8741004BGILFT

PRELIMINARY DIFFERENTIAL-TO-LVDS/0.7V DIFFERENTIAL PCI EXPRESS™ JITTER ATTENUATOR ICS8741004I General Description The ICS8741004I is a high performance Differential-to-LVDS/0.7V Differential Jitter HiPerClockS™ Attenuator designed for use in PCI Express™ systems. In some PCI Express systems, such as those found in desktop PCs, the PCI Express clocks are generated from a low bandwidth, high phase noise PLL frequency synthesizer. In these systems, a jitter attenuator may be required to attenuate high frequency random and deterministic jitter components from the PLL synthesizer and from the system board. The ICS8741004I has 3 PLL bandwidth modes: 200kHz, 600kHz and 2MHz. The 200kHz mode will provide maximum jitter attenuation, but with higher PLL tracking skew and spread spectrum modulation from the motherboard synthesizer may be attenuated. The 600kHz provides an intermediate bandwidth that can easily track triangular spread profiles, while providing good jitter attenuation. The 2MHz bandwidth provides the best tracking skew and will pass most spread profiles, but the jitter attenuation will not be as good as the lower bandwidth modes. Because some 2.5Gb serdes have x20 multipliers while others have x25 multipliers, the ICS8741004I can be set for 1:1 mode or 5/4 multiplication mode (i.e. 100MHz input/125MHz output) using the F_SEL pins. Features • • • • • • • • • • • Two LVDS and two 0.7V differential output pairs Bank A has two LVDS output pairs and Bank B has two 0.7V differential output pairs One differential clock input pair CLK, nCLK pair can accept the following differential input levels: LVPECL, LVDS, LVHSTL, SSTL, HCSL Output frequency range: 98MHz - 160MHz Input frequency range: 98MHz - 128MHz VCO range: 490MHz - 640MHz Cycle-to-cycle jitter: 35ps (maximum) Full 3.3V operating supply Three bandwidth modes allow the system designer to make jitter attenuation/tracking skew design trade-offs -40°C to 85°C ambient operating temperature Available in both standard (RoHS 5) and lead-free (RoHS 6) packages ICS The ICS8741004I uses IDT’s 3rd Generation FemtoClock™ PLL technology to achieve the lowest possible phase noise. The device is packaged in a 24 Lead TSSOP package, making it ideal for use in space constrained applications such as PCI Express add-in cards. Pin Assignment nQA1 QA1 VDDO QA0 nQA0 MR BW_SEL nc VDDA F_SELA VDD OEA 1 2 3 4 5 6 7 8 9 10 11 12 24 23 22 21 20 19 18 17 16 15 14 13 nQB1 QB1 VDDO QB0 nQB0 IREF F_SELB OEB GND GND nCLK CLK PLL Bandwidth BW_SEL 0 = PLL Bandwidth: ~200kHz Float = PLL Bandwidth: ~600kHz (default) 1 = PLL Bandwidth: ~2MHz 24-Lead TSSOP, E-Pad 4.40mm x 7.8mm x 0.925mm package body G Package Top View The Preliminary Information presented herein represents a product in pre-production. The noted characteristics are based on initial product characterization and/or qualification. Integrated Device Technology, Incorporated (IDT) reserves the right to change any circuitry or specifications without notice. IDT™ / ICS™ PCI EXPRESS™ JITTER ATTENUATOR 1 ICS8741004BGI REV. B SEPTEMBER 27, 2007 ICS8741004I DIFFERENTIAL-TO-LVDS/0.7V DIFFERENTIAL PCI EXPRESS™ JITTER ATTENUATOR PRELIMINARY Block Diagram OEA Pullup F_SELA Pulldown QA0 BW_SEL Float 0 = ~200kHz Float = ~400kHz 1 = ~800kHz F_SELA 0 ÷5 (default) 1 ÷4 nQA0 QA1 CLK Pulldown nCLK Pullup Phase Detector VCO 490 - 640 MHz nQA1 QB0 M = ÷5 (fixed) F_SELB 0 ÷5 (default) 1 ÷4 nQB0 QB1 nQB1 F_SELB Pulldown MR Pulldown IREF Pullup OEB IDT™ / ICS™ PCI EXPRESS™ JITTER ATTENUATOR 2 ICS8741004BGI REV. B SEPTEMBER 27, 2007 ICS8741004I DIFFERENTIAL-TO-LVDS/0.7V DIFFERENTIAL PCI EXPRESS™ JITTER ATTENUATOR PRELIMINARY Table 1. Pin Descriptions Number 1, 24 3, 22 4, 5 Name nQA1, QA1 VDDO QA0, nQA0 Output Power Output Type Description Differential output pair. LVDS interface levels. Output supply pins. Differential output pair. LVDS interface levels. Active High Master Reset. When logic HIGH, the internal dividers are reset causing the true outputs Q[Ax:Bx] to go LOW and the inverted outputs nQ[Ax:Bx] to go HIGH. When logic LOW, the internal dividers and the outputs are enabled. LVCMOS/LVTTL interface levels. PLL Bandwidth input. LVCMOS/LVTTL interface levels. See Table 3B. No connect. Analog supply pin. Pulldown Frequency select pins for QAx/nQAx outputs. LVCMOS/LVTTL interface levels. See Table 3C. Core supply pin. Pullup Pulldown Pullup Output enable for QAx pins. When HIGH, QAx/nQAx outputs are enabled. When LOW, the QAx/nQAx outputs are in a high impedance state. LVCMOS/LVTTL interface levels. See Table 3A. Non-inverting differential clock input. Inverting differential clock input. Power supply ground. Pullup Output enable for QBx pins. When HIGH, QBx/nQBx outputs are enabled. When LOW, the QBx/nQBx outputs are in a high impedance state. LVCMOS/LVTTL interface levels. See Table 3A. Frequency select pins for QBx/nQBx outputs. LVCMOS/LVTTL interface levels. See Table 3C. A fixed precision resistor (RREF = 475Ω) from this pin to ground provides a reference current used for differential current-mode QB0/nQB0 clock outputs. Differential output pair. HCSL interface levels. Differential output pair. HCSL interface levels. 6 MR Input Pulldown 7 8 9 10 11 12 13 14 15, 16 17 BW_SEL nc VDDA F_SELA VDD OEA CLK nCLK GND OEB Input Unused Power Input Power Input Input Input Power Input Pullup/ Pulldown 18 19 20, 21 23, 24 F_SELB IREF nQB0, QB0 QB1, nQB1 Input Input Output Output Pulldown NOTE: Pullup and Pulldown refer to internal input resistors. See Table 2, Pin Characteristics, for typical values. Table 2. Pin Characteristics Symbol CIN RPULLUP RPULLDOWN Parameter Input Capacitance Input Pullup Resistor Input Pulldown Resistor Test Conditions Minimum Typical 4 51 51 Maximum Units pF kΩ kΩ IDT™ / ICS™ PCI EXPRESS™ JITTER ATTENUATOR 3 ICS8741004BGI REV. B SEPTEMBER 27, 2007 ICS8741004I DIFFERENTIAL-TO-LVDS/0.7V DIFFERENTIAL PCI EXPRESS™ JITTER ATTENUATOR PRELIMINARY Function Tables Table 3A. Output Enable Function Table Inputs OEA 