ICS8701 Integrated Circuit Systems, Inc. LOW SKEW ÷1, ÷2 CLOCK GENERATOR GENERAL DESCRIPTION FEATURES The ICS8701 is a low skew, ÷1, ÷2 Clock Generator and a member of the HiPerClockS™ HiPerClockS™ family of High Performance Clock Solutions from ICS. The low impedance LVCMOS outputs are designed to drive 50Ω series or parallel terminated transmission lines. The effective fanout can be increased from 20 to 40 by utilizing the ability of the outputs to drive two series terminated lines. • 20 LVCMOS outputs, 7Ω typical output impedance ,&6 • 1 LVCMOS clock input • Maximum output frequency up to 250MHz • Bank enable logic allows unused banks to be disabled in reduced fanout applications • Output skew: 250ps (maximum) The divide select inputs, DIV_SELx, control the output frequency of each bank. The outputs can be utilized in the ÷1, ÷2 or a combination of ÷1 and ÷2 modes. The bank enable inputs, BANK_EN0:1, support enabling and disabling each bank of outputs individually. The master reset input, nMR/ OE, resets the internal frequency dividers and also controls the active and high impedance states of all outputs. • Part-to-part skew: 600ps (maximum) The ICS8701 is characterized at 3.3V and mixed 3.3V input supply, and 2.5V output supply operating modes. Guaranteed bank, output and part-to-part skew characteristics make the ICS8701 ideal for those clock distribution applications demanding well defined performance and repeatability. • 0°C to 70°C ambient operating temperature BLOCK DIAGRAM PIN ASSIGNMENT ÷1 1 ÷2 0 • Multiple frequency skew: 300ps (maximum) • 3.3V or mixed 3.3V input, 2.5V output operating supply modes • Other divide values available on request GND QB2 GND QB3 VDDO QB4 QC0 VDDO QC1 GND QC2 GND CLK • Bank skew: 200ps (maximum) QAO - QA4 QC3 VDDO QC4 QD0 VDDO QD1 GND QD2 GND QD3 VDDO QD4 DIV_SELA 1 QB0 - QB4 0 DIV_SELB 1 QC0 - QC4 0 DIV_SELC 1 QD0 - QD4 48 47 46 45 44 43 42 41 40 39 38 37 1 36 2 35 3 34 4 33 5 32 6 31 7 30 8 29 9 28 10 27 11 26 12 25 13 14 15 16 17 18 19 20 21 22 23 24 ICS8701 QB1 VDDO QB0 QA4 VDDO QA3 GND QA2 GND QA1 VDDO QA0 0 DIV_SELA DIV_SELB CLK GND VDD BANK_EN0 GND BANK_EN1 VDD nMR/OE DIV_SELC DIV_SELD DIV_SELD nMR/OE BANK_EN0 BANK_EN1 Bank Enable Logic 48-Pin LQFP 7mm x 7mm x 1.4mm Y Package Top View 8701CY www.icst.com/products/hiperclocks.html 1 REV. B AUGUST 2, 2001 ICS8701 Integrated Circuit Systems, Inc. LOW SKEW ÷1, ÷2 CLOCK GENERATOR TABLE 1. PIN DESCRIPTIONS Number 2, 5, 11, 26, 32, 35, 41, 44 7, 9, 18, 21, 28, 30, 37, 39, 46, 48 16, 20 25, 27, 29, 31, 33 34, 36, 38, 40, 42 43, 45, 47, 1, 3 4, 6, 8, 10, 12 22 13 DIV_SELD Input 14 DIV_SELC Input 23 DIV_SELB Input 24 DIV_SELA Input 17, 19 BANK_EN1, BANK_EN0 Input Pullup Enables and disables outputs by banks. LVCMOS interface levels. 15 nMR/OE Input Pullup Master reset and output enable. Enables and disables all outputs. LVCMOS interface levels. 8701CY Name Type Description VDDO Power Output supply pins. Connect to 3.3V or 2.5V. GND Power Power supply ground. Connect to ground. VDD QA0, QA1, QA2, QA3, QA4 QB0, QB1, QB2, QB3, QB4 QC0, QC1, QC2, QC3, QC4 QD0, QD1, QD2, QD3, QD4 CLK Power Positive supply pins. Connect to 3.3V. Output Bank A outputs. LVCMOS interface levels. 