isl91127

DATA SHORT
To request the full datasheet, please visit www.intersil.com/products/ISL91127
High Efficiency Buck-Boost Regulator with 4.5A Switches
ISL91127
Features
The ISL91127 is a high-current buck-boost switching regulator
for systems using new battery chemistries. It uses Intersil’s
proprietary buck-boost algorithm to maintain voltage
regulation while providing excellent efficiency and very low
output voltage ripple when the input voltage is close to the
output voltage.
• Accepts input voltages above or below regulated output
voltage
The ISL91127 is capable of delivering at least 2.1A continuous
output current (VOUT = 3.3V) over a battery voltage range of
2.5V to 4.35V. This maximizes the energy utilization of
advanced single-cell Li-ion battery chemistries that have
significant capacity left at voltages below the system voltage.
Its fully synchronous low ON-resistance 4-switch architecture
and a low quiescent current of only 30µA optimize efficiency
under all load conditions.
The ISL91127 supports standalone applications with a fixed
3.3V or 3.5V output voltage or adjustable output voltage with
an external resistor divider. Output voltages as low as 1V or as
high as 5.2V are supported.
The ISL91127 is available in a 20 bump, 0.4mm pitch WLCSP
(2.15mmx1.74mm) with a 2.5MHz switching frequency, which
further reduces the size of external components.
• Automatic and seamless transitions between buck and
boost modes
• Input voltage range: 1.8V to 5.5V
• Output current: up to 2.1A (PVIN = 2.5V, VOUT = 3.3V)
• Burst current: up to 3A (PVIN = 3V, VOUT = 3.3V,
tON < 600µs, t = 4.6ms)
• High efficiency: up to 96%
• 30µA quiescent current maximizes light-load efficiency
• 2.5MHz switching frequency minimizes external component
size
• Fully protected for short-circuit, over-temperature and
undervoltage
• Small 2.15mmx1.74mm WLCSP
Applications
• Brownout-free system voltage for smartphones and tablet
PCs
Related Literature
• Wireless communication devices
• UG045, “ISL91127IIx-EVZ Evaluation Boards User Guide”
• 2G/3G/4G RF power amplifiers
100
VIN = 3.6V
VIN = 4V
IS L 9 1 1 2 7 IIN Z
V IN = 1 . 8 V T O 5 .5 V
LX1
P V IN
C1
10µF
L1
1µH
LX2
V IN
VOUT
EN
FB
PGND
SGND
MODE
V O U T = 3 .3 V
C2
2x22µF
EFFICIENCY (%)
95
90
85
VIN = 3.3V
VIN = 3V
VIN = 2.5V
80
75
1
10
100
100 0
LOAD CURREN T (mA)
FIGURE 1. TYPICAL APPLICATION: VOUT = 3.3V
April 5, 2016
FN8418.0
1
FIGURE 2. EFFICIENCY: VOUT = 3.3V
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 1-888-468-3774 | Copyright Intersil Americas LLC 2016. All Rights Reserved
Intersil (and design) is a trademark owned by Intersil Corporation or one of its subsidiaries.
All other trademarks mentioned are the property of their respective owners.
ISL91127
For additional products, see www.intersil.com/en/products.html
Intersil products are manufactured, assembled and tested utilizing ISO9001 quality systems as noted
in the quality certifications found at www.intersil.com/en/support/qualandreliability.html
Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time
without notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be
accurate and reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third
parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries.
For information regarding Intersil Corporation and its products, see www.intersil.com
Submit Document Feedback
2
FN8418.0
April 5, 2016