ) C High = (C (C L1 + C S 1 + CV _ High ) + (C L 2 + C S 2 + CV _ High ) L1 + C S1 + CV _ High ) (C L 2 + C S 2 + CV _ High ) * CLow is the effective capacitance due to the low varactor capacitance, load capacitance and stray capacitance. CLow determines the high frequency component on the TPR. * CHigh is the effective capacitance due to the high varactor capacitance, load capacitance and stray capacitance. CHigh determines the low frequency component on the TPR. 1 1 10 6 - Total Pull Range (TPR ) = C 0 1 + C Low 2 C 0 1 + C High 2 C1 C0 C1 C0 Absolute Pull Range (APR) = Total Pull Range - (Frequency Tolerance + Frequency Stability + Aging) EXAMPLE CALCULATIONS Using the tables and figures above, we can now calculate the TPR and APR of the VCXO using the example crystal parameters. For the numerical example below there were some assumptions made. First, the stray capacitance (CS1, CS2), which is all the excess capacitance due to board parasitic, is 4pF. Second, the expected lifetime of the project is 5 years; hence the inaccuracy due to aging is 15ppm. Third, though many boards will not require load tuning capacitors (CL1, CL2), it is recommended for long-term consistent performance of the system that two tuning capacitor pads be placed into every design. Typical values for the load tuning capacitors will range from 0 to 4pF. CHigh = CLow = (0 + 4 pf + 15.4 pf ) (0 + 4 pf + 15.4 pf ) = 9.7 pf (0 + 4 pf + 15.4 pf ) + (0 + 4 pf + 15.4 pf ) (0 + 4 pf + 29.6 pf ) (0 + 4 pf + 29.6 pf ) = 16.8 pf (0 + 4 pf + 29.6 pf ) + (0 + 4 pf + 29.6 pf ) 1 1 106 = 226.5 ppm - TPR = 2 220 1 + 16.8 pF 2 220 1 + 9.7 pF 4 pF 4 pF TPR = 113.25ppm APR = 113.25ppm - (20ppm + 20ppm + 15ppm) = 58.25ppm The example above will ensure a total pull range of 113.25 ppm with an APR of 58.25ppm. Many times, board designers may select their own crystal based on their application. If the application requires a tighter APR, a crystal with better pullability (C0/C1 ratio) can be used. Also, with the equations above, one can vary the frequency tolerance, temperature stability, and aging or shunt capacitance to achieve the required pullability. 81006AK www.icst.com/products/hiperclocks.html 10 REV. A JANUARY 4, 2006 Integrated Circuit Systems, Inc. ICS81006 VCXO-TO-6 LVCMOS OUTPUTS RECOMMENDATIONS FOR UNUSED INPUT AND OUTPUT PINS OUTPUTS: INPUTS: CONTROL PINS: All control pins have internal pull-ups or pull-downs; additional resistance is not required but can be added for additional protection. A 1k resistor can be used. The VC pin can not be floated. LVCMOS OUTPUT: All unused LVCMOS output can be left floating. We recommend that there is no trace attached. SCHEMATIC EXAMPLE Figure 2 shows an example of ICS81006 application schematic. The decoupling capacitors should be located as close as possible to the power pin. For the LVCMOS 20 output drivers, series termination example is shown in the schematic. Additional termination approaches are shown in the LVCMOS Termination Application Note. Pull-up VDD example VDDO Quartz crystal should be placed as close to the device as possible. C1 SPARE R4 1K VDD 20 19 18 17 16 R1 Zo = 50 30 U1 XTAL 1 2 3 4 5 OE0 GND Q0 VDDO Q1 VC = 0V to VDD VC 81006 Pull-down example R3 1K 6 7 8 9 10 OE1 GND Q5 VDDO Q4 C2 SPARE XTAL_IN XTAL_OUT VDD VC DIV_SEL_Q5 GND Q2 VDDO Q3 GND 15 14 13 12 11 R2 Zo = 50 VDD 30 R5 1K (U1-3) VDD (U1-9) VDDO (U1-13) (U1-17) C7 10uf C6 0.1uF C5 0.1uF C4 0.1uF C3 0.1uF Unused outputs can be left floating. There should be no trace attached to unused outputs. Device characterized and specification limits set with all outputs terminated. FIGURE 2. ICS81006 SCHEMATIC EXAMPLE 81006AK www.icst.com/products/hiperclocks.html 11 REV. A JANUARY 4, 2006 Integrated Circuit Systems, Inc. ICS81006 VCXO-TO-6 LVCMOS OUTPUTS RELIABILITY INFORMATION TABLE 7. JAVS. AIR FLOW TABLE FOR 20 LEAD VFQFN JA by Velocity (Meters Per Second) 0 Single-Layer PCB, JEDEC Standard Test Boards Multi-Layer PCB, JEDEC Standard Test Boards 141.7C/W 38.5C/W 1 126.0C/W 35.0C/W 2.5 116.9C/W 33.4C/W NOTE: Most modern PCB designs use multi-layered boards. The data in the second row pertains to most designs. TRANSISTOR COUNT The transistor count for ICS81006 is: 983 81006AK www.icst.com/products/hiperclocks.html 12 REV. A JANUARY 4, 2006 Integrated Circuit Systems, Inc. ICS81006 VCXO-TO-6 LVCMOS OUTPUTS 20 LEAD VFQFN PACKAGE OUTLINE - K SUFFIX FOR TABLE 8. PACKAGE DIMENSIONS JEDEC VARIATION ALL DIMENSIONS IN MILLIMETERS SYMBOL N A A1 A3 b e ND NE D D2 E E2 L 0.75 0.35 0.75 4.0 2.80 0.75 0.18 0.50 BASIC 5 5 4.0 2.80 0.80 0 0.25 Reference 0.30 MINIMUM 20 1. 0 0.05 MAXIMUM Reference Document: JEDEC Publication 95, MO-220 81006AK www.icst.com/products/hiperclocks.html 13 REV. A JANUARY 4, 2006 Integrated Circuit Systems, Inc. ICS81006 VCXO-TO-6 LVCMOS OUTPUTS TABLE 9. ORDERING INFORMATION Part/Order Number ICS81006AK ICS81006AKT ICS81006AKLF ICS81006AKLFT Marking 81006A 81006A TBD TBD Package 20 lead VFQFN 20 lead VFQFN 20 lead "Lead-Free" VFQFN 20 lead "Lead-Free" VFQFN Shipping Packaging tube 2500 tape & reel tube 2500 tape & reel Temperature 0C to 70C 0C to 70C 0C to 70C 0C to 70C NOTE: Par ts that are ordered with an "LF" suffix to the par t number are the Pb-Free configuration and are RoHS compliant. The aforementioned trademark, HiPerClockS 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 applications. Any other applications such as those requiring extended temperature range, 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. 81006AK www.icst.com/products/hiperclocks.html 14 REV. A JANUARY 4, 2006 |
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