SS8218 Ultra160 Multi-mode LVD/SE SCSI Terminator Features General Description Auto-selectable multi-mode Single-Ended The SS8218 Multi-mode LVD/SE SCSI terminator provides a smooth transition to the next generation of the SCSI Parallel Interface (SPI-3). It automatically senses the bus, via DIFFSENS, and switches the termination to either single-ended (SE) or low voltage differential (LVD) SCSI, dependent on which type of devices are connected to the bus. If the SS8218 detects a HVD SCSI device, it switches to a high impedance state. For a 16-bit Wide SCSI bus to be operational, three SS8218 terminators are needed. or LVD Termination Meets SCSI-1, SCSI-2, SCSI-3 SPI Ultra (Fast-20), Ultra 2(SPI-2 LVD), Ultra160 (SPI-3 LVD) standards. Supports active negation 3pF channel capacitance Thermal protection Hot-swap compatible 5% tolerance on SE and LVD termination resistance 28 and 36 pin SSOP package 28 Pin SSOP: Pin Compatible with DS2119 36 Pin SSOP: Pin Compatible with DS2118, LX5241 and UCC5630 Applications Server and workstation High-end PC Industrial PC Disk Array (RAID) SCSI cable The Multi-mode terminator contains all functions required to terminate and auto detect and switch modes for SCSI Parallel Interface (SPI) bus architectures. For the SE termination, one regulator and nine precision 110ohm resistors are used. For the LVD termination, the SS8218 integrates 18 regulated supplies with nine precision resistor strings. Pin Configuration VREF 1 36 NC 2 35 HVD NC 3 34 LVD TPWR R1+ 4 33 SE VREF 1 28 TPWR R1- 5 32 R9- R1+ 2 27 R2+ 6 31 R9+ R1- 3 26 TPWR R9- R2- 7 30 R8- R2+ R2- 4 25 NC/HS R9+ GND HS/GND 8 29 5 24 R8- HS/GND 9 28 R8+ HS/GND NC/HS GND 6 23 R8+ 10 27 HS/GND R3+ 7 22 NC/HS GND HS/GND R3+ 11 26 HS/GND R3- 8 21 R7- R3- 12 25 R7- R4+ 9 20 R7+ R4+ 13 24 R7+ R4- 10 19 R6- R4- 14 23 R6- R5+ 11 18 R6+ R5+ 15 22 R6+ R5- 16 21 DIFFB DISCNCT 17 20 DIFFSENSE GND 18 19 M/S R5- 12 17 DIFFB DISCNCT 13 16 DIFFSENSE GND 14 15 M/S 28Pin SSOP/TSSOP Rev.2.01 6/06/2003 www.SiliconStandard.com 36Pin SSOP 1 of 11 SS8218 Ordering Information PIN-PACKAGE FEATURE SS8218-S4TB SS8218-S4TR PART NUMBER TEMP. RANGE 0ºC-70ºC 0ºC-70ºC SSOP-28 pin / Tube SSOP-28 pin / Tape & Reel DISCNCT does not disable VREF DISCNCT does not disable VREF SS8218-S5TB SS8218-S5TR SS8218-D3TB SS8218-D3TR 0ºC-70ºC 0ºC-70ºC 0ºC-70ºC 0ºC-70ºC SSOP-36 pin / Tube SSOP-36 pin / Tape & Reel TSSOP-28 pin / Tube TSSOP-28 pin / Tape & Reel DISCNCT does not disable VREF DISCNCT does not disable VREF DISCNCT does not disable VREF DISCNCT does not disable VREF Note: DIFFSENSRefers to the SCSI bus signal. DIFFSENSERefers to the SS8218 pin name and internal circuitry relating to differential sensing. DIFFBRefers to the SS8218 pin name and internal circuitry relating to monitoring the DIFFSENS line. Functional Description The SS8218 is used in multi-mode active termination applications, where single ended (SE) and low voltage differential (LVD) devices might coexist. The LVD termination section consists of 18 source/sink amplifiers (VTOP, VBOT), biasing circuitry and nine precision resistor strings (RTOP, RMID, RBOT). The SE termination section consists of a 2.85V source/sink regulator with 9 precision 110ohm resistor. The DIFFSENSE section consists of a 1.3V, 5mA driver