TPS51511_15 Datasheet, PDF (1/30 Pages) Texas Instruments – Synchronous Switcher Controller With 2-A LDO for GPU Power

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TPS51511
SLVS735A – FEBRUARY 2007 – REVISED APRIL 2007
Synchronous Switcher Controller With 2-A LDO for GPU Power
FEATURES
• Switcher Controller:
– Adjustable-Output Buck Converter, 0.75 V
to 3.3 V
– Wide Input Voltage Range: 3.0-V to 28-V
– D-CAP™ Mode with 100-ns Load Step
Response
– Current Mode Option Supports Ceramic
Output Capacitors
– Current Sensing From R_DS(ON) or Resistor
– Internal Switch Supports Dynamic Output
Voltage Change
– Advanced PGOOD Mask Feature
– Equipped With PGOOD, OVP and UVP
– Output Discharge
– 5 V UVLO Protection
• LDO Regulator:
– 2-A LDO for GPU I/O Power
– Input Range: Up to 5 V
– Output Range: 0.75 V to 3.3 V
– Requires Only 20-µF Ceramic Output
Capacitor for LDO Output
– Optional PGOOD
– Output Discharge
– Thermal Shutdown
APPLICATIONS
• GPU Power
• Notebook Computers
DESCRIPTION
The TPS51511 is a 350-kHz D-CAP-mode
synchronous switcher with a 2-A, source-only low
drop-out (LDO) regulator. It is specifically designed
for low cost/low noise/low external-component count
power systems for GPU applications. The integrated
'OD' switch in the buck controller supports dynamic
output voltage change. The current mode option of
the synchronous buck converter can support pure
output ceramic-capacitor applications. The
open-drain LDO power-good signal can be accessed
through the OD pin when it is needed in the
application. The TPS51511 is available in the
thermally-enhanced 20-pin QFN package, and is
specified from –40°C to 85°C.
+1.8 V_LDOIN
PCI Express I/O
+1.2 V/ 2 A
ODOFF = Lo, 1.2 V
ODOFF = Hi, 1.1 V
1
20
2 NC
3 _VLDO
4 _VLDOFB
5 GND
6 ODOFF
7 OD
8 _COMP
9 ^VOSW
TPS51511
DRVH 19
LL 18
DRVL 17
PGND 16
CS 15
V5IN 14
PGOOD 13
ENSW 12
10
11
V_I = 3 V to 28 V
GPU_core
+1.1 V_Lower Power
+1.2 V_Performance
+5 V
PGOOD
ENSW
ENLDO
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.
D-CAP, PowerPAD are trademarks of Texas Instruments.
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 © 2007, Texas Instruments Incorporated