8-Bit, Programmable, 2- to 3-Phase,

Synchronous Buck Controller

ADP3193A

Rev. 0

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FEATURES

Selectable 2- or 3-phase operation at up to 1 MHz per phase

±7.7 mV worst-case differential sensing error over

temperature

Logic-level PWM outputs for interface to external high

power drivers

Fast enhanced PWM (FEPWM) flex mode for excellent load

transient performance

Active current balancing between all output phases

Built-in power-good/crowbar blanking supports on-the-fly

VID code changes

Digitally programmable 0.5 V to 1.6 V output supports both

VR10.x and VR11 specifications

Programmable short-circuit protection with programmable

latch-off delay

APPLICATIONS

Desktop PC power supplies for

Next generation Intel® processors

VRM modules

GENERAL DESCRIPTION

The ADP3193A1 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

performance Intel processors. It uses an internal 8-bit DAC to read

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

which is used to set the output voltage between 0.5 V and 1.6 V.

This device 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 relation-

ship of the output signals can be programmed to provide 2- or

3-phase operation, allowing for the construction of up to three

complementary buck switching stages.

The ADP3193A also includes programmable no load offset and

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

load current, optimally positioning it for a system transient. The

ADP3193A also provides accurate and reliable short-circuit

protection, adjustable current limiting, and delayed power-good

output that accommodates on-the-fly output voltage changes

requested by the CPU.

FUNCTIONAL BLOCK DIAGRAM

SHUNT

REGULATOR

VC DAC

DAC

+150mV

850mV

DAC

–350mV

CSREF

2-/3-PHASE

DRIVER LOGIC

EN

SET

14

1

2

8

7

16

5

3

32

–

+

–

+

UVLO

SHUTDOWN

15

22

21

20

19

18

17

13

11

12

4

6

BOOT

VOLTAGE

AND

SOFT START

CONTROL

DELAY

RESET

RESET

RESET

VID7

24

VID6

25

VID5

26

VID4

27

VID3

28

VID2

29

VID1

30

VID0

31

ADP3193A

+

–

CMP

+

–

CMP

+

–

CMP

CROWBAR

CURRENT

LIMIT

CURRENT

MEASUREMENT

AND LIMIT

PRECISION

REFERENCE

23

9

10

+

–

GND

EN

DELAY

ILIMIT

PWRGD

COMP

FBRTN

VIDSEL

IREF

PWM2

PWM3

SW3

SW2

SW1

CSREF

CSCOMP

CSSUM

FB

PWM1

SS

OD

VCC

RAMPADJ

RT

OSCILLATOR

Figure 1.

The ADP3193A has a built-in shunt regulator that allows the

part to be connected to the 12 V system supply through a series

resistor.

The ADP3193A is specified over the extended commercial

temperature range of 0°C to 85°C and is available in a

32-lead LFCSP.