0 1 OEB 0 1 Outputs QA[0:1]/nQA[0:1] Hi-Z Enabled QB[0:1]/nQB[0:1] Hi-Z Enabled Table 3B. PLL Bandwidth Function Table Input BW_SEL 0 Float 1 PLL Bandwidth ~200kHz ~600kHz (default) ~2MHz Absolute Maximum Ratings 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. Item Supply Voltage, VDD Inputs, VI Outputs, VO Package Thermal Impedance, θJA Storage Temperature, TSTG Rating 4.6V -0.5V to VDD + 0.5V -0.5V to VDDO + 0.5V 32.1°C/W (0 mps) -65°C to 150°C DC Electrical Characteristics Table 4A. Power Supply DC Characteristics, VDD = VDDO = 3.3V ± 5%, TA = -40°C to 85°C Symbol VDD VDDA VDDO IDD IDDA IDDO Parameter Positive Supply Voltage Analog Supply Voltage Output Supply Voltage Power Supply Current Analog Supply Current Output Supply Current Test Conditions Minimum 3.135 VDD – 0.12 3.135 Typical 3.3 3.3 3.3 Maximum 3.465 VDD 3.465 45 12 80 Units V V V mA mA mA IDT™ / ICS™ PCI EXPRESS™ JITTER ATTENUATOR 4 ICS8741004BGI REV. B SEPTEMBER 27, 2007 ICS8741004I DIFFERENTIAL-TO-LVDS/0.7V DIFFERENTIAL PCI EXPRESS™ JITTER ATTENUATOR PRELIMINARY Table 4B. LVCMOS/LVTTL DC Characteristics, VDD = VDDO = 3.3V ± 5%, TA = -40°C to 85°C Symbol Parameter OEA, OEB, MR, F_SELA, F_SELB BW_SEL OEA, OEB, MR, F_SELA, F_SELB BW_SEL VIM IIH Input Mid Voltage BW_SEL F_SELA, F_SELB, MR, BW_SEL OEA, OEB MR, F_SELA, F_SELB, OEA, OEB, BW_SEL VDD = VIN = 3.465V VDD = VIN = 3.465V VDD = 3.465V, VIN = 0V VDD = 3.465V, VIN = 0V -5 -150 Test Conditions Minimum 2 VDD – 0.3 -0.3 -0.3 VDD/2 – 0.1 Typical Maximum VDD + 0.3 VDD + 0.3 0.8 +0.3 VDD/2 + 0.1 150 5 Units V V V V V µA µA µA µA VIH Input High Voltage VIL Input Low Voltage Input High Current IIL Input Low Current Table 4C. Differential DC Characteristics, VDD = VDDO = 3.3V ± 5%, TA = -40°C to 85°C Symbol IIH Parameter CLK Input High Current nCLK CLK IIL Input Low Current nCLK VPP VCMR Peak-to-Peak Voltage Common Mode Input Voltage; NOTE 1 Test Conditions VDD = VIN = 3.465V VDD = VIN = 3.465V VDD = 3.465V, VIN = 0V VDD = 3.465V, VIN = 0V -5 -150 0.15 GND + 0.5 1.3 VDD – 0.85 Minimum Typical Maximum 150 5 Units µA µA µA µA V V NOTE 1: Common mode input voltage is defined as VIH. Table 4D. LVDS DC Characteristics, VDD = VDDO = 3.3V ± 5%, TA = -40°C to 85°C Symbol VOD ∆VOD VOS ∆VOS Parameter Differential Output Voltage VOD Magnitude Change Offset Voltage VOS Magnitude Change 1.2 1.35 Test Conditions Minimum 290 Typical 390 Maximum 490 50 1.5 50 Units mV mV V mV IDT™ / ICS™ PCI EXPRESS™ JITTER ATTENUATOR 5 ICS8741004BGI REV. B SEPTEMBER 27, 2007 ICS8741004I DIFFERENTIAL-TO-LVDS/0.7V DIFFERENTIAL PCI EXPRESS™ JITTER ATTENUATOR PRELIMINARY AC Electrical Characteristics Table 5. 