and a sensing circuit (Figure 1) and ground and placed as close as possible to the SS8218. The 8218 should be placed as close as possible to the SCSI connector to minimize signal and power trace length, thereby resulting in less input capacitance and reflections which can degrade the bus signals. The DIFFSENSE pin can drive the SCSI DIFFSENS line (when M/S is pulled high) to determine the SCSI bus operating mode. The SS8218 switches to the termination mode that is appropriate for the bus based on the value of the DIFFSENS voltage. These modes are: DIFFSENS is used to identify which types of SCSI devices are present on the bus. If the voltage on DIFFSENS is between 0-0.5V the bus is single-ended; if it is between 0.7-1.9V the bus is LVD; and if it is greater than 2.4V, the bus is HVD. LVD mode LVD termination is provided by a precision resistor string with two amplifiers. This configuration yields a 105Ω differential and 150Ω common mode impedance. A fail safe bias of 112mV is maintained when no drivers are connected to the SCSI bus. The SS8218 DIFFB pin monitors the DIFFSENS line to determine the proper operating mode of the device; this mode is indicated by the SE/LVD/HVD outputs. SE mode When the external driver for a given signal line turns off, the active terminator will pull that signal line to 2.85 volts (quiescent state). When used with an active negation driver, the power amp can sink 22mA per line while keeping the voltage reference in regulation. The terminating resistors maintain their 110Ω value. HVD Isolation Mode The SS8218 identifies that there is an HVD (high voltage differential) device on the SCSI bus and isolates the termination pins from the bus. When DISCNCT is pulled high, the termination pins are isolated from the SCSI bus, and the bus mode indicators (SE/LVD/HVD) as well as VREF remains active. During thermal shutdown, the termination pins are isolated from the SCSI bus and VREF becomes high impedance. The DIFFSENSE driver is shut down during either of these two events. To ensure proper operation, the TPWR pin should be connected to the SCSI bus TERMPWR line. As with all analog circuitry, the TERMPWR lines should be bypassed locally. A 2.2µF capacitor and a 0.01µF high frequency capacitor is recommended between TPWR Rev.2.01 6/06/2003 To maintain the specified regulation, a 4.7µF capacitor is required between the VREF pin and ground of each SS8218. A high frequency cap (0.1µF ceramic recommended) can also be placed on the VREF pin in applications that use fast rise/fall time drivers. A typical SCSI bus configuration is shown in Figure2. An internal pull down resistor assures that the SS8218 will be terminating the bus if the DISCNCT pin is left floating. www.SiliconStandard.com 2 of 11 SS8218 Block Diagram (Figure 1) ( 36pin SSOP only ) M/S DIFFSENSE SE LVD HVD DISCNCT THERMAL SHUTDOWN CIRCUITRY DIFFSENSE CIRCUITRY CONTROL LOGIC DIFFB VREF VREF R1- 110 Ohms R9110 Ohms REFERENCE GENERATION + _ VTOP1 RTOP9 X9 RTOP1 R1- R1R9R9- RMID1 RMID9 R1+ R1+ R9+ R9+ RBOT1 + _ RBOT9 VBOT1 X9 SE GND DRIV ER Rev.2.01 6/06/2003 www.SiliconStandard.com 3 of 11 SS8218 SCSI Bus Configuration (Figure 2) CONTROL LINES (9) TERMPWR 2.2µF TERMPWR TPWR M/S DISCNCT TPWR M/S DISCNCT SS8218 SS8218 DIFFSENS DIFFSENSE VREF 20K 