DATASHEET
ISL9120IR
Compact High Efficiency Low Power Buck-Boost Regulator
The
ISL9120IR
is a highly integrated buck-boost switching
regulator that accepts input voltages either above or below the
regulated output voltage. This regulator automatically
transitions between buck and boost modes without significant
output disturbance. The ISL9120IR also has automatic bypass
functionality for when the input voltage is generally within 1%
to 2% of the output voltage, there will be a direct bypass
connection between the VIN and VOUT pins. In addition to the
automatic bypass functionality, the ISL9120IR also has a
forced bypass functionality with the use of the BYPS pin.
This device is capable of delivering up to 800mA of output
current (V
IN
= 2.5V, V
OUT
= 3.3V) and provides excellent
efficiency due to its adaptive current limit pulse frequency
modulation (PFM) control architecture.
The ISL9120IR is designed for stand-alone applications and
supports a 3.3V fixed output voltage or variable output
voltages with an external resistor divider. The forced bypass
power saving mode can be chosen if voltage regulation is not
required. The device consumes less than 3.5µA of current over
the operating temperature range in the forced bypass mode.
The ISL9120IR requires only a single inductor and very few
external components. Power supply solution size is minimized
by a 3mmx3mm 12 Ld TQFN package.
FN8743
Rev 1.00
February 2, 2016
Features
• Accepts input voltages above or below regulated output
voltage
• Automatic bypass mode functionality
• Automatic and seamless transitions between buck and
boost modes
• Input voltage range: 1.8V to 5.5V
• Selectable forced bypass power saving mode
• Adaptive multilevel current limit scheme to optimize
efficiency at low and high currents
• Output current: up to 800mA (V
IN
= 2.5V, V
OUT
= 3.3V)
• High efficiency: up to 98%
• 41µA quiescent current maximizes light-load efficiency
• Fully protected for over-temperature and undervoltage
• Small 3mmx3mm 12 Ld TQFN package
Applications
• Smartphones and tablets
• Portable consumer and wearable devices
V
IN
=
1.8V TO 5.5V
C
1
10µF
ENABLE
DISABLE
BYPASS
BUCK-BOOST
100
ISL9120IRNZ
VIN
95
V
IN
= 3.6V
LX1
EN
BYPS
LX2
VOUT
FB
PGND
EFFICIENCY (%)
L
1
1µH
90
V
IN
= 4V
85
V
IN
= 3.4V
80
75
70
V
IN
= 2.5V
V
IN
= 3V
V
OUT
= 3.3V
C
2
22µF or 47µF
GND
1
10
100
OUTPUT CURRENT (mA)
1000
FIGURE 1. TYPICAL FIXED OUTPUT APPLICATION
FIGURE 2. EFFICIENCY: V
OUT
= 3.3V, T
A
= +25°C
FN8743 Rev 1.00
February 2, 2016
Page 1 of 13
ISL9120IR
Block Diagram
LX1
A1
LX2
C1
VIN
A2
V
REF
+
REVERSE
CURRENT
GATE DRIVERS
AT ANTI-
SHOOT THRU
-
SOFT
DIS CHARGE
C2
VOUT
EN
EN
PVIN
MONITOR
THE RMAL
SHUTDOWN
B1 PGND
VOUT
CLAMP
PFM CONTROL
CURRENT
DETECT
EN B2
BYPS A3
VOLTAGE
COMPARATOR
-
EN
C3
VREF
FB
+
+
ILIM
VOLTAGE
PROG.
-
CURRENT
COMPARATOR
B3
GND
FIGURE 3. BLOCK DIAGRAM
Pin Configuration
ISL9120IR
(12 LD 3x3 TQFN)
TOP VIEW
11
VOUT
12
LX2
10
FB
Pin Descriptions
PIN NUMBER
1, 12
2
3, 4
PIN NAME
LX2
PGND
LX1
VIN
BYPS
GND
EN
FB
VOUT
DESCRIPTION
Inductor connection, output side.
Power ground for high switching current.
Inductor connection, input side.
Power supply input. Range: 1.8V to 5.5V.
Connect 1x 10µF capacitor to PGND.
Bypass mode enable pin. HIGH for bypass
mode. LOW for buck-boost mode.
Analog ground pin.
Logic input, drive HIGH to enable device.
Voltage feedback pin.
