SEMICONDUCTOR TECHNICAL DATA 4-BIT PARALLEL/ SERIAL CONVERTER

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1 SEMICONUCTO TECHNICAL ATA The MCE/E446 is an integrated 4-bit parallel to serial data converter. The device is designed to operate for NZ data rates of up to.3gb/s. The chip generates a divide by 4 and a divide by 8 clock for both 4-bit conversion and a two chip 8-bit conversion function. The conversion sequence was chosen to convert the parallel data into a serial stream from bit to 3. A serial input is provided to cascade two E446 devices for 8 bit conversion applications. Note that the serial output data clocks off of the negative input clock transition. On Chip Clock 4 and 8.5 Gb/s Typical ata ate Capability ifferential Clock and Serial Inputs BB Output for Single-ended Input Applications Asynchronous ata Synchronization Mode Select to Expand to 8 Bits Internal 75kΩ Input Pulldown esistors Extended E EE ange of -4.2 to BIT PAALLEL/ SEIAL CONETE The SYNC input will asynchronously reset the internal clock circuitry. This pin allows the user to reset the internal clock conversion unit and thus select the start of the conversion process. FN SUFFIX PLASTIC PACKAGE CASE The MOE input is used to select the conversion mode of the device. With the MOE input LOW, or open, the device will function as a 4-bit converter. When the mode input is driven HIGH the internal load clock will change on every eighth clock cycle thus allowing for an 8-bit conversion scheme using two E446 s. When cascaded in an 8-bit conversion scheme the devices will not operate at the.3gb/s data rate of a single device. efer to the applications section of this data sheet for more information on cascading the E446. For lower data rate applications a BB reference voltage is supplied for single-ended inputs. When operating at clock rates above 5MHz differential input signals are recommended. For single-ended inputs the BB pin is tied to the inverting differential input and bypassed via a.µf capacitor. The BB provides the switching reference for the input differential amplifier. The BB can also be used to AC couple an input signal, for more information on AC coupling refer to the interfacing section of the design guide in the ECLinPS data book. PIN NAMES Pin Function Pinout: 28-Lead PLCC (Top iew) 2 3 MOE NC NC 3,,,, MOE SYNC ifferential Serial ata Input Parallel ata Inputs ifferential Serial ata Output ifferential Clock Inputs ifferential 4 Clock Output ifferential 8 Clock Output Conversion Mode 4-Bit/8-Bit Conversion Synchronizing Input BB EE NC NC CC FUNCTION TABLES 2 4 Mode Conversion 3 3 CCO L H 4-Bit 8-Bit SYNC NC CCO CCO CCO 7/96 Motorola, Inc E 2

2 MCE446 MCE446 LOGIC IAGAM 3 2 LOA PULSE GENEATO Mode elay 4 8 SYNC MOTOOLA 2 2 L4 ev 4

3 MCE446 MCE446 C CHAACTEISTICS (EE = EE(min) to EE(max); CC = CCO = GN) C 25 C 85 C Symbol Characteristic Min Typ Max Min Typ Max Min Typ Max Unit Condition IIH Input HIGH Current µa OH Output HIGH oltage E ( Only) E ( Only) BB Output eference oltage E E IEE Power Supply Current E E The maximum OH limit was relaxed from standard ECL due to the high frequency output design. All other outputs are specified with the standard E and E OH levels ma AC CHAACTEISTICS (EE = EE(min) to EE(max); CC = CCO = GN) C 25 C 85 C Symbol Characteristic Min Typ Max Min Typ Max Min Typ Max Unit Condition FMAX Max Conversion Frequency Gb/s NZ tplh tphl Propagation elay to Output to to to SYNC to, ts Setup Time2, n ps th Hold Time2, n ps t eset ecovery Time SYNC ps tpw Min Pulse Width, M ps ps tr tf ise/fall Times Other ps 2% - 8%. Propagation delays measured from negative going clock edge. 2. elative to negative clock edge. Timing iagrams ESET Timing iagram A. 4: Parallel to Serial Conversion L4 ev MOTOOLA

