DATASHEET
ISL9305H
FN7724
Rev 2.00
March 7, 2014
2
3MHz Dual 1.5A Step-Down Converters and Dual Low-Input LDOs with I C
Compatible Interface
The ISL9305H is an integrated mini Power Management IC
(mini-PMIC) for powering low-voltage microprocessors, or
Features
• Dual 1.5A, Synchronous Step-down Converters and Dual
300mA, General-purpose LDOs
applications using a single Li-Ion or Li-Polymer cell battery to
power multiple voltage rails. The ISL9305H integrates two
high-efficiency 3MHz synchronous step-down converters (DCD1
and DCD2) and two low-input, low-dropout linear regulators
(LDO1 and LDO2).
• Input Voltage Range
- DCD1/DCD2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5V to 5.5V
- LDO1/LDO2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.5V to 5.5V
The 3MHz PWM switching frequency allows the use of very
small external inductors and capacitors. Both step-down
converters can enter skip mode under light load conditions to
further improve the efficiency and maximize the battery life.
For noise sensitive applications, they can also be programmed
2
• 400kb/s I C-Bus Series Interface Transfers the Control Data
Between the Host Controller and the ISL9305H
• Adjustable Output Voltage
- VODCD1/VODCD2 . . . . . . . . . . . . . . . . . . . . . . . . 0.8V to V
IN
2
through I C interface to operate in forced PWM mode
2
• Fixed Output I C Programmability
2
regardless of the load current condition. The I C interface
- At 25mV/Step . . . . . . . . . . . . . . . . . . . . . . . .0.825V to 3.6V
supports on-the-fly slew rate control of the output voltage from
0.825V to 3.6V at 25mV/step size for dynamic power saving.
Each step-down converter can supply up to 1.5A load current.
The default output voltage can be set from 0.8V to VIN using
external feedback resistors on the adjustable version, or the
ISL9305H can be ordered in factory pre-set voltage options
from 0.9V to 3.6V in 50mV step.
2
• LDO1/LDO2 Output Voltage I C Programmability
- At 50mV/Step . . . . . . . . . . . . . . . . . . . . . . . . . . 0.9V to 3.6V
• 50μA I (Typ) with DCD1/DCD2 in Skip Mode; 20μA I (Typ)
for Each Enabled LDO
Q
Q
2
• On-the-fly I C Programming of DC/DC and LDO Output
Voltages
The ISL9305H also provides two 300mA low dropout (LDO)
regulators. The input voltage range is 1.5V to 5.5V allowing them
to be powered from one of the on-chip step-down converters or
directly from the battery. The default LDO output comes with
factory pre-set fixed output voltage options between 0.9V to 3.3V.
2
• DCD1/DCD2 I C Programmable Skip Mode Under Light
Load or Forced Fixed Switching Frequency PWM Mode
• Small, Thin 4mmx4mm TQFN Package
Applications
The ISL9305H is available in a 4mmx4mm 16 Ld TQFN package.
• Cellular Phones, Smart Phones
Related Literature
• FN7605, ISL9305 Data Sheet
• PDAs, Portable Media Players, Portable Instruments
• Single Li-Ion/Li-Polymer Battery-Powered Equipment
• DSP Core Power
• AN1564 “ISL9305 and ISL9305H Evaluation Boards”
L
= 1.5µH
R
1
1.5A
PG
SW1
FB1
2.5V TO 5.5V
VINDCD1
*
C
1
4
R
R
2
VINDCD2
10µF
C
10µF
10
L
= 1.5µH
R
2
1.5A
SDAT
SCLK
SW2
FB2
ISL9305H
*
C
5
10µF
1.5V TO 5.5V
1.5V TO 5.5V
3
VINLDO1
4
C
1µF
2
300mA
300mA
VOLDO1
VOLDO2
VINLDO2
C
1µF
3
C
1µF
C
7
1µF
6
GNDDCD1 GNDDCD2 GNDLDO
*Only for adjustable output version. For fixed output version, directly
connect the FB pin to the output of the buck converter.
FIGURE 1. TYPICAL APPLICATION DIAGRAM
FN7724 Rev 2.00
March 7, 2014
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