Buck-boost output. Connect 22µF or 47µF
capacitor to PGND.
LX2
1
PGND
2
LX1
3
LX1
4
VIN
5
VIN
6
9
EN
EPAD
8
GND
7
BYPS
5, 6
7
8
9
10
11
FN8743 Rev 1.00
February 2, 2016
Page 2 of 13
ISL9120IR
Ordering Information
PART NUMBER
(Notes
1, 2, 3)
ISL9120IRTAZ
ISL9120IRTNZ
ISL9120IRN-EVZ
ISL9120IRA-EVZ
NOTES:
1. Add “-T*” suffix for 3k unit tape and reel. Please refer to
TB347
for details on reel specifications.
2. These Intersil Pb-free plastic packaged products employ special Pb-free material sets, molding compounds/die attach materials, and 100% matte
tin plate plus anneal (e3 termination finish, which is RoHS compliant and compatible with both SnPb and Pb-free soldering operations). Intersil
Pb-free products are MSL classified at Pb-free peak reflow temperatures that meet or exceed the Pb-free requirements of IPC/JEDEC J STD-020.
3. For Moisture Sensitivity Level (MSL), please see product information page for
ISL9120.
For more information on MSL, please see tech brief
TB363.
PART
MARKING
120A
120N
VOUT
(V)
ADJ.
3.3
TEMP RANGE
(°C)
-40 to +85
-40 to +85
PACKAGE
(RoHS Compliant)
12 Ld 3x3 TQFN
12 Ld 3x3 TQFN
PKG.
DWG. #
L12.3x3A
L12.3x3A
Evaluation Board for ISL9120IRNZ
Evaluation Board for ISL9120IRAZ
FIGURE 4.
KEY DIFFERENCES BETWEEN FAMILY OF PARTS
ISL9120
Buck-boost
regulation
Bypass
Package
Yes
Yes
1.41x1.41mm 9-Bump
WLCSP
Yes
Yes
3x3mm 12Ld TQFN
ISL9120IR
FN8743 Rev 1.00
February 2, 2016
Page 3 of 13
ISL9120IR
Absolute Maximum Ratings
VIN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 6.5V
LX1, LX2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 6.5V
FB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 6.5V
GND, PGND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 0.3V
All Other Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 6.5V
ESD Rating
Human Body Model (Tested per JESD22-A114F) . . . . . . . . . . . . . . .2.5kV
Machine Model (Tested per JESD22-A115C) . . . . . . . . . . . . . . . . . 200V
Charged Device Model (Tested per JESD22-C101F). . . . . . . . . . . . . . 2kV
Latch-Up (Tested per JESD78D; Class 2) . . . . . . . . . . . . . . . . . . . . . . 100mA
Thermal Information
Thermal Resistance (Typical)
JA
(°C/W)
JC
(°C/W)
3x3 TQFN (Notes
4, 5)
. . . . . . . . . . . . . . . . .
55
5
Maximum Junction Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . .+125°C
Storage Temperature Range. . . . . . . . . . . . . . . . . . . . . . . .-65°C to +150°C
Pb-Free Reflow Profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . see
TB493
Recommended Operating Conditions
Temperature Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -40°C to +85°C
Supply Voltage (V
IN
) Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.8V to 5.5V
Load Current (I
OUT
) Range (DC) . . . . . . . . . . . . . . . . . . . . . . . . 0A to 800mA
CAUTION: Do not operate at or near the maximum ratings listed for extended periods of time. Exposure to such conditions may adversely impact product
reliability and result in failures not covered by warranty.
NOTES:
4.
JA
is measured in free air with the component mounted on a high effective thermal conductivity test board with “direct attach” features. See Tech
Brief
TB379.
5. For
JC
, the “case temp” location is the center of the exposed metal pad on the package underside.
Analog Specifications
V
IN
= V
EN
= 3.6V, V
OUT
= 3.3V, L
1
= 1µH, C
1
= 10µF, C
2
= 47µF, T
A
= +25°C. Boldface limits apply across the
recommended operating temperature range, -40°C to +85°C and input voltage range (1.8V to 5.5V).
