G220 GMT | Alldatasheet

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Technical content

Features

„Auto-selectable multi-mode Single-Ended or LVD Termination „Meets SCSI-1, SCSI-2, SCSI-3 SPI Ultra (Fast-20), Ultra 2(SPI-2 LVD), Ultra160 (SPI-3 LVD), and Ultra320 (SPI-4 LVD) standards „Supports active negation „3pF channel capacitance „2.9V to 5.5V operation „Thermal protection „Hot-Swap compatible „5% tolerance on SE and LVD termination resistance „SE/LVD mode indicators „28 pin TSSOP package

Applications

„Server and workstation „High-end PC „Industrial PC „Disk Array (RAID) „SCSI cable General Description The G220 Multi-mode LVD/SE SCSI terminator pro- vides a smooth transition into the next generation of the SCSI Parallel Interface (SPI-4). It automatically senses the bus, via DIFFSENS, and switches the ter- mination to either single-ended (SE) or low voltage differential (LVD) SCSI, dependent on which type of devices are connected to the bus. If the G220 detects a HVD SCSI device, it switches to a high impedance state. For a 16-bit Wide SCSI bus to be operational, three G220 terminators are needed. The Multi-mode terminator contains all functions re- quired 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 G220 integrates 18 regulated supplies with nine precision resistor strings.

Ordering Information

NUMBER MARKING TEMP. RANGE PACKAGE G220D3X G220 0 °C to +70°C TSSOP-28L Note: X Specify the packing type U: Tape & Reel T: Tube Pin Configuration R1- R1+ R2- NC/ HS GND R3+ R3- R4+ R4- R5+ R5- DISCNCT GND TPWR R9- R9+ R8+ R8- R7- R6- R6+ DIFFB DIFFSENSE M/S TSSOP-28L VREF R2+ LVD R7+ G220 SER1- R1+ R2- NC/ HS GND R3+ R3- R4+ R4- R5+ R5- DISCNCT GND TPWR R9- R9+ R8+ R8- R7- R6- R6+ DIFFB DIFFSENSE M/S TSSOP-28L VREF R2+ LVD R7+ G220 SE

Ver: 0.1 Preliminary Apr 03, 2003 TEL: 886-3-5788833 http://www.gmt.com.tw G220 Global Mixed-mode Technology Inc.

Description

The G220 is used in multi-mode active termination applications, where single ended (SE) and low voltage differential (LVD) devices might coexist. The LVD ter- mination section consists of 18 source/sink amplifiers (VTOP, VBOT), biasing circuitry and nine precision resistor strings (RTOP, RMID, RBOT). The SE termi- nation section consists of a 2.85V source/sink regula- tor with 9 precision 110ohm resistor. The DIFFSENSE section consists of a 1.3V, 5mA driver and a sensing circuit (Figure 1) 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. The G220 DIFFB pin monitors the DIFFSENS line to determine the proper operating mode of the device. HVD Isolation Mode The G220 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 VREF is grounded. During thermal shutdown, the termination pins are isolated from the SCSI bus and VREF is grounded. 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 by- passed 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 G220. The G220 should be placed as close as possi- ble to the SCSI connector to minimize signal and power trace length, thereby resulting in less input ca- pacitance 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 G220 switches to the termi- nation mode that is appropriate for the bus based on the value of the DIFFSENS voltage. These modes are: LVD mode LVD termination is provided by a precision resistor string with two amplifiers. This configuration yields a 105 Ω differential and 150 Ω common mode impedance. A fail safe bias of 112mV is maintained when no drivers are connected to the SCSI bus. 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 regula- tion. The terminating resistors maintain their 110 Ω value. To maintain the specified regulation, a 4.7µF capacitor is required between the VREF pin and ground of each G220. A high frequency cap (0.1µF ceramic recom- mended) can also be placed on the VREF pin in ap- plications that use fast rise/fall time drivers. A typical SCSI bus configuration is shown in Figure2. An internal pull down resistor assures that the G220 will be terminating the bus if the DISCNCT pin is left floating. DIFFSENS noise filtering The G220 incorporates a internal digital filter to re- move the noise signal on the DIFFSENS control line, thereby eliminating erroneous switching between modes. The external filter may be used in addition to the internal digital filter.

