Dual 5 A, 20 V Synchronous Step-Down
Regulator with Integrated High-Side MOSFET
Data Sheet
Rev. 0
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FEATURES
Input voltage: 4.5 V to 20 V
±1% output accuracy
Integrated 48 mΩ typical high-side MOSFET
Flexible output configuration
Dual output: 5 A/5 A
Parallel single output: 10 A
Programmable switching frequency: 250 kHz to 1.2 MHz
External synchronization input with programmable phase
shift or internal clock output
Selectable PWM or PFM mode operation
Adjustable current limit for small inductors
External compensation and soft start
Startup into precharged output
Supported by ADIsimPower
TM
design tool
APPLICATIONS
Communications infrastructure
Networking and servers
Industrial and instrumentation
Healthcare and medical
Intermediate power rail conversion
TYPICAL APPLICATION CIRCUIT
Figure 1.
GENERAL DESCRIPTION
The ADP2325 is a full featured, dual output, step-down dc-to-dc
regulator based on a current mode architecture. The ADP2325
integrates two high-side power MOSFETs and two low-side drivers
for the external N-channel MOSFETs. The two pulse-width mod-
ulation (PWM) channels can be configured to deliver dual 5 A
outputs or a parallel-to-single 10 A output. The regulator operates
from input voltages of 4.5 V to 20 V, and the output voltage can
be as low as 0.6 V.
The switching frequency can be programmed from 250 kHz to
1.2 MHz, or it can be synchronized to an external clock to
minimize interference in multirail applications. The dual PWM
channels run 180° out of phase, thereby reducing input current
ripple as well as reducing the size of the input capacitor.
The bidirectional synchronization pin can be programmed at
a 60°, 90°, or 120° phase shift to provide for a stackable, multi-
phase power solution.
The ADP2325 can be configured to operate in pulse frequency
modulation (PFM) mode at a light load for higher efficiency or
in forced PWM mode for noise sensitive applications. External
compensation and soft start provide design flexibility.
Independent enable inputs and power-good outputs provide
reliable power sequencing. To enhance system reliability, the device
includes undervoltage lockout (UVLO), overvoltage protection
(OVP), overcurrent protection, and thermal shutdown.
The ADP2325 operates over the −40°C to +125°C junction
temperature range and is available in a 32-lead LFCSP_WQ
package.
Figure 2. Efficiency vs. Output Current at V
IN
= 12 V, f
SW
= 600 kHz
BST1
PVIN1
SW1
DL1
PGND
SW2
DL2
EN1
PGOOD1
SS1
COMP1
FB1
BST2
PVIN2
EN2
SS2
COMP2
FB2
PGOOD2
GND
SYNC
SCFG
INTVCC
RT
VDRV
V
OUT1
V
OUT2
V
IN
ADP2325
L1
L2
C
OUT1
C
OUT2
C
IN1
M1
M2
R
OSC
C
BST1
C
SS2
C
C2
R
C2
R
TOP1
R
BOT2
R
TOP2
C
INT
C
DRV
TRK1
TRK2
MODE
V
IN
C
IN2
C
BST2
R
BOT1
R
C1
C
C1
C
SS1
10036-001
50
55
60
65
70
75
80
85
90
95
100
0 1.0 2.0 3.0 4.00.5 1.5 2.5 3.5 4.5 5.0
EFFICIENCY (%)
OUTPUT CURRE NT (A)
V
OUT
= 5.0V
V
OUT
= 3.3V
10036-002