Power Management Unit
for Imaging Modules
ADP5020
TYPICAL APPLICATIONS CIRCUIT
FEATURES
V
IN
2.4V TO 5.5V
Input voltage range: 2.4 V to 5.5 V
Low standby current: 1 μA
Switching frequency: 3 MHz
I2C interface
Synchronous Buck 1 regulator: 600 mA
Synchronous Buck 2 regulator: 250 mA
Low dropout regulator (LDO): 150 mA
Internal compensation
SW1
VDD1
VDD2
VDD3
VDDA
10µF
2.2µH
V
OUT1
2.5V TO 3.7V
VOUT1
VOUT1
10µF
PGND1
V
OUT2
ADP5020
2.2µH
1.1V TO 1.8V
SW2
Internal soft start
Thermal shutdown
1µF
4.7µF
VOUT2
V
DD_IO
1.7V TO 3.6V
VDD_IO
PGND2
VOUT3
20-lead 4 mm × 4 mm LFCSP
V
OUT3
1.8V TO 3.3V
10kΩ 10kΩ
0.1µF
APPLICATIONS
Digital cameras, handsets
Mobile TVs
1µF
SDA
SCL
EXT. FREQ
9.6/19.2MHz
SYNC
XSHTDN
EN/GPIO
DGND
AGND
Figure 1.
GENERAL DESCRIPTION
The ADP5020 provides a highly integrated power solution that
includes all of the power circuits necessary for a digital imaging
module. It comprises two step-down dc-to-dc converters, one
LDO, and a power sequence controller. All dc-to-dc converters
integrate power pMOSFETs and nMOSFETs, making the system
simpler and more compact and reducing the cost. The ADP5020
has digitally programmed output voltages and buck converters
that can source up to 600 mA. A fixed frequency operation of
3 MHz enables the use of tiny inductors and capacitors. The buck
converters use a voltage mode, constant-frequency PWM control
scheme, and the synchronous rectification is implemented to
reduce the power loss. The Buck 1 regulator operates at up to
93% efficiency.
The ADP5020 provides high performance, reduces component
count and size, and is lower in cost when compared to conven-
tional designs.
The ADP5020 runs on input voltage from 2.4 V to 5.5 V and
supports one-cell lithium-ion (Li+) batteries. The high perfor-
mance LDO maximizes noise suppression. The ADP5020 can be
activated via an I2C® interface or through a dedicated enable input.
During logic-controlled shutdown, the input is disconnected
from the output source, and the part draws 1 μA typical from
the input source. Other key features include undervoltage lockout
to prevent deep-battery discharge and soft start to prevent input
current overshoot at startup. The ADP5020 is available in a
20-lead LFCSP.
Rev. 0
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