LCK4310

LCK4310 AGERE | Alldatasheet

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April 20, 2004 LCK4310 Low-Voltage PLL Clock Driver

1 Features

I Output operating frequencies up to 1.25 GHz max. I 100 ps part–to–part skew. I 40 ps typical output–to–output skew. I Cycle-to-cycle jitter 5 ps max. I 3.3 V and 2.5 V compatible. I Internal input pulldown resistors. I Q output will default low with inputs open or at VEE. I Meets or exceeds Joint Electron Device Engineering Council (JEDEC) specification EIA®/JESD78 IC latchup test. I Moisture sensitivity level 1. I Flammability rating: UL®–94 code V–0 at 1/8 in., oxygen index 28 to 34. I Pin-for-pin compatible with ON Semiconductor® part number MC100LVE310.

2 Description

The LCK4310 is a low-voltage, low-skew 2:8 differential emitter-coupled logic (ECL) fanout buffer designed with clock distribution in mind. The device features fully differential clock paths to minimize both device and system skew. The LCK4310 offers two selectable clock inputs to allow for redundant or test clocks to be incorporated into the system clock trees. To ensure that the tight skew specification is met, it is necessary that both sides of the differential output are terminated into 50 Ω , even if only one side is being used. In most applications, all eight differential pairs will be used and therefore terminated. In the case where fewer than eight pairs are used and in order to maintain minimum skew, it is necessary to terminate at least the output pairs adjacent to the output pair being used. Failure to follow this guideline will result in small degradations of propagation delay (on the order of 10 ps—20 ps) of the outputs being used. While not catastrophic to most designs, this will result in an increase in skew. Note: The package corners isolate outputs from one anoth- er such that the guideline expressed above holds only for outputs on the same side of the package. The LCK4310, as with most ECL devices, can be operated from a positive voltage supply (V DD) in LVPECL mode. This allows the LCK4310 to be used for high-performance clock distribution in 3.3 V/2.5 V systems. Designers can take advantage of the LCK4310’s performance to distribute low- skew clocks across the backplane or the board. In a PECL environment (series or Thevenin), line terminations are typically used since they require no additional power supplies. If parallel termination is desired, a terminating voltage of V DD – 2.0 V will need to be provided. An internally generated voltage supply (VBB pin) is available to this device only. For single-ended input conditions, the unused differential input is connected to V BB as a switching reference voltage. VBB may also rebias ac coupled inputs. When used, decouple VBB and VDD via a 0.01 µF capacitor and limit current sourcing or sinking to 0.5 mA. When not used, V BB should be left open.

Low-Voltage PLL Clock Driver April 20, 2004 22 Agere Systems Inc.

3 Pin Information

3.1 Pin Diagram

Figure 3-1. 28-Pin PLCC WARNING: All VDD, VDDO, and VEE pins must be externally connected to a power supply to guarantee proper oper- ation. VEE CLK_SEL CLKa VDD CLKa VBB CLKb VDDO VDDO NC VDDO CLKb

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3.2 Pin Descriptions

Table 3-1. Pin Descriptions

3.3 Logic Symbol

Figure 3-2. Logic Symbol Pin Symbol Type I/O Description 1V DD Power — Positive Power Supply. 2 CLKa PECL I ECL Differential Input Clock. Makes input pair with CLKa. 3V BB VREFOUT O Reference Voltage Output. 4 CLKb PECL I ECL Differential Input Clock. Makes input pair with CLKb. 5 CLKb PECL I ECL Differential Input Clock. Makes input pair with CLKb. 6 NC —— No Connect. 7, 10, 12, 14, 17, 19, 21, 24 Q[7:0] PECL O ECL Differential Outputs. 8, 15, 22 V DDO Power — Positive Power Supply. 9, 11, 13, 16, 18, 20, 23, 25 Q[7:0] PECL O ECL Differential Outputs. 26 V EE Power — Negative Power Supply. 27 CLK_SEL LVTTL I ECL Input Clock Select. 0 = CLKa selected. 1 = CLKb selected. 28 CLKa PECL I ECL Differential Input Clock. Makes input pair with CLKa VBB CLKa CLKa CLKb CLKb CLK_SEL CLK_SEL Input Clock L CLKa/CLKa Selected H CLKb/CLKb Selected

Low-Voltage PLL Clock Driver April 20, 2004 44 Agere Systems Inc.