20K 2.2µF DIFFSENSE DIFFB VREF DIFFB 4.7µF 0.1µF 0.1µF 4.7µF DATA LINES (9) TPWR TPWR M/S M/S DISCNCT SS8218 DIFFB DIFFB VREF 4.7µF 4.7µF 2.2µF DATA LINES (9) TPWR TPWR M/S M/S DISCNCT VREF 2.2µF DISCNCT SS8218 SS8218 DIFFB DIFFB VREF 4.7µF 4.7µF Rev.2.01 6/06/2003 2.2µF DISCNCT SS8218 VREF 2.2µF www.SiliconStandard.com 4 of 11 SS8218 Recommended Operating Conditions PARAMETER SYMBOL MIN TYP MAX UNITS Vtpwr (SE) Vtpwr (LVD) 4.0 2.9 5 5 5.5 5.5 V Vil Vih Tamb -0.3 2.0 0 +0.8 Vtpwr+0.3 70 V V °C Termpower Voltage Logic 0 Logic 1 Operating Temperature Electrical Characteristics Unless otherwise specified, these specifications apply over the operating ambient temperature range of 0°C≤ ≤TA≤70°C. PARAMETER SYMBOL Condition MIN Rdm 100 105 110 Ohms Rcm Vdm Vcm All lines Open 110 100 1.125 150 112 1.25 190 125 1.375 Ohms mV V 110 2.85 3 115.5 2.93 25.4 pF Ohms Volts mA 2.5 3.5 % % mA LVD Terminator Section Differential Mode Termination Resistance Common Mode Termination Resistance Differential Mode Bias Common Mode Bias Single Ended Terminator Section Output Capacitance SE Termination Resistance SE Voltage Reference SE output Current Cout Rse Vref Iose Regulator Section Line Regulation Load Regulation Current Limit Sink Current Note Vline = 0-3.0 volts 104.5 2.79 TYP Vline = 0.2 volts LIREG LOREG ILIM 1.0 1.3 350 ISINK MAX 200 UNITS mA DC Section Termpower Current Itpmr Input Leakage High Input Leakage Low Output Current High Output Current Low Iih Iil Ioh Iol DIFFSENS Section DIFFSENS SE Operating Range DIFFSENS LVD Operating Range DIFFSENS HVD Operating Range Vseor Vlvdor Vhvdor DIFFSENSE Driver Output Voltage DIFFSENSE Driver Source Current DIFFSENSE Driver Sink Current Vdso Idsh Idsl SE mode (No Load) LVD mode (No Load) 4 20 mA -1.0 1.0 Vout = 2.4 volts;SE/LVD/HVD Pins only Vout=0.4 volts;SE/LVD/HVD Pins only -1.0 4.0 -0.3 0.7 2.4 M/S=1; Ids = 0-5mA M/S = 1; Vdso=0V M/S=1; Vdso=2.75V 1.2 5 20 µA µA mA mA 0.5 1.9 Vtpwr+0.3 V V V 1.4 15 200 V mA µA Note: Guaranteed by Design. Rev.2.01 6/06/2003 www.SiliconStandard.com 5 of 11 SS8218 Common Mode Bias Vcm Temperature Common Mode Bias Vcm - Vtpwr 1.375 1.375 1.325 T=80ºC 1.275 Vcm(V) Vcm(V) 1.325 1.225 T=-10ºC 1.175 Vtpwr=5.8V 1.275 1.225 Vtpwr=2.8V 1.175 1.125 1.125 2.5 3.5 4.5 Vtpwr -20 5.5 0 20 40 60 80 Temperature(℃) 100 Differential Mode Bias Vdm Temperature @Vtpwr=5V Differential Mode Bias Vdm - Vtpwr 0.125 0.125 0.12 0.12 0.115 Vdm(V) Vdm(V) T=-10ºC 0.11 0.115 0.11 T=80ºC 0.105 0.105 0.1 0.1 2.5 3.5 4.5 Vtpwr 5.5 -20 190 180 180 170 170 Rcm(Ohm) Rcm(Ohm) 190 150 140 100 150 140 130 120 120 110 2.5 3.5 4.5 Vtpwr 5.5 -20 Differential Mode Termination Resistance Rdm - Vtpwr 110 110 108 108 106 T=80ºC 104 0 20 40 60 80 Temperature(ºC) 100 Differential Mode Termination Resistance Rdm - Temperature Rdm(Ohm) Rdm(Ohm) 80 160 130 110 Vtpwr=2.8V 106 104 102 102 T=-10ºC 100 2.5 Rev.2.01 6/06/2003 20 40 60 Temperature(ºC) Common Mode Termination Resistance Rcm - Temperature@Vtpwr=5V Common Mode Termination Resistance Rcm - Vtpwr@Temperature=24ºC 160 0 3.5 Vtpwr=5.8V 100 4.5 Vtpwr 5.5 -20 www.SiliconStandard.com 0 20 40 60 Temperature(ºC) 80 100 6 of 11 SS8218 Rse(Ohm) 115 114 113 112 111 110 109 108 107 106 105 Rse(Ohm) 3.5 4.5 Vtpwr 5.5 SE Termination Resistance Rse - Vtpwr @Vtpwr=5V;T=24ºC 