600 kHz Dual Output Synchronous Buck

PWM Controller with Linear Regulator

Data Sheet

ADP1876

Rev. A

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FEATURES

Wide input range: 2.75 V to 20 V

Power stage input voltage: 1 V to 20 V

Output voltage range: 0.6 V up to 90% V

IN

Linear dropout (LDO) regulator with a fixed output

1.5 V at 150 mA

Output current more than 25 A per channel

180º phase shift between channels for reduced input

capacitance

±0.85% reference voltage accuracy from −40°C to +85°C

Integrated boost diodes

Independent channel precision enable

Overcurrent limit protection

Externally programmable soft start, slope compensation,

and current sense gain

Thermal overload protection

Input undervoltage lockout (UVLO)

Power good with internal pull-up resistor

Available in 32-lead, 5 mm × 5 mm LFCSP

APPLICATIONS

Consumer applications

Telecommunications base station and networking

Industrial and instrumentation

TYPICAL OPERATION CIRCUIT

Figure 1.

GENERAL DESCRIPTION

The ADP1876 is a dual output dc-to-dc synchronous buck

controller operating at 600 kHz fixed frequency with integrated

drivers that drive N-channel power MOSFETs. An additional

fixed voltage output, 150 mA linear regulator is available for

powering low power loads. The device operates in current

mode for improved transient response and uses valley current

sensing for enhanced noise immunity. The two PWM outputs

are phase shifted 180° for reducing the input current ripple and

the required input capacitance.

The ADP1876 provides high speed, high peak current drive

capability with dead time optimization to enable energy

efficient power conversion.

RAMP1

VIN

DH1

BST1

SW1

ILIM1

FB1

DL1

PGND1

RAMP2

DH2

BST2

SW2

ILIM2

FB2

DL2

PGND2

EN1

EN2

VDL

VCCO

TRK1

1.5V

VINLDO

VOUTLDO

NC

COMP1

COMP2

SS1

SS2

AGND

R11

R12

R21

R22

M1

M2

M3

L2

L1

M4

PGOOD1

3V to 5V INPUT

PGOOD2

ADP1876