Adjustable Output 1-/2-/3-Phase

Synchronous Buck Controller

ADP3182

Rev. 0

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FEATURES

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

phase

±2% worst-case differential sensing error over temperature

Externally adjustable 0.8 V to >5 V output from a 12 V supply

Logic-level PWM outputs for interface to external high

power drivers

Active current balancing between all output phases

Built-in power good/crowbar functions

Programmable short-circuit protection with programmable

latch-off delay

APPLICATIONS

Auxiliary supplies

DDR memory supplies

Point-of-load modules

GENERAL DESCRIPTION

The ADP3182 is a highly efficient multiphase, synchronous,

buck-switching regulator controller optimized for converting a

12 V main supply into a high current, low voltage supply for use

in point-of-load (POL) applications. It 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 1-, 2-, or 3-phase operation, allowing

for the construction of up to three complementary buck-

switching stages. The ADP3182 also provides accurate and

reliable short-circuit protection and adjustable current limiting.

ADP3182 is specified over the commercial temperature range of

0°C to +85°C and is available in a 20-lead QSOP package.

FUNCTIONAL BLOCK DIAGRAM

VCC

800mV

REFERENCE

SOFT

START

DELAY

UVLO

SHUTDOWN

& BIAS

OSCILLATOR

GND

ADP3182

14

1

RT

8

RAMPADJ

9

PWM2

19

3

FB

PWM3

18

SW1

17

CSSUM

12

CSCOMP

13

SW2

16

SW3

15

CSREF

11

PWM1

FBRTN

2

950mV

1.05V

650mV

FB

FB

EN

CURRENT

LIMIT

CIRCUIT

CROWBAR

CURRENT

LIMIT

CURRENT

BALANCING

CIRCUIT

2 / 3-PHASE

DRIVER LOGIC

EN

SET

RESET

RESET

RESET

20

CMP

CMP

CMP

Figure 1.