UCC5510 Low Voltage Differential (LVD/SE) SCSI 9 Line Terminator FEATURES DESCRIPTION • Auto Selection Multi-Mode Single Ended or Low Voltage Differential Termination The UCC5510 Multi-Mode Low Voltage Differential and Single Ended Terminator is specially designed for automatic termination of SingleEnded or Low Voltage Differential SCSI Bus. The Multi-Mode operation of this device allows for a transition system design for the next generation SCSI Parallel Interface (SPI-2). Compliant with SPI-2, with SPI and Fast20 the UCC5510 incorporates all the functions necessary to properly terminate the SCSI Bus and has internal thermal shut down and short circuit limiting. • 3.0V to 5.25V Operation • Differential Failsafe Bias • Thermal Packaging for Low Junction Temperature and Better MTBF • Master/Slave Inputs • Supports Active Negation • 3pF Channel Capacitance BLOCK DIAGRAM SOURCE 5 < 15mA SINK 200µA MAXIMUM (NOISE LOAD) TRMPWR 38 +VDD REF 1.3V 20 DIFFSENS MSTR/SLV 19 1.3V ± –0.1V 2.2 > 1.9V DEVICE MODE SELECT LOGIC DIFFB 21 0.7 > 0.6V 110 REF 2.7V 125 +50mV TO +62.5mV 52 REF 1.25V 5 L1– 4 L1+ 32 L9– 31 L9+ 52 HS/GND 8 HS/GND 28 HS/GND 27 110 125 +50mV TO +62.5mV 52 HS/GND 26 HS/GND 10 HS/GND 9 GND 52 SWITCHES UP ARE SINGLE ENDED SWITCHES DOWN ARE LOW VOLTAGE DIFFERENTIAL 18 SE GND SWITCH 1 Circuit Design Patented SLUS332A - OCTOBER 1999 REG UDG-98033 UC5510 CONNECTION DIAGRAM ABSOLUTE MAXIMUM RATINGS SSOP-36 (Top View) MWP Package TRMPWR Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6V Signal Line Voltage . . . . . . . . . . . . . . . . . . . . . 0V to TRMPWR Package Power Dissipation . . . . . . . . . . . . . . . . . . . . . . . . . 2W Storage Temperature . . . . . . . . . . . . . . . . . . . –65°C to +150°C Junction Temperature . . . . . . . . . . . . . . . . . . . –55°C to +150°C Lead Temperature (Soldering, 10sec.) . . . . . . . . . . . . . +300°C RECOMMENDED OPERATING CONDITIONS TRMPWR Voltage . . . . . . . . . . . . . . . . . . . . . . . 3.0V TO 5.25V All voltages are with respect to pin 1. Currents are positive into, negative out of the specified terminal. Consult Packaging Section of the Databook for thermal limitations and considerations of packages. REG 1 36 N/C 2 35 N/C N/C 3 34 N/C L1+ 4 33 N/C L1– 5 32 L9– L2+ 6 31 L9+ L2– 7 30 L8– HS/GND 8 29 L8+ HS/GND 9 28 HS/GND HS/GND 10 27 HS/GND L3+ 11 26 HS/GND L3– 12 25 L7– L4+ 13 24 L7+ L4– 14 23 L6– L5+ 15 22 L6+ L5– 16 21 DIFF B N/C 17 20 DIFFSENS GND 18 19 MSTR/SLV TRMPWR ELECTRICAL CHARACTERISTICS: Unless otherwise specified, TA = 0°C to 70°C, TRMPWR = 3.3V. PARAMETER TEST CONDITIONS MIN TYP MAX UNITS TRMPWR Supply Current Section TRMPWR Supply Current Disable Terminator, in DISCNCT mode. 20 mA 35 µA Regulator Section 1.25V Regulator LVD Mode 1.15 1.25 1.25V Regulator Source Current LVD Mode, Differential Sense Floating –80 –100 1.35 V mA 1.25V Regulator Sink Current LVD Mode, Differential Sense Floating 80 100 1.3V Regulator DIFFSENS 1.2 1.3 1.3V Regulator Source Current DIFFSENS 1.3V Regulator Sink Current DIFFSENS 2.7V Regulator Single Ended Mode 2.5 2.7 3 V 2.7V Regulator Source Current Single Ended Mode –200 –400 –800 mA 2.7V Regulator Sink Current Single Ended Mode 100 200 2.7V Regulator Dropout Voltage VTRMPWR – (VREG – 3.0 Min) 2 mA 1.4 V –5 –15 mA 50 200 µA 400 mA 200 mV UC5510 ELECTRICAL CHARACTERISTICS: Unless otherwise specified, TA = 0°C to 70°C, TRMPWR = 3.3V. PARAMETER TEST