DATASHEET
ISL9111, ISL9111A
Low Input Voltage, High Efficiency Synchronous Boost Converter with 1A Switch
FN7602
Rev.4.00
Jun 4, 2012
The ISL9111 and ISL9111A provide a power supply solution
Features
for single-cell, dual-cell, or three-cell alkaline, NiCd or NiMH
• Up to 97% Efficiency at Typical Operating Conditions
battery-powered applications. The device has a typical 0.8V
start-up voltage and is capable of supplying up to 5.25V output
voltage. Both devices are guaranteed to supply 100mA from a
single-cell input and 240mA from a dual-cell input when
output is 3.3V. High 1.2MHz switching frequency allows for the
use of tiny, low-profile inductors and ceramic capacitors to
minimize the size of the solution.
• Minimum Start-up Voltage
- 0.8V (ISL9111)
- 0.6V (ISL9111A)
• Minimum Operating Voltage
- 0.7V (ISL9111)
- 0.5V (ISL9111A)
The ISL9111 and ISL9111A are internally compensated, fully
integrated synchronous boost converters optimized for
efficiency with minimal external components. At light load, the
device enters skip mode and consumes only 20µA of
quiescent current, resulting in higher efficiency at light loads
and maximum battery life.
• Low Quiescent Current: 20μA (Typical)
• At VOUT = 3.3V
- 100mA Output Current @ VIN = 0.9V
- 240mA Output from @ VIN = 1.8V
The ISL9111 and ISL9111A address both rechargeable and
non-rechargeable battery applications. The ISL9111 has a
UVLO feature, which will internally shut off at 0.7V protecting a
rechargeable battery. The ISL9111A has this feature disabled
to maximize the usable life of a non-rechargeable single cell
battery. The parts are available in fixed 3.0V, 3.3V and 5.0V
output voltage versions or an adjustable output voltage version
(ADJ). The fixed output voltage version also provides a FAULT
pin for fault condition monitoring. The ISL9111 and ISL9111A
are available in a 6 Ld SOT-23 package.
• Logic Control Shutdown (Iq < 1µA)
• Output Voltage Up to 5.25V
• Output Disconnect During Shutdown
• Skip Mode Under Light Load Condition
• Undervoltage Lockout (ISL9111 Only)
• Fault Protection: OVP (ADJ Version Only), OTP, Short Circuit
• 6 Ld SOT-23 Package
Applications
• Products Including Portable HDMI and USB-OTG
• Personal Medical Products
• Wireless Mouse/Keyboard
• Bluetooth Headsets
• MP3/MP4 Players/DSC
• Single-cell, Dual-cell and Triple-cell Alkaline, NiCd, NiMH
Powered Products
100
4.7µH
V
= 3.6V
IN
95
90
85
80
75
70
65
60
55
50
1
SW
VOUT
5
2
VOUT
GND
6
3
VIN
VIN
EN
4.7µF
4.7µF
V
= 0.9V
IN
V
= 1.8V
IN
VFLT
1k
4
FAULT
ISL9111: 3.0/3.3/5.0V, ISL9111A: 3.0/3.3/5.0V
0.1
1
10
(mA)
100
1000
I
OUT
FIGURE 1. TYPICAL APPLICATION
FIGURE 2. FIXED 5V EFFICIENCY
FN7602 Rev.4.00
Jun 4, 2012
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