ETC G218B

G218B
Global Mixed-mode Technology Inc.
Ultra160 Multi-mode LVD/SE SCSI Terminator
Features
General Description
„Auto-selectable multi-mode Single-Ended
The G218B Multi-mode LVD/SE SCSI terminator provides a smooth transition into 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 G218B detects a HVD SCSI device, it switches to a high impedance state. For a 16-bit Wide SCSI bus to be operational, three G218B 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
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 G218B integrates 18 regulated supplies with nine
precision resistor strings.
Applications
„Server and workstation
„High-end PC
„Industrial PC
„Disk Array (RAID)
„SCSI cable
Pin Configuration
G218B
G218B
VREF
1
28
TPWR
R1+
2
27
VREF
1
36
NC
2
35
HVD
NC
3
34
LVD
TPWR
R1-
3
26
TPWR
R9-
R1+
4
33
4
25
SE
R2+
R2-
R9+
R1-
5
32
R9-
5
24
R8-
23
R9+
6
R8+
6
31
NC/HS GND
R2+
R2-
30
R3+
7
R8-
7
22
NC/HS GND
HS/GND
8
29
HS/GND
9
28
R8+
HS/GND
10
27
HS/GND
11
26
HS/GND
25
R7R7+
R3-
8
21
R7-
R4+
9
20
R7+
R4-
10
19
R6-
HS/GND
R3+
R5+
11
18
R6+
R3-
12
R5-
12
17
DIFFB
R4+
13
24
DISCNCT
13
16
DIFFSENSE
R4-
14
23
R6-
GND
14
15
M/S
R5+
15
22
R6+
R5-
16
21
DIFFB
DISCNCT
17
20
DIFFSENSE
GND
18
19
M/S
28Pin SSOP/TSSOP
36Pin SSOP
Ver 1.3
Jul 19, 2002
TEL: 886-3-5788833
http://www.gmt.com.tw
1
Global Mixed-mode Technology Inc.
Ordering Information
PART NUMBER
TEMP. RANGE
PIN-PACKAGE
G218B
FEATURE
G218BT-S4
G218BR-S4
0ºC-70ºC
0ºC-70ºC
SSOP-28 pin / Tube
SSOP-28 pin / Tape & Reel
DISCNCT does not disable VREF
DISCNCT does not disable VREF
G218BT-S5
G218BR-S5
G218BT-D3
G218BR-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
Note:
DIFFSENSRefers to the SCSI bus signal.
DIFFSENSERefers to the G218B pin name and internal circuitry relating to differential sensing.
DIFFBRefers to the G218B pin name and internal circuitry relating to monitoring the DIFFSENS line.
Functional Description
and ground and placed as close as possible to the
G218B. The G218B 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 G218B 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)
The DIFFSENSE pin can drive the SCSI DIFFSENS
line (when M/S is pulled high) to determine the SCSI
bus operating mode. The G218B 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 G218B 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 G218B 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
G218B. 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 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.
An internal pull down resistor assures that the G218B
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 lines should be bypassed locally. A 2.2µF capacitor and a 0.01µF high
frequency capacitor is recommended between TPWR
Ver 1.3
Jul 19, 2002
TEL: 886-3-5788833
http://www.gmt.com.tw
2
G218B
Global Mixed-mode Technology Inc.
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+
RBOT1
+
_
R9+
RBOT9
VBOT1
X9
SE
GND
DRIV ER
Ver 1.3
Jul 19, 2002
TEL: 886-3-5788833
http://www.gmt.com.tw
3
G218B
Global Mixed-mode Technology Inc.
SCSI Bus Configuration (Figure 2)
TERMPWR
2.2µF
CONTROL LINES (9)
TERMPWR
TPWR
M/S
DISCNCT
TPWR
M/S
DISCNCT
G218B
G218B
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
G218B
DIFFB
DIFFB
VREF
4.7µF
4.7µF
2.2µF
2.2µF
DISCNCT
G218B
VREF
2.2µF
DATA LINES (9)
TPWR
TPWR
M/S
M/S
DISCNCT
DISCNCT
G218B
VREF
2.2µF
G218B
DIFFB
DIFFB
VREF
4.7µF
4.7µF
Ver 1.3
Jul 19, 2002
TEL: 886-3-5788833
http://www.gmt.com.tw
4
G218B
Global Mixed-mode Technology Inc.
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
104.5
2.79
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
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.
Ver 1.3
Jul 19, 2002
TEL: 886-3-5788833
http://www.gmt.com.tw
5
G218B
Global Mixed-mode Technology Inc.
Typical Operating Characteristics
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
T=80ºC
0.105
0.1
2.5
3.5
4.5
Vtpwr
5.5
-20
0
20
40
60
Temperature(ºC)
80
100
Common Mode Termination Resistance
Rcm - Temperature@Vtpwr=5V
Common Mode Termination Resistance
Rcm - Vtpwr@Temperature=24ºC
190
190
180
180
170
170
160
160
Rcm(Ohm)
Rcm(Ohm)
0.11
0.105
0.1
150
140
150
140
130
130
120
120
110
110
2.5
3.5
4.5
Vtpwr
5.5
-20
Differential Mode Termination
Resistance Rdm - Vtpwr
110
110
108
108
106
0
20
40
60
80
Temperature(ºC)
100
Differential Mode Termination Resistance
Rdm - Temperature
Rdm(Ohm)
Rdm(Ohm)
0.115
T=80ºC
104
Vtpwr=2.8V
106
104
102
102
T=-10ºC
100
2.5
3.5
4.5
Vtpwr
Vtpwr=5.8V
100
-20
5.5
Ver 1.3
Jul 19, 2002
0
20
40
60
Temperature(ºC)
80
100
TEL: 886-3-5788833
http://www.gmt.com.tw
6
G218B
Global Mixed-mode Technology Inc.
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
2.93
2.91
2.91
50 150
Ivref(mA)
250
350
Vref - Vtpwr@T=24ºC
2.89
2.89
Vtpwr=5.8V
2.87
Vref
Vref
-50
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
0
20
40
60
Temperature(ºC)
80
100
3.5
4.5
5.5
6.5
Vtpwr
Ver 1.3
Jul 19, 2002
TEL: 886-3-5788833
http://www.gmt.com.tw
7
Global Mixed-mode Technology Inc.
Pin Description
G218B
(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 G218B 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
DESCRIPTION
1
VREF*
2,3
4-7,11-16,
22-25,
29-32
8, 9,10,26,
27,28
17
NC
DISCNCT
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 G218 isolates its bus pins (Rx+, Rx-) from the SCSI bus.
18
GND
19
20
21
33
34
35
36
Rx+
RxHS/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.
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.
Ver 1.3
Jul 19, 2002
TEL: 886-3-5788833
http://www.gmt.com.tw
8
G218B
Global Mixed-mode Technology Inc.
Package Information (28 pin SSOP)
0.25
C
D
28
L
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 1.3
Jul 19, 2002
Max.
TEL: 886-3-5788833
http://www.gmt.com.tw
9
G218B
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 1.3
Jul 19, 2002
0.295
0.420
0.289
0.025
0.040
8
TEL: 886-3-5788833
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10
G218B
Global Mixed-mode Technology Inc.
28 pin TSSOP
C
D
28
L
E1
E
1
θ
A2
A
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
Taping Specification
Feed Direction
Typical SSOP, TSSOP Package Orientation
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.
Ver 1.3
Jul 19, 2002
TEL: 886-3-5788833
http://www.gmt.com.tw
11