View G218AT-S5_1243778.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

Global Mixed-mode Technology Inc.
G218A
Multi-mode LVD/SE SCSI Terminator
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 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
General Description
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. 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
VREF R1+ R1R2+ R2NC R3+ R3R4+ R4R5+ R5DISCNCT GND 1 2 3 4 5 6 7 8 9 10 11 12 13 14 28 27 26 25 24 23 22 21 20 19 18 17 16 15 TPWR TPWR R9R9+ R8R8+ NC R7R7+ R6R6+ DIFFB DIFFSENSE M/S
VREF NC NC R1+ R1R2+ R2HS/GND
1 2 3 4 5 6 7 8
36 35 34 33 32 31 30 29 28 27 26 25 24 23 22 21 20 19
TPWR HVD LVD SE R9R9+ R8R8+ HS/GND HS/GND HS/GND R7R7+ R6R6+ DIFFB DIFFSENSE M/S
HS/GND 9 HS/GND 10 R3+ R3R4+ R4R5+ R5DISCNCT 11 12 13 14 15 16 17
GND 18
28Pin SSOP/TSSOP
Ver 3.3 Sep 11, 2001
36Pin SSOP
TEL: 886-3-5788833 http://www.gmt.com.tw
1
Global Mixed-mode Technology Inc.
Ordering Information
PART NUMBER
G218AT-S4 G218AR-S4 G218AT-S5 G218AR-S5 G218AT-D3 G218AR-D3
G218A
FEATURE
DISCNCT does not disable VREF DISCNCT does not disable VREF DISCNCT does not disable VREF DISCNCT does not disable VREF DISCNCT does not disable VREF DISCNCT does not disable VREF
TEMP. RANGE
0C-70C 0C-70C 0C-70C 0C-70C 0C-70C 0C-70C
PIN-PACKAGE
SSOP-28 pin / Tube SSOP-28 pin / Tape & Reel SSOP-36 pin / Tube SSOP-36 pin / Tape & Reel TSSOP-28 pin / Tube TSSOP-28 pin / Tape & Reel
Functional Description
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) 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. 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. 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. 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. 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 2.2F capacitor and a 0.01F 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
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: LVD mode LVD termination is provided by a precision resistor string with two amplifiers. This configuration yields a 105 differential and 150 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 regulation. The terminating resistors maintain their 110 value. power trace length, thereby resulting in less input capacitance and reflections which can degrade the bus signals. To maintain the specified regulation, a 4.7F capacitor is required between the VREF pin and ground of each G218A. A high frequency cap (0.1F 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 G218A will be terminating the bus if the DISCNCT pin is left floating. 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
Global Mixed-mode Technology Inc.
G218A Block Diagram
(Figure 1)
G218A
( 36pin SSOP only ) DIFFSENSE SE LVD HVD DISCNCT M/S
THERMAL SHUTDOWN CIRCUITRY
DIFFB
DIFFSENSE CIRCUITRY
SE LVD HVD
CONTROL LOGIC
VREF + _ VREF 110 Ohms R1-
R9110 Ohms
BANDGAP REFERENCE
+ _
VTOP
RTOP R1R1R9R9RMID 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
Global Mixed-mode Technology Inc.
SCSI Bus Configuration (Figure 2)
G218A
TERMPWR 2.2F TPWR M/S DISCNCT
CONTROL LINES (9) TPWR M/S DISCNCT
TERMPWR 2.2F
G218A
G218A
DIFFSENSE VREF DIFFB 20K 4.7F 0.1F
DIFFSENS
DIFFSENSE DIFFB VREF 20K 0.1F 4.7F
2.2F
TPWR M/S DISCNCT
DATA LINES (9)
TPWR M/S DISCNCT
2.2F
G218A
G218A
VREF
DIFFB
DIFFB
VREF
4.7F 2.2F TPWR M/S DISCNCT DATA LINES (9)
4.7F TPWR M/S DISCNCT 2.2F
G218A
G218A
VREF
DIFFB
DIFFB
VREF
4.7F
4.7F
Ver 3.3 Sep 11, 2001
TEL: 886-3-5788833 http://www.gmt.com.tw
4
Global Mixed-mode Technology Inc.
Pin Description
PIN
1 2-5,7-12, 18-21, 23-26 6,22 13 14 15 16 17 27,28 VREF*
G218A
(for 28pin SSOP) DESCRIPTION
Reference Voltage. 2.85-volt reference; a regulator bypass, must be connected to a 4.7F 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. 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.
SYMBOL
Rx+, Rx-
NC DISCNCT GND M/S
DIFFSENSE Output to drive the SCSI bus DIFFSENS line. DIFFB pin should be connected to a 0.1F 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 2.2F 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
