G218A Global Mixed-mode Technology Inc. Multi-mode LVD/SE SCSI Terminator Features General Description Auto-selectable multi-mode Single-Ended The G218A Multi-mode LVD/SE SCSI terminator provides a smooth transition into the next generation of the SCSI Parallel Interface (SPI-2). 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 G218A detects a HVD SCSI device, it switches to a high impedance state. For a 16-bit Wide SCSI bus to be operational, three G218A terminators are needed. or LVD Termination Meets SCSI-1, SCSI-2, SCSI-3 SPI Ultra (Fast-20), Ultra 2(SPI-2 LVD), Ultra160 standards. Supports active negation Current limit and thermal protection Hot-Swap compatible (Single-Ended) 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 The Multi-mode terminator contains all functions required to terminate and auto detect and switch modes for SCSI parallel Interface (SPI-2) bus architectures. For the SE termination, one regulator and nine precision 110ohm resistors are used. For the LVD termination, the G218A integrates two regulated supplies with nine precision resistor strings. Applications Server and workstation High-end PC Industrial PC Disk Array (RAID) SCSI cable Pin Configuration (Top View) G218A G218A TPWR VREF NC 1 36 2 35 HVD NC 3 34 LVD R1+ 4 33 SE R1- 5 32 R9- 6 31 R9+ 7 30 R8- VREF 1 28 TPWR R1+ 2 27 R1- 3 26 TPWR R9- R2+ R2- 4 25 R9+ R2+ R2- 5 24 R8- HS/GND 8 29 NC 6 23 R8+ 28 R3+ 7 22 NC HS/GND 9 HS/GND 10 R8+ HS/GND 27 HS/GND R3- 8 21 R7- R3+ 11 26 HS/GND R4+ 9 20 R7+ R3- 12 25 R4- 10 19 R6- R4+ 13 24 R7R7+ R6+ R4- 14 23 R6- R5+ 15 22 R6+ R5- 16 21 DIFFB DISCNCT 17 20 GND 18 19 DIFFSENSE M/S R5+ 11 18 R5- 12 17 DIFFB DISCNCT 13 16 DIFFSENSE GND 14 15 M/S 28Pin SSOP/TSSOP 36Pin SSOP Ver 3.3 Sep 11, 2001 TEL: 886-3-5788833 http://www.gmt.com.tw 1 Global Mixed-mode Technology Inc. G218A Ordering Information PART NUMBER TEMP. RANGE PIN-PACKAGE FEATURE G218AT-S4 G218AR-S4 0ºC-70ºC 0ºC-70ºC SSOP-28 pin / Tube SSOP-28 pin / Tape & Reel DISCNCT does not disable VREF DISCNCT does not disable VREF G218AT-S5 G218AR-S5 G218AT-D3 G218AR-D3 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 Functional Description The DIFFSENSE pin can also drive the SCSI DIFFSENS line (when M/S=1) to determine the SCSI bus operating mode. The G218A switches to the termination mode that is appropriate for the bus based on the value of the DIFFSENS voltage. These modes are: The G218A combines LVD and SE termination with DIFFSENS sourcing and detection. The LVD termination section consists of two 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) 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. DIFFSENSE is used by multi-mode transceiver (LVD/SE) to determine if the device is connected to a single-ended, LVD or HVD SCSI bus. If the voltage on DIFFSENSE 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. 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. The G218A 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. power trace length, thereby resulting in less input capacitance and reflections which can degrade the bus signals. HVD Isolation Mode The G218A identifies that there is an HVD (high voltage differential) device on the SCSI bus and isolates the termination pins from the bus. To maintain the specified regulation, a 4.7µF capacitor is required between the VREF pin and ground of each G218A. 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. When DISCNCT=1, 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. An internal pull down resistor assures that the G218A will be terminating the bus if the DISCNCT pin is left floating. To ensure proper operation, the TPWR pin should be connected to the SCSI bus TERMPWR line. As with all analog circuitry, the TERMPWR and VDD lines should be bypassed locally. A 2.2µF capacitor and a 0.01µF high frequency capacitor is recommended between TPWR and ground and placed as close as possible to the G218A. The G218A should be placed as close as possible to the SCSI connector to minimize signal and Note: DIFFSENSRefers to the SCSI bus signal. DIFFSENSERefers to the G218A pin name and internal circuitry relating to differential sensing. DIFFBRefers to the G218A pin name and internal circuitry relating to monitoring the DIFFSENS line. Ver 3.3 Sep 11, 2001 TEL: 886-3-5788833 http://www.gmt.com.tw 2 G218A Global Mixed-mode Technology Inc. G218A Block Diagram (Figure 1) ( 36pin SSOP only ) DIFFSENSE DISCNCT M/S SE LVD HVD THERMAL SHUTDOWN CIRCUITRY SE LVD HVD DIFFSENSE CIRCUITRY DIFFB CONTROL LOGIC VREF VREF + _ R1- 110 Ohms R9110 Ohms BANDGAP REFERENCE + _ VTOP RTOP R1- R1R9R9- RMID R1+ R1+ R9+ R9+ RBOT + _ VBOT SE GND DRIVER Ver 3.3 Sep 11, 2001 TEL: 886-3-5788833 http://www.gmt.com.tw 3 G218A Global Mixed-mode Technology Inc. SCSI Bus Configuration (Figure 2) CONTROL LINES (9) TERMPWR 2.2µF TERMPWR TPWR M/S DISCNCT TPWR M/S DISCNCT G218A G218A DIFFSENS DIFFSENSE VREF 20K 20K 2.2µF DIFFSENSE DIFFB VREF DIFFB 0.1µF 0.1µF 4.7µF 4.7µF DATA LINES (9) TPWR TPWR M/S M/S DISCNCT G218A DIFFB DIFFB VREF 4.7µF 4.7µF 2.2µF 2.2µF DISCNCT G218A VREF 2.2µF DATA LINES (9) TPWR TPWR M/S DISCNCT M/S DISCNCT G218A VREF 2.2µF G218A DIFFB DIFFB VREF 4.7µF 4.7µF Ver 3.3 Sep 11, 2001 TEL: 886-3-5788833 http://www.gmt.com.tw 4 Global Mixed-mode Technology Inc. Pin Description G218A (for 28pin SSOP) PIN SYMBOL DESCRIPTION 1 VREF* 2-5,7-12, 18-21, 23-26 Rx+, Rx- Reference Voltage. 2.85-volt reference; a regulator bypass, 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 NC DISCNCT GND 15 M/S 16 17 27,28 No Connect. Do not connect these pins. Disconnect. When pulled high, the G218 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 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 Rx+ RxHS/GND DESCRIPTION Reference Voltage. 2.85-volt reference; a regulator bypass, 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 G218 isolates its bus pins (Rx+, Rx-) from the SCSI bus. Ground. Terminator ground pin. Connected to ground. Master/slave. Mode select for the non controlling terminator. M/S MSTR enables the 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. 33 34 SE LVD 35 HVD 36 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 or thermal shutdown. 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. Ver 3.3 Sep 11, 2001 TEL: 886-3-5788833 http://www.gmt.com.tw 5 G218A Global Mixed-mode Technology Inc. Recommended Operating Conditions SYMBOL MIN TYP MAX UNITS Termpower Voltage PARAMETER Vtpwr 4.5 5 5.50 V Logic 0 Logic 1 Operating Temperature Vil Vih Tamb -0.3 2.0 0 +0.8 Vtpwr+0.3 70 V V °C NOTES (0°C to 70°C) Single Ended Characteristics SYMBOL MIN TYP MAX UNITS NOTES SE Termination Resistance PARAMETER Rse 104.5 110 115.5 Ohms Vline = 0-3.0 volts SE Voltage Reference SE output Current Vref Iose 2.79 2.85 2.93 25.4 Volts mA Vline = 0.2 volts (0°C to 70°C) Low Voltage Differential Characteristics PARAMETER SYMBOL MIN TYP MAX UNITS Differential Mode Termination Resistance Common Mode Termination Resistance Rdm Rcm 100 110 105 150 110 190 Ohms Ohms Differential Mode Bias Common Mode Bias Vdm Vcm 100 1.125 112 1.25 125 1.375 mV V All lines Open (0°C to 70°C) DC Characteristics PARAMETER SYMBOL MIN Termpower Current Input Leakage High Itpmr Iih -1.0 Input Leakage Low Output Current High Output Current Low DIFFSENS SE Operating Range Iil Ioh Iol Vseor -1.0 4.0 -0.3 DIFFSENS LVD Operating Range DIFFSENS HVD Operating Range DIFFSINS Driver Output Voltage DIFFSENSE Driver Source Current Vlvdor Vhvdor Vdso Idsh 0.7 2.4 1.2 Idsl 20 DIFFSENSE Driver Sink Current TYP MAX 35 1.0 5 UNITS NOTES mA µA All lines Open 0.5 µA mA mA V 1.9 Vtpwr+0.3 1.4 15 V V V mA M/S=1; Ids = 0-5mA M/S = 1; Vdso=0V 200 µA M/S=1; Vdso=2.75V Vout = 2.4 volts;SE/LVD/HVD Pins only Vout=0.4 volts;SE/LVD/HVD Pins only (0°C to 70°C) Regulator Characteristics PARAMETER Line Regulation Load Regulation Current Limit Sink Current NOTES SYMBOL MIN LIREG LOREG ILIM ISINK 200 TYP MAX UNITS 1.0 1.3 350 2.0 3.0 % % mA NOTES mA Ver 3.3 Sep 11, 2001 TEL: 886-3-5788833 http://www.gmt.com.tw 6 G218A Global Mixed-mode Technology Inc. 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. 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 Ver 3.3 Sep 11, 2001 Max. TEL: 886-3-5788833 http://www.gmt.com.tw 7 G218A Global Mixed-mode Technology Inc. 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 Ver 3.3 Sep 11, 2001 0.295 0.420 0.289 0.025 0.040 8 TEL: 886-3-5788833 http://www.gmt.com.tw 8 G218A Global Mixed-mode Technology Inc. 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 millimeter converted inch dimensions are not necessarily exact. 5. Followed from JEDEC MO-153 SYMBOL MIN. DIMENSION IN MM NOM. MAX. MIN. DIMENSION IN INCH NOM. MAX. A ----- ----- 1.20 ----- ----- 0.048 A1 A2 b C 0.05 0.80 0.19 0.09 ----1.00 --------- 0.15 1.05 0.30 0.20 0.002 0.031 0.007 0.004 ----0.039 --------- 0.006 0.041 0.012 0.008 D E E1 e 9.60 ----4.30 ----- 9.70 6.40 4.40 0.65 9.80 ----4.50 ----- 0.378 ----0.169 ----- 0.382 0.252 0.173 0.026 0.386 ----0.177 ----- L y θ 0.45 ----0º 0.60 --------- 0.75 0.10 8º 0.018 ----0º 0.024 --------- 0.030 0.004 8º Taping Specification Feed Direction Typical SSOP, TSSOP Package Orientation Ver 3.3 Sep 11, 2001 TEL: 886-3-5788833 http://www.gmt.com.tw 9