TPS51220_15 Datasheet, PDF (1/43 Pages) Texas Instruments – Fixed Frequency, 99% Duty Cycle Peak Current Mode Notebook System Power Controller

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TPS51220
SLVS785C – OCTOBER 2007 – REVISED JULY 2009
Fixed Frequency, 99% Duty Cycle Peak Current Mode Notebook System Power Controller
Check for Samples: TPS51220
FEATURES
1
•2 Input Voltage Range: 4.5 V to 28 V
• Output Voltage Range: 1 V to 12 V
• Selectable Light Load Operation
(Continuous / Auto Skip / Out-Of-Audio™ Skip)
• Programmable Droop Compensation
• Voltage Servo Adjustable Soft Start
• 200 kHz to 1 MHz Fixed Frequency PWM
• Selectable Current/ D-CAP™ Mode
Architecture
• 180° Phase Shift Between Channels
• Resistor or Inductor DCR Current Sensing
• Powergood Output for Each Channel
• OCL/OVP/UVP/UVLO Protections
(OVP Disable Option)
• Thermal Shutdown (Non-Latch)
• Output Discharge Function (Disable Option)
• Integrated Boot Strap MOSFET Switch
• QFN-32 (RHB)
APPLICATIONS
• Notebook Computer System and I/O Bus
• Point of Load in LCD TV, MFP
DESCRIPTION
The TPS51220 is a dual synchronous buck regulator controller with 2 LDOs. It is optimized for 5-V/3.3-V system
controller, enabling designers to cost effectively complete 2-cell to 4-cell notebook system power supply. The
TPS51220 supports high efficiency, fast transient response and 99% duty cycle operation. It supports supply
input voltage ranging from 4.5 V to 28 V, and output voltages from 1 V to 12 V. Two types of control schemes
can be chosen depending on the application. Peak current mode supports stability operation with lower ESR
capacitor and output accuracy. The D-CAP mode supports fast transient response. The high duty (99%)
operation and the wide input/output voltage range supports flexible design for small mobile PCs and a wide
variety of other applications. The fixed frequency can be adjusted from 200 kHz to 1 MHz by a resistor, and each
channel runs 180° out of phase. The TPS51220 can also synchronize to the external clock, and the interleaving
ratio can be adjusted by its duty. The TPS51220 is available in the 32 pin 5x5 QFN package and is specified
from –40°C to 85°C.
Figure 1. TYPICAL APPLICATION CIRCUIT
VO1
5.0 V
VBAT
L1
C11
PGND
Q11
C12
PGND
Q12
PGND
VO1
R01
VREG5
5V/100mA
C01
C14
C24
PGND
GND
PGND
32 31 30 29 28 27 26 25
1 _DRVH1
2 V5SW
3 RF
24
DRVH2
VIN 23
VREG3 22
GND EN1
PGOOD1
4 EN1
5 PGOOD1
TPS51220RHB
(QFN32)
EN2 21
PGOOD2 20
SKIPSEL1
R14
6 SKIPSEL1
7 CSP1
C13
8
CSN1
PowerPAD
SKIPSEL2 19
CSP2 18
CSN2 ₁₇
VBAT
Q21 C22
L2
PGND
Q22
C21
VO2
3.3 V
PGND
PGND
C03
EN2
PGOOD2
GND
SKIPSEL2
R24
C23
VBAT
VREG3
3.3V/10mA
EN
VO1
GND
R11
R12
9 10 11 12 13 14 15 16
GND
R23
R21
R22
R13
C02
VREG5
VO2
GND
GND
GND
1
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.
Out-Of-Audio, D-CAP, PowerPAD are trademarks of Texas Instruments.
2
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 © 2007–2009, Texas Instruments Incorporated