GMT G2992

G2992
Global Mixed-mode Technology Inc.
3A DDR Bus Termination Regulator
Features
General Description
„
The G2992 is a linear regulator designed to meet the
JEDEC SSTL-18, SSTL-2 and SSTL-3 (Series Stub
Termination Logic) specifications for termination of
DDR I / II -SDRAM. It contains a high-speed operational amplifier that provides excellent response to the
load transients. This device can deliver 3A continuous
current in the application such as required for DDR I/ II
SDRAM termination. The G2992 can easily provide
the accurate VTT voltage with two external resistors
generating reference voltage. The quiescent current is
as low as 750µA @ VCNTL = 3.3V. So the power consumption can meet the low power consumption applications. The G2992 also has a shutdown function by
setting VREF smaller than 0.2V, that provides Suspend
to RAM (STR) functionality. When in the shutdown
mode, the VTT output (on VOUT pin) will be tri-state
providing a high impendence. A power saving advantage can be obtained in this mode through lowering
the quiescent current to 50μA @ VCNTL = 3.3V.
„
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VCNTL Supply Voltage: 3.3V to 5.5V
Termination Supply Voltage: 1.8V to 3.6V
Support Both DDR I(1.25VTT) and DDR II (0.9
VTT) Requirements
Requires Only 20µF Ceramic Output Capacitor
Low Output Offset
3A Source and Sink Current
Low External Component Count
No Inductor Required
Thermal Shutdown Protection
Over Current Protection
Suspend to RAM (STR) Function with
High-impedance output
SOP-8 (FD) Package
Applications
„
DDR-SDRAM Termination Voltage
DDR I / DDR II Termination Voltage
„ SSTL-18
„ SSTL-2
„ SSTL-3
„
Ordering Information
ORDER
MARKING
NUMBER
G2992F1U
G2992
TEMP.
RANGE
PACKAGE
(Pb free)
-40°C to +85°C
SOP-8 (FD)
Note: U: Tape & Reel
(FD): Thermal Pad
Pin Configuration
Typical Application Circuit
VCNTL=3.3V
G2992
VIN
GND
8
1
2
7
NC
VIN=2.5V
NC
VREF 3
6
VCNTL
VOUT 4
5
NC
RTT
R1
2N7002
EN
VIN
VREF
R2
CSS
VCNTL
CIN
CCNTL
VOUT
GND
COUT RDUMMY
SOP-8(FD)
TEL: 886-3-5788833
http://www.gmt.com.tw
Ver: 1.0
Aug 29, 2006
1
G2992
Global Mixed-mode Technology Inc.
Absolute Maximum Ratings
Recommend Operation Range (3)
(1)
Supply Voltage
VCNTL to GND. . . . . . . . . . . . . . . . . . . . . . -0.3V to +7V
Maximum Junction Temperature, TJ. . . . . . . . 150°C
Storage Temperature Range, TSTG. . -65°C to+150°C
Reflow Temperature (soldering, 10sec) . . . . . . 260°C
Thermal Resistance Junction to Ambient, (θJA)
SOP-8 (FD). . . . . . . . . . . . . . . . . . . . . . . . . . ..50°C/W
Electrostatic Discharge, VESD
Human body mode. . . . . . . . . . . . . . . . . . . . . 2000V(2)
Operating Ambient Temperature Range
TA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . -40°C to +85°C
VCNTL to GND. . . . . . . . . . . . . . . . . . . . . . 3.3V to 5.5V
VIN to GND. . . . . . . . . . . . . . . . . . . . . . . . 1.8V to 3.6V
VREF to GND . . . . . . . . . . . . . . . . . . . . . . . .0 to VCNTL
Note:
(1)
: Absolute maximum rating indicates limits beyond which damage to the device may occurs.
: Human body model : C = 100pF, R = 1500Ω, 3 positive pulses plus 3 negative pulses.
(3)
:VIN and VREF mustn’t be higher than VCNTL.
(2)
Electrical Characteristics
Specifications with standard typeface are for TA=25°C, VIN=2.5V, VCNTL=3.3V, VREF=1.25V, COUT=20µF.
Unless otherwise specified.
