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6-Bit Programmable 2-, 3-, 4-Phase

Synchronous Buck Controller

*Patent Pending

FEATURES

Selectable 2-, 3-, or 4-Phase Operation at up to

1 MHz per Phase

14.5 mV Worst-Case Differential Sensing Error over

Temperature

Logic-Level PWM Outputs for Interface to

External High Power Drivers

Active Current Balancing between All Output Phases

Built-In Power Good/Crowbar Blanking Supports

On-the-Fly VID Code Changes

6-Bit Digitally Programmable 0.8375 V to 1.6 V Output

Programmable Short Circuit Protection with

Programmable Latch-Off Delay

APPLICATIONS

Desktop PC Power Supplies for:

VRM Modules

FUNCTIONAL BLOCK DIAGRAM

PWM2

FB

PWM3

PWM4

SW1

CSSUM

CSCOMP

SW2

SW3

SW4

CSREF

PWM1

ADP3180

VID4

VID3

VID2

VID1

VID5

VID0

FBRTN

GND

EN

DELAY

ILIMIT

PWRGD

COMP

VCC

RT

RAMPADJ

CROWBAR

CURRENT

LIMIT

2-, 3-, 4-PHASE

DRIVER LOGIC

EN

SET

RESET

RESET

RESET

RESET

OSCILLATOR

CMP

CMP

CMP

CMP

CURRENT

BALANCING

CIRCUIT

DELAY

UVLO

SHUTDOWN

AND BIAS

DAC

+150mV

DAC

–250mV

CSREF

PRECISION

REFERENCE

SOFT-

START

VID

DAC

EN

CURRENT

LIMIT

CIRCUIT

19

11

12

15

10

28

13

14

26

8

25

24

23

17

18

22

21

20

16

1234

6

5

7

9

27

GENERAL DESCRIPTION

The ADP3180 is a highly efficient multiphase synchronous buck

switching regulator controller optimized for converting a 12 V

main supply into the core supply voltage required by high per-

formance Intel processors. It uses an internal 6-bit DAC to read

a voltage identification (VID) code directly from the processor,

which is used to set the output voltage between 0.8375 V and

1.6 V, and uses a multimode PWM architecture to drive the logic

level outputs at a programmable switching frequency that can be

optimized for VR size and efficiency. The phase relationship of the

output signals can be programmed to provide 2-, 3-, or 4-phase

operation, allowing for the construction of up to four comple-

mentary buck switching stages.

The ADP3180 also includes programmable no-load offset and

slope functions to adjust the output voltage as a function of the

load current so that it is always optimally positioned for a system

transient. The ADP3180 also provides accurate and reliable short

circuit protection, adjustable current limiting, and a delayed

Power Good output that accommodates on-the-fly output voltage

changes requested by the CPU.

ADP3180 is specified over the commercial temperature range of

0°C to 85°C and is available in a 28-lead TSSOP package.

REV. 0