TPS51116 Datasheet, PDF (1/29 Pages) Texas Instruments – COMPLETE DDR AND DDR2 MEMORY POWER SOLUTION SYNCHRONOUS BUCK CONTROLLER, 3-A LDO, BUFFERED REFERENCE

TPS51116
www.ti.com
SLUS609A – MAY 2004 – REVISED JUNE 2004
COMPLETE DDR AND DDR2 MEMORY POWER SOLUTION
SYNCHRONOUS BUCK CONTROLLER, 3-A LDO, BUFFERED REFERENCE
FEATURES
• Synchronous Buck Controller (VDDQ)
– Wide-Input Voltage Range: 3.0-V to 28-V
– D–CAP™ Mode with 100-ns Load Step Re-
sponse
– Current Mode Option Supports Ceramic
Output Capacitors
– Supports Soft-Off in S4/S5 States
– Current Sensing from R_DS(on) or Resistor
– 2.5-V (DDR), 1.8-V (DDR2) or Adjustable
Output (1.5-V to 3.0-V)
– Equipped with Powergood, Overvoltage Pro-
tection and Undervoltage Protection
• 3-A LDO (VTT), Buffered Reference (VREF)
– Capable to Sink and Source 3 A
– LDO Input Available to Optimize Power
Losses
– Requires only 20-µF Ceramic Output Ca-
pacitor
– Buffered Low Noise 10-mA Output
– Accuracy ±20 mV for both VREF and VTT
– Supports High-Z in S3 and Soft-Off in S4/S5
– Thermal Shutdown
DESCRIPTION
The TPS51116 provides a complete power supply for
both DDR/SSTL-2 and DDR2/SSTL-18 memory sys-
tems. It integrates a synchronous buck controller with
a 3-A sink/source tracking linear regulator and
buffered low noise reference. The TPS51116 offers
the lowest total solution cost in systems where space
is at a premium. The TPS51116 synchronous control-
ler runs fixed 400kHz pseudo-constant frequency
PWM with an adaptive on-time control that can be
configured in D-CAP™ Mode for ease of use and
fastest transient response or in current mode to
support ceramic output capacitors. The 3-A
sink/source LDO maintains fast transient response
only requiring 20-µF (2 × 10 µF) of ceramic output
capacitance. In addition, the LDO supply input is
available externally to significantly reduce the total
power losses. The TPS51116 supports all of the
sleep state controls placing VTT at high-Z in S3
(suspend to RAM) and discharging VDDQ, VTT and
VTTREF (soft-off) in S4/S5 (suspend to disk). The
TPS51116 has all of the protection features including
thermal shutdown and is in a 20-pin HTSSOP
PowerPAD™ package.
APPLICATIONS
• DDR/DDR2 Memory Power Supplies
• SSTL-2 SSTL-18 and HSTL Termination
TYPICAL APPLICATION
(DDR2)
VTT
0.9 V
2A
GND
C3
Ceramic
2 × 10 µF
VREF
0.9 V
10 mA
GND
C4
Ceramic
0.033 µF
TPS51116PWP
C1
Ceramic
1 VLDOIN VBST 20
2 VTT
0.1 µF
DRVH 19
3 VTTGND
LL 18
L1
1 µH
4 VTTSNS DRVL 17
5 GND
PGND 16
R1
6 MODE
CS 15
7 VTTREF V5IN 14
8 COMP PGOOD 13
9 VDDQSNS S5 12
R2
PGOOD
S5
10 VDDQSET S3 11
S3
V_IN
C5
Ceramic
2 × 10 µF
C8
SP−CAP
2 × 150 µF
VDDQ
1.8 V
10 A
C2
Ceramic
4.7 µF
5V_IN
UDG−04058
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2004, Texas Instruments Incorporated