2 A/1.25 A, 1.2 MHz, Synchronous,

Step-Down DC-to-DC Regulators

ADP2119/ADP2120

Rev. 0

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FEATURES

Continuous output current

ADP2119: 2 A

ADP2120: 1.25 A

145 mΩ and 70 mΩ integrated MOSFETs

Input voltage range from 2.3 V to 5.5 V

±1.5% output accuracy

1.2 MHz fixed switching frequency

Synchronizable between 1 MHz and 2 MHz

Selectable PWM or PFM mode operation

Current mode architecture

Precision threshold enable input

Power-good flag

Voltage tracking

Integrated soft start

Internal compensation

Startup with precharged output

UVLO, OVP, OCP, and thermal shutdown

10-lead, 3 mm × 3 mm LFCSP_WD package

APPLICATIONS

Point of load conversion

Communications and networking equipment

Industrial and instrumentation

Consumer electronics

Medical applications

TYPICAL APPLICATION CIRCUIT

10

EN

ADP2119/ADP2120

1

VIN

9

SYNC/MODE

2

PVIN

8

PGOOD

3

SW

7

TRK

4

PGND

6

FB

5

GND

R2

10k

Ω

5V

22µF

X5R

6.3V

22µF

X5R

6.3V

C1

0.1µF

R1

10

Ω

2.21k

Ω

3.3V

L

1.5µH

10k

Ω

Figure 1.

GENERAL DESCRIPTION

The ADP2119/ADP2120 are low quiescent current, synchronous,

step-down dc-to-dc regulators in a compact 3 mm × 3 mm

LFCSP_WD package. Both devices use a current mode, constant

frequency pulse-width modulation (PWM) control scheme for

excellent stability and transient response. Under light load conditions,

they can be configured to operate in a pulse frequency modulation

(PFM) mode, which reduces switching frequency to save power.

The ADP2119/ADP2120 support input voltages from 2.3 V to

5.5 V. The output voltage can be adjusted from 0.6 V up to the

output version is available in preset output voltage options of 3.3 V,

2.5 V, 1.8 V, 1.5 V, 1.2 V, and 1.0 V. The ADP2119/ADP2120 require

minimal external parts and provide a high efficiency solution with

their integrated power switches, synchronous rectifiers, and internal

compensation. Each IC draws less than 2 μA current from the input

source when it is disabled. Other key features include undervoltage

lockout (UVLO), integrated soft start to limit inrush current at

startup, overvoltage protection (OVP), overcurrent protection

(OCP), and thermal shutdown (TSD).

100

90

80

70

60

50

40

30

20

10

0

0.01

0.1

1

OUTPUT CURRENT (A)

PFM

FPWM

Figure 2. ADP2119 Efficiency vs. Output Current