SYMBOL
POWER SUPPLY
V
IN
V
UVLO
Input Voltage Range
V
IN
Undervoltage Lockout Threshold
Rising
Falling
I
VIN
I
SD
I
BYP
VIN Supply Current
VIN Supply Current, Shutdown
VIN Supply Current, Bypass Mode
V
OUT
= 3.7V (Note
7)
EN = GND
BYPS = Logic High, V
IN
≤5V
1.550
1.8
1.725
1.650
41
0.005
0.8
55
1
3.5
5.5
1.790
V
V
V
µA
µA
µA
PARAMETER
TEST CONDITIONS
MIN
(Note
6)
TYP
MAX
(Note
6)
UNIT
OUTPUT VOLTAGE REGULATION
V
OUT
Output Voltage Range
Output Voltage Accuracy
V
FB
I
FB
V
OUT
/V
IN
FB Pin Voltage Regulation
FB Pin Bias Current
Line Regulation, 500mA
ISL9120IRAZ, I
OUT
= 100mA
V
IN
= 3.7V, I
OUT
= 1mA
For adjustable output version (ISL9120IRAZ)
For adjustable output version (ISL9120IRAZ)
I
OUT
= 500mA, V
OUT
= 3.3V, V
IN
step from 2.3V to
5.5V
V
IN
= 3.7V, V
OUT
= 3.3V, I
OUT
step from 0mA to
500mA
I
OUT
= 100mA, V
OUT
= 3.3V, V
IN
step from 2.3V to
5.5V
V
IN
= 3.7V, V
OUT
= 3.3V, I
OUT
step from 0mA to
100mA
Rising
5.32
400
0.00681
0.0072
0.00273
0.05
5.82
1.00
-3
0.80
0.025
5.20
+4
V
%
V
µA
mV/mV
mV/mA
mV/mV
mV/mA
V
mV
V
OUT
/I
OUT
Load Regulation, 500mA
V
OUT
/V
I
Line Regulation, 100mA
V
OUT
/I
OUT
Load Regulation, 100mA
V
CLAMP
Output Voltage Clamp
Output Voltage Clamp Hysteresis
DC/DC SWITCHING SPECIFICATIONS
I
PFETLEAK
I
NFETLEAK
LX1 Pin Leakage Current
LX2 Pin Leakage Current
-0.05
V
IN
= 3.6V
-0.05
+0.05
+0.05
µA
µA
FN8743 Rev 1.00
February 2, 2016
Page 4 of 13
ISL9120IR
V
IN
= V
EN
= 3.6V, V
OUT
= 3.3V, L
1
= 1µH, C
1
= 10µF, C
2
= 47µF, T
A
= +25°C. Boldface limits apply across the
recommended operating temperature range, -40°C to +85°C and input voltage range (1.8V to 5.5V). (Continued)
SYMBOL
PARAMETER
TEST CONDITIONS
MIN
(Note
6)
TYP
MAX
(Note
6)
UNIT
Analog Specifications
SOFT-START AND SOFT DISCHARGE
t
SS
Soft-Start Time
Time from when EN signal asserts to when output
voltage ramp starts.
Time from when output voltage ramp starts to when
output voltage reaches 95% of its nominal value
with device operating in buck mode.
V
IN
= 4V, I
OUT
= 500mA
Time from when output voltage ramp starts to when
output voltage reaches 95% of its nominal value
with device operating in boost mode.
V
IN
= 3V, I
OUT
= 500mA
r
DISCHG
V
OUT
Soft-Discharge ON-Resistance
EN < V
IL
1
1
ms
ms
1
ms
110
Ω
POWER MOSFET
r
DSON_P
r
DSON_N
P-Channel MOSFET ON-Resistance
N-Channel MOSFET ON-Resistance
I
OUT
= 200mA, measured with internal test mode
I
OUT
= 200mA, measured with internal test mode
63
63
mΩ
mΩ
INDUCTOR PEAK CURRENT LIMIT
I
LIM_MAX
Maximum Peak Current Limit
2
A
THERMAL PROTECTION
Thermal Shutdown
Thermal Shutdown Hysteresis
LOGIC INPUTS
I
LEAK
V
IH
V
IL
NOTES:
6. Parameters with MIN and/or MAX limits are 100% tested at +25°C, unless otherwise specified. Temperature limits established by characterization
and are not production tested.
7. Quiescent current measurements are taken when the output is not switching.
Input Leakage
Input HIGH Voltage
Input LOW Voltage
1.4
0.4
0.013
0.500
µA
V
V
150
35
°C
°C
FN8743 Rev 1.00
February 2, 2016
Page 5 of 13