CONDITIONS MIN TYP MAX UNITS Differential Impedance 100 105 110 Ω Common Mode Impedance 110 125 165 Ω 125 mV Differential Termination Section Differential Bias Voltage Drivers Tri-stated 100 Common Mode Bias Output Capacitance 1.25 Single Ended Measurement to Ground (Note 1) V 3 pF Single Ended Termination Section Impedance Termination Current Signal Level 0.2V 102.3 110 117.7 Ω –21 –23 –24 mA –22.4 mA 400 nA 3 pF 60 Ω Signal Level 0.5V Output Leakage Disabled, TRMPWR = 0V to 5.25V Output Capacitance Single Ended Measurement to Ground (Note 1) Single Ended GND SW Impedance Differential Sense (DIFF B) Input Sections DIFFB Single Ended Threshold 0.6 0.7 V DIFFB Sense LVD Threshold 1.9 2.2 V –10 10 µA DIFFB Input Current VDIFFB = 0V and 3.3V Master/Slave (MSTR/SLV) Input Section MSTR/SLV Threshold 0.8 2 V MSTR/SLV Input Current –30 30 µA Note 1: Guaranteed by design. Not 100% tested in production. PIN DESCRIPTIONS DIFFB: DIFF SENSE filter pin should be connected to a 0.1µF capacitor to GND and 20k resistor to SCSI/Bus DIFF SENSE Line. negative line in differential applications for the SCSI bus. DIFFSENS: The SCSI bus DIFF SENSE line is driven to 1.3V to detect what type of devices are connected to the SCSI bus. MSTR/SLV: Mode select for the non-controlling terminator. MSTR enables the 1.3V regulator, when the terminator is enabled. Note: This function will be removed on further generations of the multimode terminators. L1+ thru L9+: Ground line for single ended or positive line for differential applications for the SCSI bus. HS/GND: Heat Sink GND. Connect to large area PC board traces to increase power dissipation capability. GND: Power Supply Return. REG: Regulator bypass, must be connected to a 4.7µF capacitor. L1– thru L9–: Signal line/active line for single ended or TRMPWR: VIN 3.0V to 5.25V supply. 3 UC5510 APPLICATION INFORMATION TRMPWR 36 TRMPWR 19 1 L1+ L1+ L1– L1– MSTR/SLV REG CONTROL LINES (9) L9+ L9– L9– DIFFSENS 20 20 DIFFSENS REG 1 20k DIFFB 21 4.7µF TRMPWR MSTR/SLV 19 L9+ 20k TRMPWR 36 21 DIFFB 0.1µF 4.7µF 0.1µF 4.7µF 4.7µF 36 TRMPWR L10+ L10+ L10– L10– TRMPWR 36 L18+ L18+ MSTR/SLV 19 L18– L18– DATA LINES + PARITY 19 MSTR/SLV 1 REG DIFFSENS 20 NO CONNECT DIFFB 21 4.7µF 36 TRMPWR REG REG 1 21 DIFFB 4.7µF L19+ L19+ L19– L19– TRMPWR 36 L27+ L27+ MSTR/SLV 19 L27– L27– 19 MSTR/SLV 1 20 DIFFSENS DATA LINES + PARITY DIFFSENS 20 NO CONNECT 20 DIFFSENS 4.7µF REG 1 4.7µF DIFFB 21 21 DIFFB UDG-98034a Figure 1. Application Drawing The master is selected by placing TRMPWR on MSTR/SLV and enabling the 1.3V regulator. The master is the only terminator connected directly to the DIFFSENS bus line. All the other terminators receive a mode signal by connecting the DIFFB pins together. in the MWP package where between L8 and L9 the balance is 0.23pF and 0.4pF respecitvely The negative (–) signal line has a higher capacitance than the positive (+) signal line. The FQP package has typically 0.2pF less capacitance than the MWP package, where the typical balance is 0.1pF except for L8 and L3, where the balance is 0.4pF. The balancing capacitor is very important during high speed operation. The typical capacitor balance between the positive (+) and negative (–) signals is 0.1pF, except UNITRODE CORPORATION 7 CONTINENTAL BLVD. • MERRIMACK, NH 03054 TEL. (603) 424-2410 • FAX (603) 424-3460 Note: The master/slave function will not be included in future Unitrode terminators. 4