4 Absolute Maximum Ratings

Stresses which exceed the absolute maximum ratings can cause permanent damage to the device. These are absolute stress ratings only. Functional operation of the device is not implied at these or any other conditions in excess of those given in the operational sections of the data sheet. Exposure to absolute maximum ratings for extended periods of time can adversely affect device reliability. Table 4-1. Absolute Maximum Ratings

4.1 Handling Precautions

Although electrostatic discharge (ESD) protection circuitry has been designed into this device, proper precautions must be taken to avoid exposure to ESD and electrical overstress (EOS) during all handling, assembly, and test operations. Agere employs both a human-body model (HBM) and a charged-device model (CDM) qualification requirement in order to determine ESD-susceptibility limits and protection design evaluation. ESD voltage thresholds are dependent on the circuit parameters used in each of the models, as defined by JEDEC’s JESD22-A114 (HBM) and JESD22-C101 (CDM) standards. Table 4-2. ESD Tolerance Parameter Symbol Conditions Min Max Unit PECL Mode Positive Power Supply V DD VEE = 0 V 0 5 V Input Voltage: PECL Mode Positive Input Voltage VI VEE = 0 V, VI ≤ VDD 05 V Output Current I OUT Continuous surge 50 100 mA VBB Sink/Source I BB — –0.5 0.5 mA Storage Temperature Range T stg —– 6 5 1 5 0 ° C Wave Solder T SOL <2 s to 3 s at 248 °C — 265 °C Device Minimum Threshold HBM CDM LCK4310 >2,000 V >1,000 V

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4.2 Thermal Parameters (Definitions and Values)

System and circuit board level performance depends not only on device electrical characteristics, but also on device thermal characteristics. The thermal characteristics frequently determine the limits of circuit board or system performance, and they can be a major cost adder or cost avoidance factor. When the die temperature is kept below 125 °C, temperature activated failure mechanisms are minimized. The thermal parameters that Agere provides for its packages help the chip and system designer choose the best package for their applications, including allowing the system designer to thermally design and in- tegrate their systems. It should be noted that all the parameters listed below are affected, to varying degrees, by package design (including paddle size) and choice of materials, the amount of copper in the test board or system board, and system airflow. Θ JA - Junction to Air Thermal Resistance Θ JA is a number used to express the thermal performance of a part under JEDEC standard natural convection conditions. Θ JA is calculated using the following formula: Θ JA = (TJ – Tamb) / P; where P = power Θ JMA - Junction to Moving Air Thermal Resistance Θ JMA is effectively identical to Θ JA but represents performance of a part mounted on a JEDEC four layer board inside a wind tunnel with forced air convection. Θ JMA is reported at airflows of 200 LFPM and 500 LFPM (linear feet per minute), which roughly correspond to 1 m/s and 2.5 m/s (respectively). Θ JMA is calculated using the following formula: Θ JMA = (TJ – Tamb) / P Θ JC - Junction to Case Thermal Resistance Θ JC is the thermal resistance from junction to the top of the case. This number is determined by forcing nearly 100% of the heat generated in the die out the top of the package by lowering the top case temperature. This is done by placing the top of the package in contact with a copper slug kept at room temperature using a liquid refrigeration unit. Θ JC is calculated using the following formula: Θ JC = (TJ – TC) / P Table 4-3. Thermal Parameter Values Parameter Temperature °C/Watt Θ JA 63.5 Θ JMA (500 lf/m) 43.5 Θ JC 27.3

Low-Voltage PLL Clock Driver April 20, 2004 66 Agere Systems Inc.

5 Electrical Characteristics

5.1 dc Characteristics Table 5-1. LVPECL 3.3 V dc Characteristics the dc specifications shown in this table, after thermal equilibrium has been established. Parameter Symbol –40 °C 25 °C 85 °C Unit Min Typ Max Min Typ Max Min Typ Max Power Supply Current I EE — 55 60 — 55 60 — 65 70 mA Output High Voltage* * Outputs are terminated through a 50 Ω resistor to VDD – 2 V. Input High Voltage (sin- gle-ended) Input Low Voltage (sin- gle-ended) Output Voltage Reference Input High Voltage Common-mode Range (differential) † VIHCMR minimum varies 1:1 with VEE, maximum varies 1:1 with VDD. VIHCMR is defined as the range within which the V IH level may vary, with the device still meeting the propagation delay specification. The V IL level must be such that the peak-to-peak voltage is less than 1.0 V and greater than or equal to Vp-pmin. Input High Current I IH — — 150 — — 150 — — 150 µA Input Low Current I IL 0.5 — — 0.5 — — 0.5 — — µA