PARAMETER
SYMBOL
Output Offset Voltage
VTT output voltage
VOS
VTT
VTT Output Voltage Load Regulation
(DDR I/DDR II)
∆VTT
Input Voltage Range (DDR I/DDR II)
CONDITIONS
VCNTL
ICNTL
Quiescent Current in Shutdown
Current Limit
Thermal Shutdown Temperature
Thermal Shutdown Hysteresis
Shutdown High Trigger Level Output
ISD
ILIMIT
TTS
THYS
VIH
Shutdown Low Trigger Level Output
VIL
TYP
MAX
UNIT
-20
---
0
1.25/0.9
20
---
mV
V
(DDR I/DDR II)
IVTT=0, VREF=½VIN
-20
---
20
|IVTT|<1.5A,VREF=½VIN
|IVTT|<3A, VREF =½VIN
-30
-40
-----
30
40
mV
1.8
-----
2.5/1.8
3.3
750
3.6
5.5
1500
V
V
µA
---
50
90
µA
3.3V≦VCNTL≦5.5V
3
---
--160
-----
A
°C
---
20
---
°C
Output active
Output disable
0.8
---
-----
--0.2
V
V
VIN
Control Voltage Range (DDR I/DDR II)
Quiescent Current
MIN
IOUT=0A
VREF<0.2V
TEL: 886-3-5788833
http://www.gmt.com.tw
Ver: 1.0
Aug 29, 2006
2
G2992
Global Mixed-mode Technology Inc.
Typical Performance Characteristics
CCNTL=1µF/MLCC/X5R, CIN=22µF/MLCC/X7R, CSS=1µF/MLCC/X5R, COUT=20µF/X5R/MLCC unless otherwise noted.
VOUT is Shorted to GND
VOUT is Shorted to VIN (2.5V)
VCNTL=5.0V,VIN=2.5V
VCNTL=5.0V,VIN=2.5V
VOUT Load Transient Response
VOUT Load Transient Response
VCNTL=5.0V,VIN=2.5V
VCNTL=5.0V,VIN=1.8V
Sourcing Current Limit vs Temperature
Sourcing Current Limit vs Temperature
5.6
4
5.4
3.9
Sourcing Current Limit (A)
Sourcing Current Limit (A)
5.2
5
4.8
4.6
4.4
VCNTL=3.3V,VIN=1.8V
4.2
4
3.8
VCNTL=5.5V,VIN=1.8V
3.6
3.8
VCNTL=3.3V,VIN=2.5V
3.7
3.6
3.5
VCNTL=5.5V,VIN=2.5V
3.4
3.4
3.2
-40
3.3
-20
0
20
40
60
80
100
120
-40
-20
0
20
40
60
80
100
120
Temperature (°C)
Temperature (°C)
TEL: 886-3-5788833
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Ver: 1.0
Aug 29, 2006
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G2992
Global Mixed-mode Technology Inc.
Typical Performance Characteristics (continued)
Sinking Current Limit vs Temperature
4.4
4.3
4.3
4.2
4.2
VCNTL=5.5V,VIN=1.8V
4.1
Sinking Current Limit (A)
Sinking Current Limit (A)
Sinking Current Limit vs Temperature
4.4
4
3.9
3.8
3.7
3.6
3.5
VCNTL=3.3V,VIN=1.8V
3.4
3.9
3.8
3.7
3.6
3.5
3.2
-20
0
20
40
60
80
Temperature (°C)
100
-40
120
-20
40
60
80
100
120
1.2
1.15
VCNTL Supply Current (mA)
0.7
0.6
VCNTL=5V
0.5
0.4
VCNTL=3.3V
0.3
VCNTL=5.0V,VIN=1.8V
1.1
1.05
1
0.95
0.9
0.85
0.8
0.2
-20
0
20
40
60
Temperature (°C)
80
100
-2
120
-1.5
-1
-0.5
0
0.5
1
1.5
2
100
120
VOUT Load Current (A)
RDS(ON) vs Temperature
RDS(ON) vs Temperature
0.16
0.18
0.17
0.15
VIN=0.9V
0.16
VIN=0.85V
VIN=0.9V
0.14
0.15
RDS(ON) (Ω)
RDS(ON) (Ω)
20
VCNTL Supply Current vs Vout Load Current
VREF Shutdown Threshold vs Temperature
0.14
VIN=0.8V
0.13
VIN=0.85V
0.13
0.12
VIN=0.8V
0.11
0.12
VCNTL=3.3V
0.11
0.1
VCNTL=5.0V
0.09
0.1
-40
0
Temperature (°C)
0.8
VREF Shutdown Threshold (V)
VCNTL=3.3V,VIN=2.5V
3.3
3.2
-40
VCNTL=5.5V,VIN=2.5V
4
3.4
3.3
-40
4.1
-20
0
20
40
60
80
100
-40
120
Temperature (°C)
-20
0
20
40
60
80
Temperature (°C)
TEL: 886-3-5788833
http://www.gmt.com.tw
Ver: 1.0
Aug 29, 2006
4
G2992
Global Mixed-mode Technology Inc.
Typical Performance Characteristics (continued)
VCNTL Supply Current vs. VCNTL
Supply Voltage
1
1
0.95
0.95
VCNTL Supply Current (mA)
VCNTL Supply Current (mA)
VCNTL Supply Current vs Temperature
0.9
0.85
0.8
0.75
0.7
0.85
TA=25°C
0.8
0.75
0.7
VCNTL=5.0V,VIN=2.5V
0.65
TA=120°C
0.9
TA=0°C
0.65
-40
-20
0
20
40
60
80
100
120
3.3
3.6
3.9
Temperature (°C)
62
69
60
66
VCNTL Shutdown Current (µA)
VCNTL Shutdown Current (µA)
5.7
6
VCNTL Shutdown Current vs VCNTL
Supply Voltage
VCNTL Shutdown Current vs Temperature
58
56
54
52
50
VCNTL=5.0V,VIN=2.5V
48
4.2 4.5 4.8 5.1 5.4
VCNTL Supply Voltage (V)
63
60
TA=120°C
57
54
TA=25°C
51
48
TA=0°C
45
46
-40
-20
0
20
40
60
Temperature (°C)
80
100
3.3
120
3.9
4.2
4.5
4.8
5.1
5.4
5.7
6
VCNTL Supply Voltage (V)
VIN Dropout Voltage vs Output Current
Recommended Minimum Footprint
1.2
SOP-8 (FD)
VREF=0.9V
VCNTL=3.3V
1
3.6
Dropout Voltage (V)
TA=25°C
0.8
TA=75°C
0.6
TA=125°C
0.4
0.2
TA=-50°C
0
0
0.5
1
1.5
2
2.5
3
Output Current (A)
TEL: 886-3-5788833
http://www.gmt.com.tw
Ver: 1.0
Aug 29, 2006
5
G2992
Global Mixed-mode Technology Inc.
Pin Description
PIN
NAME
1
2
VIN
GND
Terminator Power pin.
Ground
FUNCTION
3
VREF
Terminator reference input voltage, 1.25V for DDR I, 0.9V for DDR II. Below 0.2V, the chip
will be shutdown.
4
VOUT
Terminator output pin (VTT voltage supplied)
5,7,8
6
NC
VCNTL
No Connection
Internal circuit power pin, at least 3.3V
Block Diagram
VIN
VCNTL
Shutdown
VREF
+
VOUT
GND
Application Information
voltage which is generated by a resistor divider between VIN and GND. Using a capacitor tapped to the
voltage divider can form a low-pass filter. It can increase both the soft-start interval and the noise immunity.
Output Capacitor
For stable operation, total capacitance of the VTT output terminal can be equal or greater than 20µF. The
output capacitor should be located near VTT output
terminal as close as possible to minimize the effect of
ESR and ESL.
Input Capacitor
Adding a capacitance close to VIN pin can improve the
VTT performance when fast load- transient. In general,
1/2 COUT is recommended for the VIN capacitance.
Separating the VIN and VCNTL pins will get better transient performance.
Power on sequence
For safely operation, The G2992 must keep VCNTL
voltage larger than VIN, this condition is due to the internal parasitic diodes between VIN to VCNTL. The
G2992 will consume large current when VIN voltage is
larger than VCNTL.
A ceramic capacitance with a value between 1.0µF
and 4.7µF close to the VCNTL pin is recommended to
stabilize the VCNTL voltage.
Consideration of the VREF Voltage
The VREF voltage is applied by a buffered mid-rail
TEL: 886-3-5788833
http://www.gmt.com.tw
Ver: 1.0
Aug 29, 2006
6
G2992
Global Mixed-mode Technology Inc.
Package Information
D1
0.008TYP
E1
E
H
L
D
θ
0.015x45º
A2
0.004MAX.
e
A
SEATING PLANE
A1
B
SOP- 8 (F1) Package
Note:
1. JEDEC Outline: MS-012 AA/E.P. Version: N/A
2. Dimension “D” does not include mold flash, protrusions or gate burrs. Mold flash, protrusions and gate burrs
shall not exceed .15mm (.006in) per side.
3. Dimensions “E” does not include inter-lead flash, or protrusions inter-lead flash and protrusions shall not exceed .25mm (.010in) per side.
SYMBOL
A
A1
A2
B
D
MIN.
DIMENSION IN MM
MAX.
1.35
0.00
-----
DIMENSION IN INCH
MIN.
MAX.
1.75
0.13
1.50
0.053
0.000
-----
4.98
0.189
3.99
0.150
0.41TYP
4.80
0.069
0.005
0.059
0.016TYP
0.196
E
e
3.81
H
L
θ
5.80
0.41
6.20
1.27
0.228
0.016
0.244
0.050
0º
---------
8º
2.29
2.29
0º
---------
8º
0.090
0.090
1.27TYP
D1
E1
0.157
0.05TYP
Taping Specification
PACKAGE
Q’TY/REEL
SOP-8 (FD)
2,500 ea
Feed Direction
Typical SOP 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.
TEL: 886-3-5788833
http://www.gmt.com.tw
Ver: 1.0
Aug 29, 2006
7