0.7V Differential AC Characteristics, VDD = VDDO = 3.3V ± 5%, TA = -40°C to 85°C Parameter fMAX tjit(cc) tsk(b) VHIGH VLOW VOVS VUDS Vrb VCROSS ∆VCROSS Symbol Output Frequency Cycle-to-Cycle Jitter; NOTE 1 Bank Skew, NOTE 2 Output Voltage High Output Voltage Low Max. Voltage, Overshoot Min. Voltage, Undershoot Ringback Voltage Absolute Crossing Voltage Total Variation of VCROSS over all edges Output Rise/Fall Time Rise/Fall Time Variation Rise/Fall Matching Output Duty Cycle QBx/nQBx QBx/nQBx QBx/nQBx QBx/nQBx QBx/nQBx QBx/nQBx QBx/nQBx QBx/nQBx QAx/nQAx ∆tR / ∆t F tRFM odc QBx/nQBx QBx/nQBx 48 @ 0.7V Swing @ 0.7V Swing measured between 0.175V to 0.525V 20% to 80% 175 250 250 -0.3 0.2 550 140 700 600 125 20 52 530 -150 VHIGH + 0.35 Test Conditions Minimum 98 Typical Maximum 160 35 30 870 Units MHz ps ps mV mV V V V mV mV ps ps ps % % tR / tF NOTE 1: This parameter is defined in accordance with JEDEC Standard 65. NOTE 2: Defined as skew within a bank of outputs at the same voltage and with equal load conditions. IDT™ / ICS™ PCI EXPRESS™ JITTER ATTENUATOR 6 ICS8741004BGI REV. B SEPTEMBER 27, 2007 ICS8741004I DIFFERENTIAL-TO-LVDS/0.7V DIFFERENTIAL PCI EXPRESS™ JITTER ATTENUATOR PRELIMINARY Parameter Measurement Information VDD, VDDO VDDA , 33Ω 49.9Ω 33Ω 50Ω Measurement Point VDD, VDDO SCOPE Qx VDDA 3.3V±5% POWER SUPPLY + Float GND – HCSL 50Ω 49.9Ω RREF = 475Ω 2pF Measurement Point LVDS nQx GND 2pF 3.3V HCSL Output Load AC Test Circuit 3.3V LVDS Output Load AC Test Circuit VDD nQX0 QX0 V Cross Points nCLK OD nQX1 QX1 CLK V OS t sk(b) GND Where X is either Bank A or Bank B Differential Input Level Bank Skew nQA[0:1], nQB[0:1] QA[0:1], QB[0:1] nQA[0:1], nQB[0:1] QA[0:1], QB[0:1] t PW t PERIOD t cycle n ➤ t jit(cc) = t cycle n – t cycle n+1 1000 Cycles Cycle-to-Cycle Jitter IDT™ / ICS™ PCI EXPRESS™ JITTER ATTENUATOR ➤ ➤ t cycle n+1 ➤ odc = t PW t PERIOD x 100% Output Duty Cycle/Pulse Width/Period 7 ICS8741004BGI REV. B SEPTEMBER 27, 2007 ICS8741004I DIFFERENTIAL-TO-LVDS/0.7V DIFFERENTIAL PCI EXPRESS™ JITTER ATTENUATOR PRELIMINARY Parameter Measurement Information, continued 0.525V Clock 0.175V Outputs 0.525V VSW I N G 0.175V Clock Outputs 20% 80% 80% VOD 20% tF tR tF tR HCSL Output Rise/Fall Time LVDS Output Rise/Fall Time VDD VDD ➤ ➤ out out out ➤ VOS/∆ VOS Differential Output Voltage Setup Offset Voltage Setup IDT™ / ICS™ PCI EXPRESS™ JITTER ATTENUATOR 8 ICS8741004BGI REV. B SEPTEMBER 27, 2007 ➤ DC Input LVDS ➤ DC Input out 100 VOD/∆ VOD LVDS ➤ ICS8741004I DIFFERENTIAL-TO-LVDS/0.7V DIFFERENTIAL PCI EXPRESS™ JITTER ATTENUATOR PRELIMINARY Application Information Power Supply Filtering Technique As in any high speed analog circuitry, the power supply pins are vulnerable to random noise. To achieve optimum jitter performance, power supply isolation is required. The ICS8741004I 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 0.01µF bypass capacitors should be used for each pin. Figure 1 illustrates this for a generic VDD pin and also shows that VDDA requires that an additional 10Ω resistor along with a 10µF bypass capacitor be connected to the VDDA pin. 3.3V VDD .01µF VDDA .01µF 10µF 10Ω Figure 1. Power Supply Filtering Wiring the Differential Input to Accept Single Ended Levels Figure 2 shows how the differential input can be wired to accept single ended levels. The reference voltage V_REF = VDD/2 is generated by