1

2

3

4

24

23

22

21

DRVH2

VIN

VREG3

EN2

DRVH1

V5SW

RF

EN1

TPS51220RHB

(QFN32)

5

6

7

8

20

19

18

17

PGOOD2

SKIPSEL2

CSP2

CSN2

PGOOD1

SKIPSEL1

CSP1

CSN1

9

32

31

30

29

28

27

26

25

10

11

12

13

14

15

16

VO1

5.0V

L1

C22

VBAT

PowerPAD

C02

C01

VREG5

5V/100mA

R23

R13

C11

R11

PGOOD1

EN

EN1

VREG3

3.3V/10mA

Q11

Q12

Q22

Q21

C13

R12

GND

R14

GND

GND

GND

L2

R24

GND

C23

C21

R21

R22

GND

PGOOD2

EN2

VO2

3.3V

C03

R01

PGND

GND

SKIPSEL1

SKIPSEL2

VBAT

VO2

C12

VBAT

VO1

VO1

VREG5

C14

PGND

PGND

PGND

PGND

PGND

PGND

PGND

C24

GND

TPS51220

www.ti.com

SLVS785C – OCTOBER 2007 – REVISED JULY 2009

Fixed Frequency, 99% Duty Cycle Peak Current Mode Notebook System Power Controller

Check for Samples: TPS51220

1

FEATURES

2

•

Input Voltage Range: 4.5 V to 28 V

•

Powergood Output for Each Channel

•

Output Voltage Range: 1 V to 12 V

•

OCL/OVP/UVP/UVLO Protections

(OVP Disable Option)

•

Selectable Light Load Operation

(Continuous / Auto Skip / Out-Of-Audio™ Skip)

•

Thermal Shutdown (Non-Latch)

•

Programmable Droop Compensation

•

Output Discharge Function (Disable Option)

•

Voltage Servo Adjustable Soft Start

•

Integrated Boot Strap MOSFET Switch

•

200 kHz to 1 MHz Fixed Frequency PWM

•

QFN-32 (RHB)

•

Selectable Current/ D-CAP™ Mode

APPLICATIONS

Architecture

•

Notebook Computer System and I/O Bus

•

180° Phase Shift Between Channels

•

Point of Load in LCD TV, MFP

•

Resistor or Inductor DCR Current Sensing

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

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.

2

Out-Of-Audio, D-CAP, PowerPAD are trademarks of Texas Instruments.

PRODUCTION DATA information is current as of publication date.

Copyright © 2007–2009, Texas Instruments Incorporated

Products conform to specifications per the terms of the Texas

Instruments standard warranty. Production processing does not

necessarily include testing of all parameters.