7W typical output impedance. Output Bank B outputs. LVCMOS interface levels. 7W typical output impedance. Output Bank C outputs. LVCMOS interface levels. 7W typical output impedance. Output Bank D outputs. LVCMOS interface levels 7W typical output impedance. Input Pulldown LVCMOS / LVTTL clock input. Controls frequency division for bank D outputs. Pullup LVCMOS interface levels. Controls frequency division for bank C outputs. Pullup LVCMOS interface levels. Controls frequency division for bank B outputs. Pullup LVCMOS interface levels. Controls frequency division for bank A outputs. Pullup LVCMOS interface levels. www.icst.com/products/hiperclocks.html 2 REV. B AUGUST 2, 2001 ICS8701 Integrated Circuit Systems, Inc. LOW SKEW ÷1, ÷2 CLOCK GENERATOR TABLE 2. PIN CHARACTERISTICS Symbol Parameter Test Conditions Minimum Typical RPULLUP CLK DIV_SELA, DIV_SELB, Input Capacitance DIV_SELC, DIV_SELD, BANK_EN0, NMR/OE, BANK_EN1, Input Pullup Resistor 51 RPULLDOWN Input Pulldown Resistor 51 CPD Power Dissipation Capacitance (per output) CIN Units 4 pF 4 KW KW VDD, VDDO = 3.465V pF VDD = 3.465V, VDDO = 2.625V pF Output Impedance ROUT Maximum W 7 TABLE 3. FUNCTION TABLE Inputs Outputs nMR/OE BANK_EN1 BANK_EN0 DIV_SELx QA0 - QA4 QB0 - QB4 QC0 - QC4 QD0 - QD4 0 1 1 1 1 1 1 1 1 X 0 1 0 1 0 1 0 1 X 0 0 1 1 0 0 1 1 X 0 0 0 0 1 1 1 1 Hi Z Active Active Active Active Active Active Active Active Hi Z Hi Z Active Active Active Hi Z Active Active Active Hi Z Hi Z Hi Z Active Active Hi Z Hi Z Active Active Hi Z Hi Z Hi Z Hi Z Active Hi Z Hi Z Hi Z Active 8701CY www.icst.com/products/hiperclocks.html 3 Qx frequency zero fIN/2 fIN/2 fIN/2 fIN/2 fIN fIN fIN fIN REV. B AUGUST 2, 2001 ICS8701 Integrated Circuit Systems, Inc. LOW SKEW ÷1, ÷2 CLOCK GENERATOR ABSOLUTE MAXIMUM RATINGS Supply Voltage, VDDx 4.6V Inputs, VI Outputs, VO Package Thermal Impedance, θJA Storage Temperature, TSTG -0.5V to VDD + 0.5V -0.5V to VDDO + 0.5V 47.9°C/W (0lfpm) -65°C to 150°C 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 4A. POWER SUPPLY DC CHARACTERISTICS, VDD = VDDO = 3.3V±5%, TA =0°C TO 70°C Symbol VDD VDDO Parameter Positive Supply Voltage Output Supply Voltage Test Conditions IDD Quiescent Power Supply Current Minimum 3.135 3.135 Typical 3.3 3.3 Maximum 3.465 3.465 Units V V 95 mA Maximum Units 2 3.8 V 2 3.8 V VDD = 3.465V -0.3 0.8 V VDD = 3.465V -0.3 1.3 V VDD = VIN = 3.465V 5 µA VDD = VIN = 3.465V 150 µA VDD = VIH = 3.465V VIL = 0V TABLE 4B. LVCMOS DC CHARACTERISTICS, VDD = VDDO = 3.3V±5%, TA =0°C TO 70°C Symbol VIH VIL IIH IIL Parameter Input High Voltage Input Low Voltage Input High Current Input Low Current Test Conditions DIV_SELA, DIV_SELB, DIV_SELC, DIV_SELD, BANK_EN0, BANK_EN1, nMR/OE CLK DIV_SELA, DIV_SELB, DIV_SELC, DIV_SELD, BANK_EN0, BANK_EN1, nMR/OE CLK DIV_SELA, DIV_SELB, DIV_SELC, DIV_SELD, BANK_EN0, BANK_EN1, nMR/OE CLK DIV_SELA, DIV_SELB, DIV_SELC, DIV_SELD, BANK_EN0, BANK_EN1, nMR/OE CLK Typical VDD = 3.465V, VIN = 0V -150 µA VDD = 3.465V, VIN = 0V -5 µA 2.6 V VOH Output High Voltage VDD = VDDO = 3.135V IOH = -36mA VOL Output Low Voltage VDD = VDDO = 3.135V IOL = 36mA 8701CY Minimum www.icst.com/products/hiperclocks.html 4 0.5 V REV. B AUGUST 2, 2001 ICS8701 