the bias resistors R1, R2 and C1. This bias circuit should be located as close as possible to the input pin. The ratio of R1 and R2 might need to be adjusted to position the V_REF in the center of the input voltage swing. For example, if the input clock swing is only 2.5V and VDD = 3.3V, V_REF should be 1.25V and R2/R1 = 0.609. VDD R1 1K Single Ended Clock Input CLK V_REF nCLK C1 0.1u R2 1K Figure 2. Single-Ended Signal Driving Differential Input IDT™ / ICS™ PCI EXPRESS™ JITTER ATTENUATOR 9 ICS8741004BGI REV. B SEPTEMBER 27, 2007 ICS8741004I DIFFERENTIAL-TO-LVDS/0.7V DIFFERENTIAL PCI EXPRESS™ JITTER ATTENUATOR PRELIMINARY Differential Clock Input Interface The CLK /nCLK accepts LVDS, LVPECL, LVHSTL, SSTL, HCSL and other differential signals. Both VSWING and VOH must meet the VPP and VCMR input requirements. Figures 3A to 3F show interface examples for the HiPerClockS CLK/nCLK input driven by the most common driver types. The input interfaces suggested here are examples only. Please consult with the vendor of the driver component to confirm the driver termination requirements. For example, in Figure 3A, the input termination applies for IDT HiPerClockS open emitter LVHSTL drivers. If you are using an LVHSTL driver from another vendor, use their termination recommendation. 3.3V 3.3V 1.8V Zo = 50Ω Zo = 50Ω CLK Zo = 50Ω Zo = 50Ω nCLK nCLK CLK 3.3V LVPECL HiPerClockS Input R1 50 R2 50 HiPerClockS Input LVHSTL IDT HiPerClockS LVHSTL Driver R1 50 R2 50 R2 50 Figure 3A. HiPerClockS CLK/nCLK Input Driven by an IDT Open Emitter HiPerClockS LVHSTL Driver Figure 3B. HiPerClockS CLK/nCLK Input Driven by a 3.3V LVPECL Driver 3.3V 3.3V 3.3V Zo = 50Ω CLK CLK Zo = 50Ω nCLK R1 100 R3 125 R4 125 3.3V 3.3V Zo = 50Ω LVPECL R1 84 R2 84 HiPerClockS Input Zo = 50Ω nCLK LVDS Receiver Figure 3C. HiPerClockS CLK/nCLK Input Driven by a 3.3V LVPECL Driver Figure 3D. HiPerClockS CLK/nCLK Input Driven by a 3.3V LVDS Driver 2.5V 3.3V 2.5V R3 120 Zo = 60Ω R4 120 2.5V 3.3V *R3 33 Zo = 50Ω CLK Zo = 50Ω nCLK CLK Zo = 60Ω nCLK HCSL *R4 33 R1 50 R2 50 HiPerClockS Input SSTL R1 120 R2 120 HiPerClockS *Optional – R3 and R4 can be 0Ω Figure 3E. HiPerClockS CLK/nCLK Input Driven by a 3.3V HCSL Driver Figure 3F. HiPerClockS CLK/nCLK Input Driven by a 2.5V SSTL Driver IDT™ / ICS™ PCI EXPRESS™ JITTER ATTENUATOR 10 ICS8741004BGI REV. B SEPTEMBER 27, 2007 ICS8741004I DIFFERENTIAL-TO-LVDS/0.7V DIFFERENTIAL PCI EXPRESS™ JITTER ATTENUATOR PRELIMINARY Recommendations for Unused Input and Output Pins Inputs: LVCMOS 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 1kΩ resistor can be used. Outputs: Differential Outputs All unused differential outputs can be left floating. We recommend that there is no trace attached. Both sides of the differential output pair should either be left floating or terminated. LVDS Outputs All unused LVDS output pairs can be either left floating or terminated with 100Ω across. If they are left floating, we recommend that there is no trace attached. LVDS Driver Termination A general LVDS interface is shown in Figure 4. In a 100Ω differential transmission line environment, LVDS drivers require a matched load termination of 100Ω across near the receiver input. For a multiple LVDS outputs buffer, if only partial outputs are used, it is recommended to terminate the unused outputs. 