4 MCE446 MCE446 Applications Information The MCE/E446 is an integrated 4: parallel to serial converter. The chip is designed to work with the E445 device to provide both transmission and receiving of a high speed serial data path. The E446 can convert 4 bits of data into a.3gb/s NZ data stream. The device features a SYNC input which allows the user to reset the internal clock circuitry and restart the conversion sequence (see timing diagram A). The E446 features a differential serial input and internal divide by 8 circuitry to facilitate the cascading of two devices to build a 8: multiplexer. Figure illustrates the architecture for a 8: multiplexer using two E446 s; the timing diagram for this configuration can be found on the following page. Notice the serial outputs () of the lower order converter feed the serial inputs of the the higher order device. This feed through of the serial inputs bounds the upper end of the frequency of operation. The clock to serial output propagation delay plus the setup time of the serial input pins must fit into a single clock period for the cascade architecture to function properly. Using the worst case values for these two parameters from the data sheet, TP to = 48ps and ts for = 2ps, yields a minimum period of 28ps or a clock frequency of 78MHz. The clock frequency is somewhat lower than that of a single converter, to increase this frequency some games can be played with the clock input of the higher order E446. By delaying the clock feeding E446A relative to the clock of E446B the frequency of operation can be increased. CLOCK Tpd to E446B Parallel ata ps ps 6ps E446A Figure. Cascaded 8: Converter Architecture Serial ata 6ps ESET (B) 5 (B) 6 (2B) 7 (3B) Timing iagram B. 8: Parallel to Serial Conversion MOTOOLA 2 4 L4 ev 4

5 MCE446 MCE446 OUTLINE IMENSIONS FN SUFFIX PLASTIC PLCC PACKAGE CASE ISSUE -N- Y BK B U.7 (.8) M T L M S N S.7 (.8) M T L M S N S -M- -L- Z 28 W X IEW - G. (.25) S T L M S N S Z A.7 (.8) M T L M S N S.7 (.8) M T L M S N S H.7 (.8) M T L M S N S C E K G G. (.25) S T L M S N S J -T- IEW S.4 (.) SEATING PLANE K IEW S F.7 (.8) M T L M S N S NOTES:. ATUMS -L-, -M-, AN -N- ETEMINE WHEE TOP OF LEA SHOULE EXITS PLASTIC BOY AT MOL PATING LINE. 2. IM G, TUE POSITION TO BE MEASUE AT ATUM -T-, SEATING PLANE. 3. IM AN U O NOT INCLUE MOL FLASH. ALLOWABLE MOL FLASH IS. (.25) PE SIE. 4. IMENSIONING AN TOLEANCING PE ANSI Y4.5M, CONTOLLING IMENSION: INCH. 6. THE PACKAGE TOP MAY BE SMALLE THAN THE PACKAGE BOTTOM BY UP TO.2 (.3). IMENSIONS AN U AE ETEMINE AT THE OUTEMOST EXTEMES OF THE PLASTIC BOY EXCLUSIE OF MOL FLASH, TIE BA BUS, GATE BUS AN INTELEA FLASH, BUT INCLUING ANY MISMATCH BETWEEN THE TOP AN BOTTOM OF THE PLASTIC BOY. 7. IMENSION H OES NOT INCLUE AMBA POTUSION O INTUSION. THE AMBA POTUSION(S) SHALL NOT CAUSE THE H IMENSION TO BE GEATE THAN.37 (.94). THE AMBA INTUSION(S) SHALL NOT CAUSE THE H IMENSION TO BE SMALLE THAN.25 (.635). IM A B C E F G H J K U W X Y Z G K INCHES MIN MAX BSC MILLIMETES MIN MAX BSC L4 ev MOTOOLA

6 MCE446 MCE446 Motorola reserves the right to make changes without further notice to any products herein. Motorola makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does Motorola assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation consequential or incidental damages. Typical parameters which may be provided in Motorola data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including Typicals must be validated for each customer application by customer s technical experts. Motorola does not convey any license under its patent rights nor the rights of others. Motorola products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the Motorola product could create a situation where personal injury or death may occur. Should Buyer purchase or use Motorola products for any such unintended or unauthorized application, Buyer shall indemnify and hold Motorola and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that Motorola was negligent regarding the design or manufacture of the part. Motorola and are registered trademarks of Motorola, Inc. Motorola, Inc. is an Equal Opportunity/Affirmative Action Employer. How to reach us: USA/EUOPE/Locations Not Listed: Motorola Literature istribution; JAPAN: Nippon Motorola Ltd.; Tatsumi SP JLC, 6F Seibu Butsuryu Center, P.O. Box 292; Phoenix, Arizona or Tatsumi Koto Ku, Tokyo 35, Japan MFAX: MFAX@ .sps.mot.com TOUCHTONE ASIA/PACIFIC: Motorola Semiconductors H.K. Ltd.; 8B Tai Ping Industrial Park, INTENET: NET.com 5 Ting Kok oad, Tai Po, N.T., Hong Kong MOTOOLA 2 6 MCE446/ L4 ev 4