G5316 Datasheet, PDF (1/2 Pages) Global Mixed-mode Technology Inc – Complete DDR2, DDR3 and DDR3L Memory Solution Synchronous Buck PWM Controller, 2A LDO, Buffered Reference

Global Mixed-mode Technology
G5316
Complete DDR2, DDR3 and DDR3L Memory
Solution Synchronous Buck PWM Controller,
2A LDO, Buffered Reference
Features
•Synchronous Buck Controller (VDDQ)
„ Ultra-High Efficiency at Light and Heavy Load
with Auto-skip Function
„ No Current-Sense Resistor (Lossless ILIMIT)
„ Quasi-PWM with 100ns Load-Step Response
„ 0.7V to 1.8V Adjustable Output Range
„ 3V to 28V Battery Input Range
„ 0.8% Vref Accuracy
„ Supports Soft-off in S4/S5 States
„ Selectable 300k/400kHz Switching Frequency
„ OVP & UVP of VDDQ Output
„ Drives Large Synchronous-Rectifier FETs
„ Power-Good Indicator
•2-A LDO (VTT), Buffered Reference (VTTREF)
„ VLDOIN Voltage Range: 1.2 V to 3.6 V
„ Requires Only 10µF Ceramic VTT Output Ca-
pacitance
„ Supports High-Z in S3 and Soft-Off in S4/S5
„ Integrated Divider Tracks 1/2 VDDQSNS for
Both VTT and VTTREF
„ Remote Sensing (VTTSNS)
„ ±20mV VTT and 0.8% VTTREF Accuracy
„ 10mA Buffered Reference (VTTREF)
„ Built-In Soft-Start to Reduce the VLDOIN Surg-
ing Current
„ Over Current Protection of VTT Output
„ Thermal Shutdown Protection
Applications
„ Notebook Computers
„ CPU Core Supply
„ Chipset/RAM Supply as Low as 0.7V
General Description
The G5316 is intended for DDR2, DDR3 and DDR3L
memory systems. It integrates a synchronous buck
PWM controller with a 2-A sink-source linear regulator
and buffered reference.
The PWM controller uses constant on-time control
scheme to handle wide input/output voltage ratios with
ease and provides 100ns “instant-on” response to
load transients while maintaining a relatively constant
switching frequency. The G5316 achieves high effi-
ciency at a reduced cost by eliminating the cur-
rent-sense resistor found in traditional current-mode
PWMs. Efficiency is further enhanced by an ability to
drive very large synchronous rectifier MOSFETs. Sin-
gle-stage buck conversion allows these devices to
directly step down high-voltage batteries for the high-
est possible efficiency.
The 2A sink/source tracking termination regulator is
specifically designed for low-cost/ low-external com-
ponent count systems. The regulator contains a high
speed operational amplifier that provides fast load
transient response with only 10µF of ceramic output
capacitance. The G5316 supports remote sensing
functions and all features required to power the DDR2
/DDR3 /DDR3L VTT bus termination according to the
JEDEC specification. In addition, the G5316 includes
integrated sleep-state controls placing VTT in High-Z
in S3 (suspend to RAM) and soft-off for VTT and
VTTREF in S4/S5 (Shutdown).
The G5316 provides OVP, UVP, over current and
thermal shutdown protection functions and is available
in a 20-pin 3X3 TQFN package.
Ordering Information
ORDER
NUMBER
G5316RZ1U
G5316RZ1D
Note: RZ: TQFN3X3-20
1: Bonding Code
U & D : Tape & Reel
MARKING
5316
5316
TEMP.
RANGE
-40°C to +85°C
-40°C to +85°C
PACKAGE
(Green)
TQFN3X3-20
TQFN3X3-20
Ver: 0.9
Jan 18, 2013
TEL: [phone]
http://www.gmt.com.tw
1