115 114 113 112 111 110 109 108 107 106 105 0 1 2 3 Vline SE Termination Resistance Rse - Vtpwr @Vline=0V 115 114 113 Vtpwr=3.8V 112 111 110 109 108 107 Vtpwr=5.8V 106 105 -20 0 20 40 60 80 100 Temperature(ºC) Vref - Ivref@Vtpwr=5V;T=24ºC 2.93 2.91 2.89 Vref Rse(Ohm) SE Termination Resistance Rse - Vtpwr @T=24ºC;Vline=0V 2.87 2.85 2.83 2.81 2.79 -250 -150 Vref - Temperature@Ivref=0mA 2.93 2.91 2.91 250 350 2.89 Vtpwr=5.8V 2.87 Vref Vref 50 150 Ivref(mA) Vref - Vtpwr@T=24ºC 2.93 2.89 2.85 2.83 2.87 Ivref=-200mA 2.85 2.83 2.81 Ivref=350mA 2.81 Vtpwr=3.8V 2.79 2.79 -20 Rev.2.01 6/06/2003 -50 0 20 40 60 Temperature(ºC) 80 100 3.5 www.SiliconStandard.com 4.5 5.5 6.5 Vtpwr 7 of 11 SS8218 Pin Description (for 28pin SSOP/TSSOP) PIN SYMBOL DESCRIPTION 1 VREF* 2-5,7-12, 18-21, 23-26 Rx+, Rx- Reference Voltage. 2.85-volt reference; must be connected to a 4.7µF capacitor. Signal Termination. (X=1,2,3,…..9) Rx+: Ground line for single-ended or positive line for differential applications for the SCSI bus. Rx-: Signal line/active line for single-ended or negative line in differential applications for the SCSI bus. 6,22 13 14 15 16 17 27,28 NC/ HS GND No Connect/ HS GND. Should be grounded for heat sinking purpose. DISCNCT Disconnect. When pulled high, the SS8218 isolates its bus pins (Rx+, Rx-) from the SCSI bus. GND Ground. Terminator ground pin. Connected to ground. Master/slave. Used to select which terminator is the controlling device. M/S pin high enables the M/S DIFFSENSE driver. DIFFSENSE Output to drive the SCSI bus DIFFSENS line. DIFFB pin should be connected to a 0.1µF capacitor to GND and 20k resistor to SCSI/Bus DIFFB DIFFSENS line. An input pin to detect the type of device (differential or single-ended) on the SCSI bus. TPWR Terminator Power. Connect to the SCSI TERMPWR line and de-couple with a 2.2µF capacitor. *The VREF keeps the level at 2.85 volt, despite the DISCNCT pin is asserted or not; even the termination mode is changed. (36pin SSOP) PIN SYMBOL 1 VREF* 2,3 4-7,11-16, 22-25, 29-32 8, 9,10,26, 27,28 17 NC DISCNCT 18 GND 19 20 21 33 34 35 36 Rx+ RxHS/GND DESCRIPTION Reference Voltage. 2.85-volt reference; must be connected to a 4.7µF capacitor. No Connect. Do not connect these pins. Signal Termination. (X=1,2,3,…..9) Rx+: Ground line for single-ended or positive line for differential applications for the SCSI bus. Rx-: Signal line/active line for single-ended or negative line in differential applications for the SCSI bus. Heat Sink Ground. Connect to large area PC board traces to increase power dissipation capability. Disconnect. When pulled high, the SS8218 isolates its bus pins (Rx+, Rx-) from the SCSI bus. Ground. Terminator ground pin. Connected to ground. Master/slave. Used to select which terminator is the controlling device. M/S pin high enables the M/S DIFFSENSE driver. DIFFSENSE Output to drive the SCSI bus DIFFSENS line. DIFFB pin should be connected to a 0.1µF capacitor to GND and 20k resistor to SCSI/Bus DIFFB DIFFSENS line. An input pin to detect the type of device (differential or single-ended) on the SCSI bus. SE LVD HVD TPWR Single ended mode indicator. It is HIGH when terminator is operating in SE mode. Low Voltage Differential mode indicator. It is HIGH when terminator is operating in LVD