3.3V 3.3V 50Ω LVDS Driver R1 100Ω + – 50Ω 100Ω Differential Transmission Line Figure 4. Typical LVDS Driver Termination IDT™ / ICS™ PCI EXPRESS™ JITTER ATTENUATOR 11 ICS8741004BGI REV. B SEPTEMBER 27, 2007 ICS8741004I DIFFERENTIAL-TO-LVDS/0.7V DIFFERENTIAL PCI EXPRESS™ JITTER ATTENUATOR PRELIMINARY Recommended Termination Figure 5A is the recommended termination for applications which require the receiver and driver to be on a separate PCB. All traces should be 50Ω impedance. Figure 5A. Recommended Termination Figure 5B is the recommended termination for applications which require a point to point connection and contain the driver and receiver on the same PCB. All traces should all be 50Ω impedance. Figure 5B. Recommended Termination IDT™ / ICS™ PCI EXPRESS™ JITTER ATTENUATOR 12 ICS8741004BGI REV. B SEPTEMBER 27, 2007 ICS8741004I DIFFERENTIAL-TO-LVDS/0.7V DIFFERENTIAL PCI EXPRESS™ JITTER ATTENUATOR PRELIMINARY Thermal Release Path The expose metal pad provides heat transfer from the device to the P.C. board. The expose metal pad is ground pad connected to ground plane through thermal via. The exposed pad on the device to the exposed metal pad on the PCB is contacted through solder as shown in Figure 6. For further information, please refer to the Application Note on Surface Mount Assembly of Amkor’s Thermally /Electrically Enhance Leadframe Base Package, Amkor Technology. SOLDER PIN EXPOSED HEAT SLUG SOLDER PIN SOLDER PIN PAD GROUND PLANE THERMAL VIA LAND PATTERN (GROUND PAD) PIN PAD Figure 6. P.C. Board for Exposed Pad Thermal Release Path Example IDT™ / ICS™ PCI EXPRESS™ JITTER ATTENUATOR 13 ICS8741004BGI REV. B SEPTEMBER 27, 2007 ICS8741004I DIFFERENTIAL-TO-LVDS/0.7V DIFFERENTIAL PCI EXPRESS™ JITTER ATTENUATOR PRELIMINARY Schematic Example Figure 7 shows an example of ICS8741004I application schematic. In this example, the device is operated at VDD = VDDO = 3.3V. Two examples of LVDS terminations and two examples of HCSL terminations are shown in this schematic. The input is driven by a 3.3V LVPECL driver. The decoupling capacitors should be located as close as possible to the power pin. /QA1 Zo = 50 Ohm Logic Control Input Examples VDD R1 100 QA1 Zo = 50 Ohm + Set Logic Input to '1' RU1 1K VDD Set Logic Input to '0' RU2 Not Install To Logic Input pins RD1 Not Install RD2 1K To Logic Input pins Zo = 50 Ohm Alternate LVDS Termination R2 50 + QA0 VDD = 3.3V U1 VDDO R4 10 QA0 /QA0 MR BW_SEL /QA0 Zo = 50 Ohm C2 10uF C3 0.01u F_SELA OEA 1 2 3 4 5 6 7 8 9 10 11 12 /QA1 QA1 VDDO QA0 /QA0 MR BW_SEL nc VDDA F_SELA VDD OEA /QB1 QB1 VDDO QB0 /QB0 IREF F_SELB OEB GND GND /CLK CLK 24 23 22 21 20 19 18 17 16 15 14 13 /QB1 QB1 VDDO QB0 /QB0 F_SELB OEB C1 0.1uF