Integrated Circuit Systems, Inc. LOW SKEW ÷1, ÷2 CLOCK GENERATOR TABLE 5A. AC CHARACTERISTICS, VDD = VDDO = 3.3V±5%, TA =0°C TO 70°C Symbol Parameter fMAX Maximum Input Frequency tPD Propagation Delay; NOTE 1 tsk(b) Bank Skew; NOTE 2, 7 tsk(o) tsk(pp) Output Skew; NOTE 3, 7 Multiple Frequency Skew; NOTE 4, 7 Par t-to-Par t Skew; NOTE 5, 7 tR Output Rise Time; NOTE 6 30% to 70% 280 tF Output Fall Time; NOTE 6 30% to 70% odc Output Duty Cycle 280 tCYCLE/2 - 0.5 2 tsk(w) Test Conditions Minimum Maximum Units 250 MHz 3.4 ns Measured on rising edge atVDDO/2 200 ps Measured on rising edge atVDDO/2 250 ps Measured on rising edge atVDDO/2 300 ps 600 ps 850 ps 850 tCYCLE/2 + 0.5 3 ps 0MHZ £ f £ 200MHz Typical 2.2 Measured on rising edge atVDDO/2 0MHZ £ f £ 200MHz f = 200MHz tCYCLE/2 2.5 ns ns Output Enable Time; f = 10MHz 6 ns NOTE 6 Output Disable Time; f = 10MHz 6 ns tDIS NOTE 6 All parameters measured at 200MHz unless noted otherwise. NOTE 1: Measured from the 50% point of the input to the output crossing point. NOTE 2: Defined as skew within a bank of outputs at the same supply voltages and with equal load conditions. NOTE 3: Defined as skew across banks of outputs at the same supply voltages and with equal load conditions. NOTE 4: Defined as skew across banks of outputs operating at different frequency with the same supply voltages and equal load conditions. NOTE 5: Defined as the skew at between outputs on different devices operating at the same supply voltages and with equal load conditions. Using the same type of inputs on each device, the outputs are measured at the cross points. NOTE 6: These parameters are guaranteed by characterization. Not tested in production. NOTE 7: This parameter is defined in accordance with JEDEC Standard 65. tEN 8701CY www.icst.com/products/hiperclocks.html 5 REV. B AUGUST 2, 2001 ICS8701 Integrated Circuit Systems, Inc. LOW SKEW ÷1, ÷2 CLOCK GENERATOR TABLE 4C. POWER SUPPLY DC CHARACTERISTICS, VDD = 3.3V±5%, VDDO = 2.5V±5%, TA = 0°C TO 70°C Symbol VDD VDDO Parameter Positive Supply Voltage Output Supply Voltage Test Conditions IDD Quiescent Power Supply Current Minimum 3.135 2.375 Typical 3.3 2.5 Maximum 3.465 2.625 Units V V 95 mA Maximum Units 2 3.8 V 2 3.8 V VDD = 3.465V -0.3 0.8 V VDD = 3.465V -0.3 1.3 V VDD = VIN = 3.465V 5 µA VDD = VIN = 3.465V 150 µA VDD = VIH = 3.465V VIL = 0V TABLE 4D. LVCMOS DC CHARACTERISTICS, VDD = 3.3V±5%, VDDO = 2.5V±5%, TA = 0°C TO 70°C Symbol VIH VIL IIH IIL Parameter Input High Voltage Input Low Voltage Input High Current Input Low Current Test Conditions DIV_SELA, DIV_SELB, DIV_SELC, DIV_SELD, BANK_EN0, BANK_EN1, nMR/OE CLK DIV_SELA, DIV_SELB, DIV_SELC, DIV_SELD, BANK_EN0, BANK_EN1, nMR/OE CLK DIV_SELA, DIV_SELB, DIV_SELC, DIV_SELD, BANK_EN0, BANK_EN1, nMR/OE CLK DIV_SELA, DIV_SELB, DIV_SELC, DIV_SELD, BANK_EN0, BANK_EN1, nMR/OE CLK VOH Output High Voltage VOL Output Low Voltage Minimum Typical VDD = 3.465V, VIN = 0V -150 µA VDD = 3.465V, VIN = 0V VDD = 3.135V, VDDO = 2.375 IOH = -27mA VDD = 3.135V, VDDO = 2.375 -5 µA 1.8 V 0.5 V IOL = 27mA 8701CY www.icst.com/products/hiperclocks.html 6 REV. B AUGUST 2, 2001 ICS8701 Integrated Circuit Systems, Inc. LOW SKEW ÷1, ÷2 CLOCK GENERATOR TABLE 5B. AC