Dual 3 MHz, 1200 mA Buck
Regulators with Two 300 mA LDOs
ADP5034
Data Sheet
4 mm LFCSP to meet demanding performance and board space
requirements.
FEATURES
Main input voltage range: 2.3 V to 5.5 V
The high switching frequency of the buck regulators enables tiny
multilayer external components and minimizes the board space.
When the MODE pin is set to high, the buck regulators operate in
forced PWM mode. When the MODE pin is set to low, the buck
regulators operate in PWM mode when the load is above a pre-
defined threshold. When the load current falls below a predefined
threshold, the regulator operates in power save mode (PSM),
improving the light load efficiency.
Two 1200 mA buck regulators and two 300 mA LDOs
24-lead, 4 mm × 4 mm LFCSP package
Regulator accuracy: 3ꢀ
Factory programmable or external adjustable VOUTx
3 MHz buck operation with forced PWM and auto PWM/PSM
modes
BUCK1/BUCK2: output voltage range from 0.8 V to 3.8 V
LDO1/LDO2: output voltage range from 0.8 V to 5.2 V
LDO1/LDO2: low input supply voltage from 1.7 V to 5.5 V
LDO1/LDO2: high PSRR and low output noise
The two bucks operate out of phase to reduce the input capaci-
tor requirement. The low quiescent current, low dropout voltage,
and wide input voltage range of the ADP5034 LDOs extend the
battery life of portable devices. The ADP5034 LDOs maintain
power supply rejection greater than 60 dB for frequencies as
high as 10 kHz while operating with a low headroom voltage.
APPLICATIONS
Power for processors, ASICS, FPGAs, and RF chipsets
Portable instrumentation and medical devices
Space constrained devices
Regulators in the ADP5034 are activated through dedicated
enable pins. The default output voltages can be externally set in
the adjustable version, or factory programmable to a wide range
of preset values in the fixed voltage version.
GENERAL DESCRIPTION
The ADP5034 combines two high performance buck regulators
and two low dropout (LDO) regulators in a small, 24-lead 4 mm ×
TYPICAL APPLICATION CIRCUIT
AVIN
HOUSEKEEPING
C
0.1µF
AVIN
VOUT1
L1 1µH
VIN1
SW1
FB1
2.3V TO
5.5V
V
AT
OUT1
1200mA
C1
R1
R2
4.7µF
BUCK1
MODE
C5
10µF
PGND1
ON
EN1
VIN2
EN2
EN1
OFF
PWM
MODE
PSM/PWM
VOUT2
MODE
L2 1µH
SW2
FB2
C2
4.7µF
V
AT
OUT2
1200mA
R3
R4
BUCK2
C6
10µF
EN2
EN3
PGND2
EN3
VOUT3
FB3
V
AT
OUT3
300mA
LDO1
(ANALOG)
R5
R6
VIN3
1.7V TO
5.5V
C7
1µF
C3
1µF
EN4
ON
VOUT4
FB4
V
AT
EN4
OUT4
300mA
OFF
LDO2
(DIGITAL)
R7
R8
VIN4
C8
1µF
C4
1µF
ADP5034
AGND
Figure 1.
Rev. A
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