R3 50 - R5 475 VDD=3.3V VDDO=3.3V C4 0.1u ICS8741004I R6 33 Zo = 50 TL4 Zo = 50 TL6 nCLK R8 50 R9 50 + - Zo = 50 Ohm CLK R7 33 Zo = 50 Ohm LVPECL Driv er R10 50 R11 50 Recommended for PCI Express Add-In Card HCSL Termination (U1:3)VDDO (U1:22) C5 .1uf C6 .1uf R12 50 QB0 /QB0 Zo = 50 TL8 Zo = 50 TL9 R13 50 R14 50 + - Recommended for PCI Express Point-to-Point Connection Figure 7. ICS8741004I Schematic Example IDT™ / ICS™ PCI EXPRESS™ JITTER ATTENUATOR 14 ICS8741004BGI REV. B SEPTEMBER 27, 2007 ICS8741004I DIFFERENTIAL-TO-LVDS/0.7V DIFFERENTIAL PCI EXPRESS™ JITTER ATTENUATOR PRELIMINARY Power Considerations This section provides information on power dissipation and junction temperature for the ICS8741004I. Equations and example calculations are also provided. 1. Power Dissipation. The total power dissipation for the ICS741004I is the sum of the core power plus the analog 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 + IDDA_MAX) = 3.465V * (45mA + 12mA) = 197.5mW Power (LVDS_output)MAX = VDDO_MAX * IDDO_MAX = 3.465V * 80mA = 227.2mW Power (HCSL_output)MAX = 45.65mW * 2 = 91.3mW Total Power_MAX = (3.465V, with all outputs switching) = 197.5mW + 277.2mW + 91.3mW = 556mW 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 HiPerClockS 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 no air flow and a multi-layer board, the appropriate value is 32.1°C/W per Table 6 below. Therefore, Tj for an ambient temperature of 85°C with all outputs switching is: 85°C + 0.556W * 32.1°C/W = 102.8°C. This is 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 Lead TSSOP, E-Pad, Forced Convection θJA Vs. Air Flow Meters per Second Multi-Layer PCB, JEDEC Standard Test Boards 0 32.1°C/W 1 25.5°C/W 2.5 24.0°C/W IDT™ / ICS™ PCI EXPRESS™ JITTER ATTENUATOR 15 ICS8741004BGI REV. B SEPTEMBER 27, 2007 ICS8741004I DIFFERENTIAL-TO-LVDS/0.7V DIFFERENTIAL PCI EXPRESS™ JITTER ATTENUATOR PRELIMINARY 3. Calculations and Equations. The purpose of this section is to calculate power dissipation on the IC per HCSL output pair. HCSL output driver circuit and termination are shown in Figure 8. VDD O VOU T RL 50 IC Figure 8. LVHSTL 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 VCCO – 2V. Pd_H is power dissipation when the output drives high. Pd_L is the power dissipation when the output drives low. Pd_H = (VOH_MAX /RL) * (VDD_MAX – VOH_MAX) Pd_L = (VOL_MIN /RL) * (VDD_MAX – VOL_MIN) Pd_H = (0.85V /50Ω) * (3.465V – 0.87V) = 44.1mW Pd_L = (0.15V/50Ω) * 0.15V = 0.45mW Total Power Dissipation per output pair = Pd_H + Pd_L = 45mW IDT™ / ICS™ PCI EXPRESS™ JITTER ATTENUATOR 16 ICS8741004BGI REV. B SEPTEMBER 27, 2007 ICS8741004I DIFFERENTIAL-TO-LVDS/0.7V DIFFERENTIAL PCI EXPRESS™ JITTER ATTENUATOR PRELIMINARY Reliability Information Table 7. θJA vs. Air Flow Table for a 24 Lead TSSOP, E-Pad θJA vs. Air Flow Meters per Second Multi-Layer PCB, JEDEC Standard Test Boards 0 32.1°C/W 1 25.5°C/W 2.5 24.0°C/W Transistor Count The transistor count for ICS8741004I is: 1318 IDT™ / ICS™ PCI