Ver: 0.1 Preliminary Apr 03, 2003 TEL: 886-3-5788833 http://www.gmt.com.tw G220 Global Mixed-mode Technology Inc. Block Diagram (Figure 1) DIFFB DIFFSENSE SE LVD THERMAL SHUTDOWN CIRCUITRY DISCNCT CONTROL LOGIC VREF DIFFSENSE CIRCUITRY REFERENCE GENERATION VREF

110 Ohms

Ver: 0.1 Preliminary Apr 03, 2003 TEL: 886-3-5788833 http://www.gmt.com.tw G220 Global Mixed-mode Technology Inc. SCSI Bus Configuration (Figure 2) G220 G220 G220 G220 TPWR M/S DISCNCT DIFFSENSE CONTROL LINES (9) DIFFSENS TPWR TERMPWR 20K VREF DIFFB 0.1µF DIFFSENSE DIFFB VREF TERMPWR TPWR M/S DISCNCT DIFFB VREF TPWR DIFFB VREF TPWR DATA LINES (9) VREF DIFFB TPWR VREF DIFFB DATA LINES (9) G220G220 2.2µF 2.2µF 2.2µF 2.2µF 2.2µF 2.2µF M/S DISCNCT M/S DISCNCT M/S DISCNCT M/S DISCNCT 4.7µF 4.7µF 4.7µF 4.7µF 4.7µF 4.7µF 0.1µF 20K G220 G220 G220 G220 TPWR M/S DISCNCT DIFFSENSE CONTROL LINES (9) DIFFSENS TPWR TERMPWR 20K VREF DIFFB 0.1µF DIFFSENSE DIFFB VREF TERMPWR TPWR M/S DISCNCT DIFFB VREF TPWR DIFFB VREF TPWR DATA LINES (9) VREF DIFFB TPWR VREF DIFFB DATA LINES (9) G220G220 2.2µF 2.2µF 2.2µF 2.2µF 2.2µF 2.2µF M/S DISCNCT M/S DISCNCT M/S DISCNCT M/S DISCNCT 4.7µF 4.7µF 4.7µF 4.7µF 4.7µF 4.7µF 0.1µF 20K

Ver: 0.1 Preliminary Apr 03, 2003 TEL: 886-3-5788833 http://www.gmt.com.tw G220 Global Mixed-mode Technology Inc. Recommended Operating Conditions PARAMETER SYMBOL MIN TYP MAX UNITS Vtpwr(SE) 4.0 5 5.5 Termpower Voltage Vtpwr(LVD) 2.9 5 5.5 V Logic 0 V il -0.3 +0.8 V Logic 1 V ih 2.0 V tpwr+0.3 V Operating Temperature T amb 0 70 °C

Electrical Characteristics

Unless otherwise specified, these specifications apply over the operating ambient temperature range of PARAMETER SYMBOL CONDITION MIN TYP MAX UNITS LVD Terminator Section Differential Mode Termination Resistance Rdm 100 105 110 Ohms Common Mode Termination Resistance Rcm 110 150 190 Ohms Differential Mode Bias Vdm All lines Open 100 112 125 mV Common Mode Bias Vcm 1.125 1.25 1.375 V Single Ended Terminator Section Output Capacitance Cout Note 3 pF SE Termination Resistance Rse Vline = 0-3.0 volts 104.5 110 115.5 Ohms SE Voltage Reference Vref 2.79 2.85 2.93 Volts SE output Current Iose Vline = 0.2 volts 25.4 mA Regulator Section Line Regulation LI REG 1.0 2.5 % Load Regulation LO REG 1.3 3.5 % Current Limit I LIM 350 mA Sink Current I SINK 200 mA DC Section SE mode (No Load) 4 Termpower Current I tpmr LVD mode (No Load) 20 mA Input Leakage High I ih -1.0 µA Input Leakage Low I il 1.0 µA Output Current High I oh V out = 2.4 volts; SE/LVD Pins only -1.0 mA Output Current Low I ol V out=0.4 volts; SE/LVD Pins only 4.0 mA DIFFSENS Section DIFFSENS SE Operating Range V seor -0.3 0.5 V DIFFSENS LVD Operating Range V lvdor 0.7 1.9 V DIFFSENS HVD Operating Range V hvdor 2.4 V tpwr+0.3 V DIFFSENSE Driver Output Voltage V dso M/S=1; I ds = 0-5mA 1.2 1.4 V DIFFSENSE Driver Source Current I dsh M/S = 1; V dso=0V 5 15 mA DIFFSENSE Driver Sink Current I dsl M/S=1; V dso=2.75V 20 200 µA Note: Guaranteed by Design.

