Micro PMU with 1.2 A Buck Regulator
and Two 300 mA LDOs
Data Sheet
ADP5040
FEATURES
GENERAL DESCRIPTION
Input voltage range: 2.3 V to 5.5 V
One 1.2 A buck regulator
Two 300 mA LDOs
20-lead, 4 mm × 4 mm LFCSP package
Overcurrent and thermal protection
Soft start
The ADP5040 combines one high performance buck regulator
and two low dropout regulators (LDO) in a small 20-lead
LFCSP to meet demanding performance and board space
requirements.
The high switching frequency of the buck regulator enables the use
of tiny multilayer external components and minimizes board space.
Undervoltage lockout
When the MODE pin is set to logic high, the buck regulator
operates in forced pulse width modulation (PWM) mode.
When the MODE pin is set to logic low, the buck regulator
operates in PWM mode when the load is around the nominal
value. When the load current falls below a predefined threshold
the regulator operates in power save mode (PSM) improving
the light-load efficiency. The low quiescent current, low
dropout voltage, and wide input voltage range of the ADP5040
LDOs extend the battery life of portable devices. The ADP5040
LDOs maintain a power supply rejection greater than 60 dB for
frequencies as high as 10 kHz while operating with a low headroom
voltage.
Buck key specifications
Output voltage range: 0.8 V to 3.8 V
Current mode topology for excellent transient response
3 MHz operating frequency
Peak efficiency up to 96%
Uses tiny multilayer inductors and capacitors
Mode pin selects forced PWM or auto PWM/PSM modes
100% duty cycle low dropout mode
LDOs key specifications
Output voltage range: 0.8 V to 5.2 V
Low VIN from 1.7 V to 5.5 V
Stable with 2.2 µF ceramic output capacitors
High PSRR
Low output noise
Each regulator in the ADP5040 is activated by a high level on
the respective enable pin. The output voltages of the regulators
are programmed though external resistor dividers to address a
variety of applications.
Low dropout voltage
−40°C to +125°C junction temperature range
FUNCTIONAL BLOCK DIAGRAM
VOUT1
R
= 30Ω
L1
1µH
FILT
AVIN
SW
V
AT
OUT1
1.2A
FB1
BUCK
AVIN
C6
10µF
R1
R2
VIN1
V
= 2.3V TO
5.5V
IN1
PGND
MODE
C5
4.7µF
EN_BK
ON
FPWM
R3
EN1
OFF
PSM/PWM
VOUT2
FB2
V
AT
LDO1
(DIGITAL)
OUT2
VIN2
V
= 1.7V
TO 5.5V
IN2
300mA
C1
1µF
C2
2.2µF
EN_LDO1
R4
ON
ON
EN2
EN3
OFF
OFF
EN_LDO2
VOUT3
FB3
VIN3
V
AT
V
= 1.7V
TO 5.5V
OUT3
IN3
LDO2
(ANALOG)
300mA
C3
1µF
C4
2.2µF
R7
R3
AGND
Figure 1.
Rev. 0
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