CHARACTERISTICS, VDD = 3.3V±5%, VDDO = 2.5V±5%, TA = 0°C TO 70°C Symbol Parameter fMAX Maximum Input Frequency Test Conditions Minimum 0MHZ £ f £ 200MHz Typical Units 250 MHz tPD Propagation Delay; NOTE 1 3.6 ns tsk(b) Bank Skew; NOTE 2, 7 Measured on rising edge atVDDO/2 225 ps tsk(o) Measured on rising edge atVDDO/2 250 ps Measured on rising edge atVDDO/2 300 ps tsk(pp) Output Skew; NOTE 3, 7 Multiple Frequency Skew; NOTE 4, 7 Par t-to-Par t Skew; NOTE 5, 7 Measured on rising edge atVDDO/2 600 ps tR Output Rise Time; NOTE 6 30% to 70% 280 850 ps tF Output Fall Time; NOTE 6 30% to 70% Output Duty Cycle 850 tCYCLE/2 + 0.5 3 ps odc 280 tCYCLE/2 - 0.5 2 tsk(w) 0MHZ £ f £ 200MHz 2.6 Maximum tCYCLE/2 ns f = 200MHz 2.5 ns Output Enable Time; f = 10MHz 6 ns tEN NOTE 6 Output Disable Time; f = 10MHz 6 ns tDIS NOTE 6 All parameters measured at 200MHz unless noted otherwise. NOTE 1: Measured from the 50% point of the input to the output crossing point. NOTE 2: Defined as skew within a bank of outputs at the same supply voltages and with equal load conditions. NOTE 3: Defined as skew across banks of outputs at the same supply voltages and with equal load conditions. NOTE 4: Defined as skew across banks of outputs operating at different frequency with the same supply voltages and equal load conditions. NOTE 5: Defined as the skew at between outputs on different devices operating at the same supply voltages and with equal load conditions. Using the same type of inputs on each device, the outputs are measured at the cross points. NOTE 6: These parameters are guaranteed by characterization. Not tested in production. NOTE 7: This parameter is defined in accordance with JEDEC Standard 65. 8701CY www.icst.com/products/hiperclocks.html 7 REV. B AUGUST 2, 2001 ICS8701 Integrated Circuit Systems, Inc. LOW SKEW ÷1, ÷2 CLOCK GENERATOR PARAMETER MEASUREMENT INFORMATION VDD VDDO SCOPE LVCMOS Qx VDD = +1.65V VDDO = 1.65V GND = -1.65V FIGURE 1A - 3.3V OUTPUT LOAD TEST CIRCUIT VDDO SCOPE LVCMOS Qx VDDO = +1.25V GND = -1.25V FIGURE 1B - 2.5V OUTPUT LOAD TEST CIRCUIT 8701CY www.icst.com/products/hiperclocks.html 8 REV. B AUGUST 2, 2001 ICS8701 Integrated Circuit Systems, Inc. LOW SKEW ÷1, ÷2 CLOCK GENERATOR Qx Qy tsk(o) FIGURE 2 - OUTPUT SKEW PART 1 Qx PART 2 Qy tsk(pp) FIGURE 3 - PART-TO-PART SKEW 8701CY www.icst.com/products/hiperclocks.html 9 REV. B AUGUST 2, 2001 ICS8701 Integrated Circuit Systems, Inc. LOW SKEW ÷1, ÷2 CLOCK GENERATOR 80% 80% V 20% 20% Clock Inputs and Outputs t t R FIGURE 4 - INPUT V SWING AND OUTPUT RISE AND F FALL TIME /2 CC CLK QAx, QBx, QCx, QDx t PD FIGURE 5 - PROPAGATION DELAY CLK, QAx, QBx, QCx, QDx Pulse Width t t odc = t PERIOD PW PERIOD FIGURE 6 - odc & tPERIOD 8701CY www.icst.com/products/hiperclocks.html 10 REV. B AUGUST 2, 2001 ICS8701 Integrated Circuit Systems, Inc. LOW SKEW ÷1, ÷2 CLOCK GENERATOR POWER CONSIDERATIONS This section provides information on power dissipation and junction temperature for the ICS8701-01. Equations and example calculations are also provided. 