1 2,3 4-7,11-16, 22-25, 29-32 8, 9,10,26, 27,28 17 18 19 20 21 33 34 35 36
SYMBOL
VREF* NC Rx+ RxHS/GND DISCNCT GND
DESCRIPTION
Reference Voltage. 2.85-volt reference; a regulator bypass, must be connected to a 4.7F 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 0.1F 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 or thermal shutdown. Terminator Power. Connect to SCSI bus TERMPWR line and decouple with 2.2F 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
Global Mixed-mode Technology Inc.
Recommended Operating Conditions PARAMETER
Termpower Voltage Logic 0 Logic 1 Operating Temperature
G218A
MAX
5.50 +0.8 Vtpwr+0.3 70
SYMBOL
Vtpwr Vil Vih Tamb
MIN
4.5 -0.3 2.0 0
TYP
5
UNITS
V V V C
NOTES
Single Ended Characteristics PARAMETER
SE Termination Resistance SE Voltage Reference SE output Current
(0C to 70C) SYMBOL
Rse Vref Iose
MIN
104.5 2.79
TYP
110 2.85
MAX
115.5 2.93 25.4
UNITS
Ohms Volts mA
NOTES
Vline = 0-3.0 volts Vline = 0.2 volts
Low Voltage Differential Characteristics PARAMETER
Differential Mode Termination Resistance Common Mode Termination Resistance Differential Mode Bias Common Mode Bias
(0C to 70C) MIN
100 110 100 1.125
SYMBOL
Rdm Rcm Vdm Vcm
TYP
105 150 112 1.25
MAX
110 190 125 1.375
UNITS
Ohms Ohms mV V
NOTES
All lines Open
DC Characteristics PARAMETER
Termpower Current Input Leakage High Input Leakage Low Output Current High Output Current Low DIFFSENS SE Operating Range DIFFSENS LVD Operating Range DIFFSENS HVD Operating Range DIFFSINS Driver Output Voltage DIFFSENSE Driver Source Current DIFFSENSE Driver Sink Current
(0C to 70C) SYMBOL
Itpmr Iih Iil Ioh Iol Vseor Vlvdor Vhvdor Vdso Idsh Idsl
MIN
-1.0
TYP
35
MAX
UNITS
mA A
NOTES
All lines Open
1.0 -1.0 4.0 -0.3 0.7 2.4 1.2 5 20
0.5 1.9 Vtpwr+0.3 1.4 15 200
A mA mA V V V V mA A
Vout = 2.4 volts;SE/LVD/HVD Pins only Vout=0.4 volts;SE/LVD/HVD Pins only
M/S=1; Ids = 0-5mA M/S = 1; Vdso=0V M/S=1; Vdso=2.75V
Regulator Characteristics PARAMETER
Line Regulation Load Regulation Current Limit Sink Current
(0C to 70C) SYMBOL
LIREG LOREG ILIM ISINK 200
MIN
TYP
1.0 1.3 350
MAX
2.0 3.0
UNITS
% % mA mA
NOTES
Ver 3.3 Sep 11, 2001
TEL: 886-3-5788833 http://www.gmt.com.tw
6
Global Mixed-mode Technology Inc.
Package Information (28 pin SSOP)
0.25
G218A
C
D 28
L
E1
E
1.00 REF
1
A2 A1 b e
A
Symbol
A A1 A2 b C D E E1 e L y
Min.
1.35 0.10 ----0.20 0.19 9.80 5.80 3.80 ----0.40 ----0
Dimension in mm Typ.
1.60 ----1.45 0.25 ----------------0.64 -------------
Max.
1.75 0.25 ----0.30 0.25 10.00 6.20 4.00 ----1.27 0.10 8
Min.
0.053 0.004 ----0.008 0.007 0.386 0.228 0.150 ----0.016 ----0
Dimension in inch Typ.
0.064 ----0.057 0.010 ----------------0.025 -------------
Max.
0.069 0.010 ----0.012 0.010 0.394 0.244 0.157 ----0.050 0.004 8
Ver 3.3 Sep 11, 2001
TEL: 886-3-5788833 http://www.gmt.com.tw
7
Global Mixed-mode Technology Inc.
36 pin SSOP
C
G218A
L
E1 E
h x 45
D
A 0.004 C SEATING PLANE e b A1
Symbol
A A1 b c D e E E1 h L
Min.
2.413 0.203 0.300 0.127 15.748 10.033 7.391 0.381 0.508 0
Dimension in mm Typ.
2.591 0.305
Max.
2.794 0.406 0.450 0.254 16.002 10.668 7.595 0.635 1.016 8
Min.
0.095 0.008 0.012 0.005 0.620 0.395 0.291 0.015 0.020 0
Dimension in inch Typ.
0.102 0.012
Max.
0.110 0.016 0.018 0.010 0.630 0.420 0.289 0.025 0.040 8
15.875 0.800 BASIC 7.493
0.625 0.032 BASIC 0.295
Ver 3.3 Sep 11, 2001
TEL: 886-3-5788833 http://www.gmt.com.tw
8
Global Mixed-mode Technology Inc.
28 pin TSSOP
D 28
C
G218A
L
E1
E
1
A2 A1 e b
A
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
A A1 A2 b C D E E1 e L y
MIN.
----0.05 0.80 0.19 0.09 9.60 ----4.30 ----0.45 ----0
DIMENSION IN MM NOM.
--------1.00 --------9.70 6.40 4.40 0.65 0.60 ---------
MAX.
1.20 0.15 1.05 0.30 0.20 9.80 ----4.50 ----0.75 0.10 8
MIN.
----0.002 0.031 0.007 0.004 0.378 ----0.169 ----0.018 ----0
DIMENSION IN INCH NOM.
--------0.039 --------0.382 0.252 0.173 0.026 0.024 ---------
MAX.
0.048 0.006 0.041 0.012 0.008 0.386 ----0.177 ----0.030 0.004 8
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

▲Up To Search▲

Price & Availability of G218AT-S5

	To Download G218AT-S5 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .