Global Mixed-mode Technology
G2997B
General Description
The G2997B is a 2A sink/source tracking termination
regulator. It is specifically designed for low-cost/
low-external component count systems. The G2997B
maintains a high speed operational amplifier that pro-
vides fast load transient response and only requires
20µF (2x10µF) of ceramic output capacitance. The
G2997B supports remote sensing functions and all
features required to power the DDR I / DDR II /DDRIII
/DDR IIIL VTT bus termination according to the
JEDEC specification. In addition, the G2997B includes
integrated sleep-state controls placing VTT in High-Z
in S3 (suspend to RAM) and soft-off for VTT and
VTTREF in S5 (Shutdown). The G2997B is available
in MSOP-10 and MSOP-10 (FD).
DDR Termination Regulator
Features
Support DDR I (1.25VTT), DDR II (0.9 VTT),
DDR III (0.75 VTT), and DDR IIIL (0.675VTT)
Requirements
Input Voltage Range: 3V to 5.5V
VLDOIN Voltage Range: 1.2V to 3.6V
Requires Only 20µF Ceramic Output Capaci-
tance
Supports High-Z in S3 and Soft-Off in S5
Integrated Divider Tracks 1/2 VDDQSNS for
Both VTT and VTTREF
Remote Sensing (VTTSNS)
±20mV
Accuracy for VTT and VTTREF
10mA Buffered Reference (VTTREF)
Built-In Soft-Start
Over Current Protection
Thermal Shutdown Protection
MSOP-10 & MSOP-10 (FD) Package
Ordering Information
ORDER
NUMBER
G2997BP71U
G2997BF61U
Applications
DDR I/II/III/IIIL Memory Termination
SSTL−2, SSTL−18
HSTL Termination
MARKING
G2997
G2997B
TEMP.
RANGE
-40°C~85°C
-40°C~85°C
PACKAGE
(Green)
MSOP-10
MSOP-10 (FD)
Note: P7: MSOP-10 F6: MSOP-10 (FD)
1: Bonding Code
U: Tape & Reel
Pin Configuration
G2997B
VDDQSNS
VLDOIN
VTT
PGND
VTTSNS
1
2
3
4
5
10
9
8
7
6
VIN
S5
GND
S3
VTTREF
VDDQSNS
VLDOIN
VTT
PGND
VTTSNS
1
2
3
4
5
Thermal
Pad
G2997B
10
9
8
7
6
VIN
S5
GND
S3
VTTREF
C1
2x10µF
1.8V
DDR II
DDR II
VTT
PGND
VTTSNS
VDDQSNS
VLDOIN
VIN
S5
GND
S3
VTTREF
C2
0.1µF
R
S5
10kΩ
R
S3
10kΩ
VIN=5V
S5
S3
MSOP-10
Top View
MSOP-10 (FD)
Note: Recommend connecting the Thermal Pad to
the GND for excellent power dissipation.
Typical Application Circuit
DDR I
2.5V
VDDQSNS
VLDOIN
VTT
PGND
C1
2x10µF
VTTSNS
VIN
S5
GND
S3
VTTREF
C2
0.1µF
R
S5
10kΩ
R
S3
10kΩ
VIN=5V
S5
1.5V
DDR III*
DDR II
VTT
S3
C1
2x10µF
PGND
VTTSNS
VDDQSNS
VLDOIN
VIN
S5
GND
S3
VTTREF
C2
0.1µF
R
S5
10kΩ
R
S3
10kΩ
VIN=3.3V
S5
S3
* Recommended V
IN
=3.3V
Ver: 0.8
Nov 22, 2011
TEL: 886-3-5788833
http://www.gmt.com.tw
1
GMT [ GLOBAL MIXED-MODE TECHNOLOGY INC ]