EXPRESS™ JITTER ATTENUATOR 17 ICS8741004BGI REV. B SEPTEMBER 27, 2007 ICS8741004I DIFFERENTIAL-TO-LVDS/0.7V DIFFERENTIAL PCI EXPRESS™ JITTER ATTENUATOR PRELIMINARY Package Outline and Package Dimension Package Outline - G Suffix for 24 Lead TSSOP, E-Pad Table 9. Package Dimensions Symbol N A A1 A2 b b1 c c1 D E E1 e L P P1 α ααα bbb All Dimensions in Millimeters Minimum Nominal Maximum 24 1.10 0.05 0.15 0.85 0.90 0.95 0.19 0.30 0.19 0.22 0.25 0.09 0.20 0.09 0.127 0.16 7.70 7.90 6.40 Basic 4.30 4.40 4.50 0.65 Basic 0.50 0.60 0.70 5.0 5.5 3.0 3.2 0° 8° 0.076 0.10 IDT™ / ICS™ PCI EXPRESS™ JITTER ATTENUATOR 18 ICS8741004BGI REV. B SEPTEMBER 27, 2007 ICS8741004I DIFFERENTIAL-TO-LVDS/0.7V DIFFERENTIAL PCI EXPRESS™ JITTER ATTENUATOR PRELIMINARY Ordering Information Table 9. Ordering Information Part/Order Number 8741004BGI 8741004BGIT 8741004BGILF 8741004BGILFT Marking ICS8741004BGI ICS8741004BGI ICS8741004BIL ICS8741004BIL Package 24 Lead TSSOP, E-Pad 24 Lead TSSOP, E-Pad “Lead-Free” 24 Lead TSSOP, E-Pad “Lead-Free” 24 Lead TSSOP, E-Pad Shipping Packaging Tray 2500 Tape & Reel Tray 2500 Tape & Reel Temperature -40°C to 85°C -40°C to 85°C -40°C to 85°C -40°C to 85°C NOTE: Parts that are ordered with an "LF" suffix to the part number are the Pb-Free configuration and are RoHS compliant. While the information presented herein has been checked for both accuracy and reliability, Integrated Device Technology (IDT) assumes no responsibility for either its use or for the 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 IDT. IDT reserves the right to change any circuitry or specifications without notice. IDT does not authorize or warrant any IDT product for use in life support devices or critical medical instruments. IDT™ / ICS™ PCI EXPRESS™ JITTER ATTENUATOR 19 ICS8741004BGI REV. B SEPTEMBER 27, 2007 ICS871004I DIFFERENTIAL-TO-LVDS/0.7V DIFFERENTIAL PCI EXPRESS™ JITTER ATTENUATOR PRELIMINARY Innovate with IDT and accelerate your future networks. Contact: www.IDT.com For Sales 800-345-7015 408-284-8200 Fax: 408-284-2775 For Tech Support netcom@idt.com 480-763-2056 Corporate Headquarters Integrated Device Technology, Inc. 6024 Silver Creek Valley Road San Jose, CA 95138 United States 800 345 7015 +408 284 8200 (outside U.S.) Asia Pacific and Japan Integrated Device Technology Singapore (1997) Pte. Ltd. Reg. No. 199707558G 435 Orchard Road #20-03 Wisma Atria Singapore 238877 +65 6 887 5505 Europe IDT Europe, Limited 321 Kingston Road Leatherhead, Surrey KT22 7TU England +44 (0) 1372 363 339 Fax: +44 (0) 1372 378851 www.IDT.com © 2007 Integrated Device Technology, Inc. All rights reserved. Product specifications subject to change without notice. IDT and the IDT logo are trademarks of Integrated Device Technology, Inc. Accelerated Thinking is a service mark of Integrated Device Technology, Inc. All other brands, product names and marks are or may be trademarks or registered trademarks used to identify products or services of their respective owners. Printed in USA