Ver: 0.1 Preliminary Apr 03, 2003 TEL: 886-3-5788833 http://www.gmt.com.tw G220 Global Mixed-mode Technology Inc. Typical Operating Characteristics Common Mode Bias Vcm - Temperature 1.125 1.175 1.225 1.275 1.325 1.375 -20 0 20 40 60 80 100 Temperature(ºC) Vcm(V) Vtpwr=2.8V Vtpwr=5.8V Common Mode Bias Vcm - Vtpwr 1.125 1.175 1.225 1.275 1.325 1.375 2.5 3.5 4.5 5.5 Vtpwr Vcm(V) T=80ºC T=-10ºC Common Mode Termination Resistance Rcm - Vtpwr @Temperature=24ºC 110 120 130 140 150 160 170 180 190 2.5 3.5 4.5 5.5 Vtpwr Rcm(Ohm) Common Mode Termination Resistance Rcm - Temperature@Vtpwr=5V 110 120 130 140 150 160 170 180 190 -20 0 20 40 60 80 100 Temperature(ºC) Rcm(Ohm) Differential Mode Termination Resistance Rdm - Vtpwr 100 101 102 103 104 105 106 107 108 109 110 2.5 3.5 4.5 5.5 Vtpwr Rdm(Ohm) T=80ºC T=-10ºC Differential Mode Termination Resistance Rdm - Temperature 100 102 104 106 108 110 -20 0 20 40 60 80 100 Temperature(ºC) Rdm(Ohm) Vtpwr=2.8V Vtpwr=5.8V Differential Mode Bias Vdm - Temperature@Vtpwr=5V 0.1 0.105 0.11 0.115 0.12 0.125 -20 0 20 40 60 80 100 Temperature(ºC) Vdm(V) Differential Mode Bias Vdm - Vtpwr 0.1 0.105 0.11 0.115 0.12 0.125 2.5 3.5 4.5 5.5 Vtpwr Vdm(V) T=-10ºC T=80ºC

Ver: 0.1 Preliminary Apr 03, 2003 TEL: 886-3-5788833 http://www.gmt.com.tw G220 Global Mixed-mode Technology Inc. SE Termination Resistance Rse - Vtpwr @T=24ºC;Vline=0V 105 107 109 111 113 115 3.5 4.5 5.5 Vtpwr Rse(Ohm) SE Termination Resistance Rse - Vtpwr @Vline=0V 105 106 107 108 109 110 111 112 113 114 115 -20 0 20 40 60 80 100 Temperature(ºC) Rse(Ohm) SE Termination Resistance Rse - Vtpwr @Vtpwr=5V;T=24ºC 105 107 109 111 113 115 0123 Vline Rse(Ohm) Vref - Ivref@Vtpwr=5V 2.79 2.81 2.83 2.85 2.87 2.89 2.91 2.93 -250 -150 -50 50 150 250 350 Ivref(mA) Vref T=80ºC T=-10ºC Vref - Temperature@Ivref=0mA 2.79 2.81 2.83 2.85 2.87 2.89 2.91 2.93 -20 0 20 40 60 80 100 Temperature(ºC) Vref Vtpwr=5.8V Vtpwr=3.8V Vref - Vtpwr@T=24ºC 2.79 2.81 2.83 2.85 2.87 2.89 2.91 2.93 3.5 4.5 5.5 Vtpwr Vref Ivref=360mA Ivref=-200mA Ivref=0mA Vtpwr=3.8V Vtpwr=5.8V

Ver: 0.1 Preliminary Apr 03, 2003 TEL: 886-3-5788833 http://www.gmt.com.tw G220 Global Mixed-mode Technology Inc. Pin Description PIN SYMBOL DESCRIPTION 1 VREF Reference Voltage. 2.85-volt reference in SE mode and 1.25V in LVD mode; must be connected to a 4.7µF capacitor. 2-5,7-12, 18-25 Rx+, Rx- 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 NC/ HS GND No Connect/Heat Sink Ground. Should be grounded for heat sinking purpose 13 DISCNCT Disconnect. When pulled high, the G220 isolates its bus pins (Rx+, Rx-) from the SCSI bus. 14 GND Ground. Terminator ground pin. Connected to ground. 15 M/S Master/slave. Used to select which terminator is the controlling device. M/S pin high enables the DIFFSENSE driver. 16 DIFFSENSE Output to drive the SCSI bus DIFFSENS line.

17 DIFFB

DIFFB pin should be connected to a 0.1µF capacitor to GND and 20k resistor to SCSI/Bus DIFFSENS line. An input pin to detect the type of device (differential or single-ended) on the SCSI bus. 26 SE Single ended mode indicator. It is HIGH when terminator is operating in SE mode. 27 LVD Low Voltage Differential mode indicator. It is HIGH when terminator is operating in LVD mode. 28 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.

Ver: 0.1 Preliminary Apr 03, 2003 TEL: 886-3-5788833 http://www.gmt.com.tw G220 Global Mixed-mode Technology Inc.

Package Information

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 DIMENSION IN MM DIMENSION IN INCH Taping Specification GMT Inc. does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and GMT Inc. reserves the right at any time without notice to change said circuitry and specifications. Feed Direction Typical TSSOP Package Orientation Feed Direction Typical TSSOP Package Orientation E1 E D b A C L θ e E1 E D b A C L θ e