mode. High Voltage Differential mode indicator. It is HIGH when terminator is operating in HVD mode Terminator Power. Connect to SCSI bus TERMPWR line and decouple with 2.2µF capacitor. *The VREF keeps the level at 2.85 volt, despite the DISCNCT pin is asserted or not; even the termination mode is changed. Rev.2.01 6/06/2003 www.SiliconStandard.com 8 of 11 SS8218 Package Information (28 pin SSOP) 0.25 C D L 28 E1 E 1.00 REF 1 θ A2 A A1 b e Min. Dimension in mm Typ. Max. Min. Dimension in inch Typ. Max. A 1.35 1.60 1.75 0.053 0.064 0.069 A1 A2 b C 0.10 ----0.20 0.19 ----1.45 0.25 ----- 0.25 ----0.30 0.25 0.004 ----0.008 0.007 ----0.057 0.010 ----- 0.010 ----0.012 0.010 D E E1 e 9.80 5.80 3.80 ----- ------------0.64 10.00 6.20 4.00 ----- 0.386 0.228 0.150 ----- ------------0.025 0.394 0.244 0.157 ----- L y θ 0.40 ----0º ------------- 1.27 0.10 8º 0.016 ----0º ------------- 0.050 0.004 8º Symbol Rev.2.01 6/06/2003 www.SiliconStandard.com 9 of 11 SS8218 36 pin SSOP C L E1 E h x 45° θ D A A1 0.004 C SEATING PLANE b e Symbol Min. Dimension in mm Typ. Max. Min. Dimension in inch Typ. Max. A A1 b c 2.413 0.203 0.300 0.127 2.591 0.305 2.794 0.406 0.450 0.254 0.095 0.008 0.012 0.005 0.102 0.012 0.110 0.016 0.018 0.010 D e E E1 15.748 15.875 0.800 BASIC 16.002 0.620 0.625 0.032 BASIC 0.630 10.668 7.595 0.395 0.291 h L θ 0.381 0.508 0 0.635 1.016 8 0.015 0.020 0 10.033 7.391 7.493 0.295 0.420 0.289 0.025 0.040 8 Taping Specification Feed Direction Typical SSOP, TSSOP Package Orientation Rev.2.01 6/06/2003 www.SiliconStandard.com 10 of 11 SS8218 28 pin TSSOP C D 28 L E1 E 1 θ A A2 A1 e b NOTE: 1. Package body sizes exclude mold flash protrusions or gate burrs 2. Tolerance ±0.1mm unless otherwise specified 3. Coplanarity : 0.1mm 4. Controlling dimension is in millimeter. Converted inch dimensions are not necessarily accurate. 5. Follow JEDEC MO-153 MIN. DIMENSION IN MM NOM. MAX. MIN. DIMENSION IN INCH NOM. MAX. A A1 A2 b ----0.05 0.80 0.19 --------1.00 ----- 1.20 0.15 1.05 0.30 ----0.002 0.031 0.007 --------0.039 ----- 0.048 0.006 0.041 0.012 C D E E1 0.09 9.60 ----4.30 ----9.70 6.40 4.40 0.20 9.80 ----4.50 0.004 0.378 ----0.169 ----0.382 0.252 0.173 0.008 0.386 ----0.177 e L y θ ----0.45 ----0º 0.65 0.60 --------- ----0.75 0.10 8º ----0.018 ----0º 0.026 0.024 --------- ----0.030 0.004 8º SYMBOL Information furnished by Silicon Standard Corporation is believed to be accurate and reliable. However, Silicon Standard Corporation makes no guarantee or warranty, express or implied, as to the reliability, accuracy, timeliness or completeness of such information and assumes no responsibility for its use, or for infringement of any patent or other intellectual property rights of third parties that may result from its use. Silicon Standard reserves the right to make changes as it deems necessary to any products described herein for any reason, including without limitation enhancement in reliability, functionality or design. No license is granted, whether expressly or by implication, in relation to the use of any products described herein or to the use of any information provided herein, under any patent or other intellectual property rights of Silicon Standard Corporation or any third parties. Rev.2.01 6/06/2003 www.SiliconStandard.com 11 of 11