1. Power Dissipation. The total power dissipation for the ICS8701-01 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 * 95mA = 329.2mW Power (outputs)MAX = 32mW/Loaded Output pair If all outputs are loaded, the total power is 20 * 32mW = 640mW Total Power_MAX (3.465V, with all outputs switching) = 329.2mW + 640mW = 969.2mW 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 200 linear feet per minute and a multi-layer board, the appropriate value is 42.1°C/W per Table 6 below. Therefore, Tj for an ambient temperature of 70°C with all outputs switching is: 70°C + 0.969W * 42.1°C/W = 110.8°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 48-pin LQFP, Forced Convection θJA by Velocity (Linear Feet per Minute) 0 Single-Layer PCB, JEDEC Standard Test Boards Multi-Layer PCB, JEDEC Standard Test Boards 67.8°C/W 47.9°C/W 200 55.9°C/W 42.1°C/W 500 50.1°C/W 39.4°C/W NOTE: Most modern PCB designs use multi-layered boards. The data in the second row pertains to most designs. 8701CY www.icst.com/products/hiperclocks.html 11 REV. B AUGUST 2, 2001 ICS8701 Integrated Circuit Systems, Inc. LOW SKEW ÷1, ÷2 CLOCK GENERATOR 3. Calculations and Equations. The purpose of this section is to derive the power dissipated into the load. LVCMOS output driver circuit and termination are shown in Figure 7. VDDO Q1 VOUT RL 50Ω FIGURE 7 - LVCMOS DRIVER CIRCUIT AND TERMINATION To calculate worst case power dissipation into the load, use the following equations which assume a 50Ω load, and a termination voltage of V - 2V. DD 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_MAX Pd_L = (V OL_MAX • L -V DD_MAX /R ) * (V L -V DD_MAX For logic high, V ) OL_MAX =V OUT • ) OH_MAX For logic low, V OUT =V OH_MAX =V OL_MAX – 1.2V DD_MAX =V – 0.4V DD_MAX Pd_H = (1.2V/50Ω) * (2V - 1.2V) = 19.2mW Pd_L = (0.4V/50Ω) * (2V - 0.4V) = 12.8mW Total Power Dissipation per output pair = Pd_H + Pd_L = 32mW 8701CY www.icst.com/products/hiperclocks.html 12 REV. B AUGUST 2, 2001 ICS8701 Integrated Circuit Systems, Inc. LOW SKEW ÷1, ÷2 CLOCK GENERATOR RELIABILITY INFORMATION TABLE 7. θJAVS. AIR FLOW TABLE θJA by Velocity (Linear Feet per Minute) 0 Single-Layer PCB, JEDEC Standard Test Boards Multi-Layer PCB, JEDEC Standard Test Boards 67.8°C/W 47.9°C/W 200 55.9°C/W 42.1°C/W 500 50.1°C/W 39.4°C/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 ICS8701 is: 1743 8701CY www.icst.com/products/hiperclocks.html 13 REV. B AUGUST 2, 2001 ICS8701 Integrated Circuit Systems, Inc. LOW SKEW ÷1, ÷2 CLOCK GENERATOR PACKAGE OUTLINE - Y SUFFIX TABLE 8. PACKAGE DIMENSIONS JEDEC VARIATION ALL DIMENSIONS IN MILLIMETERS SYMBOL BBC MINIMUM NOMINAL MAXIMUM 48 N A -- -- 1.60 A1 0.05 -- 0.15 A2 1.35 1.40 1.45 b 0.17 0.22 0.27 c 0.09 -- 0.20 D 9.00 BASIC D1 7.00 BASIC D2 5.50 Ref. E 9.00 BASIC E1 7.00 BASIC E2 5.50 Ref. 0.50 BASIC e L 0.45 0.60 0.75 q 0° -- 7° ccc -- -- 0.08 Reference Document: JEDEC Publication 95, MS-026 8701CY www.icst.com/products/hiperclocks.html 14 REV. B AUGUST 2, 2001 ICS8701 Integrated Circuit Systems, Inc. LOW SKEW ÷1, ÷2 CLOCK GENERATOR TABLE 9. ORDERING INFORMATION Part/Order Number Marking Package Count Temperature ICS8701CY ICS8701CY 48 Lead LQFP 250 per tray 0°C to 70°C ICS8701CYT ICS8701CY 48 Lead LQFP on Tape and Reel 1000 0°C to 70°C 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. 8701CY www.icst.com/products/hiperclocks.html 15 REV. B AUGUST 2, 2001