April 20, 2004 Low-Voltage PLL Clock Driver Agere Systems Inc. 7 Table 5-2. LVPECL 2.5 V dc Characteristics the dc specifications shown in this table, after thermal equilibrium has been established. Parameter Symbol –40 °C 25 °C 85 °C Unit Min Typ Max Min Typ Max Min Typ Max Power Supply Current I EE — 55 60 — 55 60 — 65 70 mA Output High Voltage* * Outputs are terminated through a 50 Ω resistor to VDD – 2 V. Input High Voltage (single-ended) Input Low Voltage (single-ended) Output Voltage Reference Input High Voltage Common-mode Range (differential) † VIHCMR minimum varies 1:1 with VEE, maximum varies 1:1 with VDD. VIHCMR is defined as the range within which the V IH level may vary, with the device still meeting the propagation delay specification. The V IL level must be such that the peak-to-peak voltage is less than 1.0 V and greater than or equal to Vp-pmin. Input High Current I IH — — 150 — — 150 — — 150 µA Input Low Current I IL 0.5 — — 0.5 — — 0.5 — — µA

Low-Voltage PLL Clock Driver April 20, 2004 88 Agere Systems Inc. 5.2 ac Characteristics Table 5-3. ac Characteristics Figure 5-1. Typical Termination for Output Driver and Device Evaluation Parameter Symbol –40 °C 25 °C 85 °C Unit Min Typ Max Min Typ Max Min Typ Max Maximum Toggle Frequency Propagation Delay to Output: In (differential)* In (single-ended)† * The differential propagation delay is defined as the delay from the crossing points of the differential input signals to the crossing point of the differential output signals. † The single-ended propagation delay is defined as the delay from the 50% point of the input signal to the 50% point of the out put signal. tPLH tPHL 525 500 725 750 550 550 750 800 575 600 775 850 ps Within Device Skew‡ ‡ The within device skew is defined as the worst case difference between any two similar delay paths within a single device. Part-to-part Skew‡ (differential) tSKEW — — 100 — — 100 — — 100 ps Jitter JIT cyc-cyc —— 5 —— 5 —— 5 p s Input Swing§ § Vp-pmin is defined as the minimum input differential voltage which will cause no increase in the propagation delay. The V p-pmin is ac limited for the LCK4310 as a differential input as low as 50 mV will still produce full ECL levels at the output. Vp-p 0.500 — 1 0.500 — 1 0.500 — 1 V Output Rise/Fall Time (20%—80%) tr/tf 200 — 600 200 — 600 200 — 600 ps VEE Q Qb DEVICE DRIVER D Db DEVICE RECEIVER VEE = VDD – 2.0 V 50 Ω 50 Ω

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6 Outline Diagrams

Dimensions are in millimeters. 5-2608 (F)

1.27 TYP

0.330/0.533 0.10 SEATING PLANE

0.51 MIN

4.572 MAX 12 18 41 2 6 12.446 ± 0.127 PIN #1 IDENTIFIER ZONE 11.506 ± 0.076 11.506 ± 0.076 12.446 ± 0.127

Copyright © 2004 Agere Systems Inc. All Rights Reserved April 20, 2004 DS04-169LCK (Replaces DS03-158LCK) Agere Systems Inc. reserves the right to make changes to the product(s) or information contained herein without notice. No liability is assumed as a result of their use or application. Agere is a registered trademark of Agere Systems Inc. Agere Systems and the Agere logo are trademarks of Agere Systems Inc. For additional information, contact your Agere Systems Account Manager or the following: INTERNET: http://www.agere.com E-MAIL: docmaster@agere.com N. AMERICA: Agere Systems Inc., Lehigh Valley Central Campus, Room 10A-301C, 1110 American Parkway NE, Allentown, PA 18109-9138 1-800-372-2447, FAX 610-712-4106 (In CANADA: 1-800-553-2448, FAX 610-712-4106) ASIA: Agere Systems Hong Kong Ltd., Suites 3201 & 3210-12, 32/F, Tower 2, The Gateway, Harbour City, Kowloon Tel. (852) 3129-2000, FAX (852) 3129-2020 CHINA: (86) 21-54614688 (Shanghai), (86) 755-25881122 (Shenzhen) JAPAN: (81) 3-5421-1600 (Tokyo), KOREA: (82) 2-767-1850 (Seoul), SINGAPORE: (65) 6778-8833, TAIWAN: (886) 2-2725-5858 (Taipei) EUROPE: Tel. (44) 1344 296 400 LCK4310 Data Sheet Low-Voltage PLL Clock Driver April 20, 2004

7 Ordering Information

EIA is a registered trademark of Electronic Industries Association. UL is a registered trademark of Underwriters Laboratories, Inc. ON Semiconductor is a registered trademark of Semiconductor Components Industries, L.L.C. Table 7-1. Ordering Information Device Part Number Pin Count Package Type Comcode LCK4310 LCK4310GF-DB 28 PLCC Reel 700020216 LCK4310GF-DT 28 PLCC Tape 700020217