DATASHEET
ISL9104, ISL9104A
500mA 4.3MHz Low I
Q
High Efficiency Synchronous Buck Converter
The ISL9104, ISL9104A is a 500mA, 4.3MHz step-down
regulator, which is ideal for powering low-voltage
microprocessors in compact devices such as PDAs and cellular
phones. It is optimized for generating low output voltages
down to 0.8V. The supply voltage range is from 2.7V to 6V
allowing the use of a single Li+ cell, three NiMH cells or a
regulated 5V input. It has guaranteed minimum output current
of 500mA. A high switching frequency of 4.3MHz pulse-width
modulation (PWM) allows using small external components.
Under light load condition, the device operates at low I
Q
skip
mode with typical 20µA quiescent current for highest light
load efficiency to maximize battery life, and it automatically
switches to fixed frequency PWM mode under heavy load
condition.
The ISL9104, ISL9104A includes a pair of low ON-resistance
P-Channel and N-Channel internal MOSFETs to maximize
system efficiency and minimize the external component count.
100% duty-cycle operation allows less than 300mV dropout
voltage at 500mA.
The ISL9104, ISL9104A offers internal digital soft-start,
enable for power sequence, overcurrent protection and
thermal shutdown functions. In addition, the ISL9104,
ISL9104A offers a quick bleeding function that discharges the
output capacitor when the IC is disabled.
The ISL9104, ISL9104A is offered in a 1.6x1.6mm µTDFN
package. The complete converter occupies less than 0.5CM
2
.
FN6829
Rev 5.00
Features
• High Efficiency Integrated Synchronous Buck Regulator with
up to 93% Efficiency
• 2.7V to 6.0V Supply Voltage
• 4.3MHz PWM Switching Frequency
• 500mA Guaranteed Output Current
• 3% Output Accuracy Over-Temperature and Line for Fixed
Output Options
• 20µA Quiescent Supply Current in Skip Mode
• Less than 1µA Logic Controlled Shutdown Current
• 100% Maximum Duty Cycle for Lowest Dropout
• Ultrasonic Switching Frequency at Skip Mode to Prevent
Audible Frequency Noise (For ISL9104A Only)
• Discharge Output Capacitor when Disabled
• Internal Digital Soft-Start
• Peak Current Limiting, Short Circuit Protection
• Over-Temperature Protection
• Chip Enable
• Small 6 Pin 1.6mmx1.6mm µTDFN Package
• Pb-Free (RoHS Compliant)
Applications
• Single Li-ion Battery-Powered Equipment
• Mobile Phones and MP3 Players
• PDAs and Palmtops
• WCDMA Handsets
• Portable Instruments
Related Literature
• See
AN1522,
“ISL9104xxxxEVAL1Z, ISL9104AxxxxEVAL1Z
Evaluation Board Application Manual”
Pin Configuration
EFFICIENCY (%)
100
95
90
85
80
75
70
65
60
55
50
1
10
I
OUT
(mA)
100
V
IN
= 2.7V
V
OUT
= 1.8V
L = 1µH
1000
ISL9104, ISL9104A
(6 LD 1.6x1.6 µTDFN)
TOP VIEW
VIN 1
EN 2
NC 3
6 SW
5 GND
4 FB
FIGURE 1. EFFICIENCY vs OUTPUT CURRENT
FN6829 Rev 5.00
Page 1 of 14
ISL9104, ISL9104A
Pin Descriptions
PIN NUMBER
1
2
3
4
PIN NAME
VIN
EN
NC
FB
DESCRIPTION
Input supply voltage. Typically connect a 10µF ceramic capacitor to ground.
Regulator enable pin. Enable the device when driven to high. Shut down the chip and discharge
output capacitor when driven to low. Do not leave this pin floating.
No connect; leave floating.
Buck converter output feedback pin. For adjustable output version, its typical value is 0.8V and
connect it to the output through a resistor divider for desired output voltage; for fixed output version,
directly connect this pin to the converter output.
Ground connection.
Switching node connection. Connect to one terminal of inductor.
5
6
GND
SW
Typical Applications
ISL9104, ISL9104A ADJUSTABLE OUTPUT
L
1.0µH
VIN
C1
4.7µF
SW
C2
4.7µF
OUTPUT
UP TO 500mA
INPUT: 2.7V TO 6V
R1
100k
C3
47pF
ENABLE
EN
DISABLE
GND
FB
R2
100k
ISL9104, ISL9104A FIXED OUTPUT
OUTPUT
UP TO 500mA
INPUT: 2.7V TO 6V
L
1.0µH
VIN
SW
C2
4.7µF
C1
4.7µ F
ENABLE
EN
DISABLE
FB
GND
FIGURE 2. TYPICAL APPLICATIONS DIAGRAM
Note: For adjustable output version, the internal feedback resistor divider is disabled and the FB pin is directly connected to the error
amplifier.
FN6829 Rev 5.00
Page 2 of 14
ISL9104, ISL9104A
PARTS
L
C1, C2
C3
R1, R2
DESCRIPTION
Inductor
Input and output
capacitor
Capacitor
Resistor
MANUFACTURERS
KEMET
Murata
KEMET
Various
PART NUMBER
LB3218-T1R0MK
GRM188R60J475KE19D
C0402C470J5GACTU
-
SPECIFICATIONS
1.0µH/1.0A/60m
4.7µF/6.3V, X5R
47pF/50V
100kSMD, 1%
0603
0402
0402
SIZE
3.2mmx1.8mmx1.8mm
Ordering Information
PART NUMBER
(Notes 1, 3, 4)
ISL9104IRUNZ-T
ISL9104IRUJZ-T
ISL9104IRUFZ-T
ISL9104IRUDZ-T
ISL9104IRUCZ-T
ISL9104IRUBZ-T
ISL9104IRUWZ-T
ISL9104IRUAZ-T
ISL9104AIRUNZ-T
ISL9104AIRUJZ-T
ISL9104AIRUFZ-T
ISL9104AIRUDZ-T
ISL9104AIRUCZ-T
ISL9104AIRUBZ-T
ISL9104AIRUWZ-T
ISL9104AIRUAZ-T
ISL9104AIRUAEVAL1Z
ISL9104AIRUBEVAL1Z
ISL9104AIRUCEVAL1Z
ISL9104AIRUDEVAL1Z
ISL9104AIRUFEVAL1Z
ISL9104AIRUJEVAL1Z
ISL9104AIRUNEVAL1Z
ISL9104AIRUWEVAL1Z
ISL9104IRUAEVAL1Z
ISL9104IRUBEVAL1Z
ISL9104IRUCEVAL1Z
ISL9104IRUDEVAL1Z
ISL9104IRUFEVAL1Z
ISL9104IRUJEVAL1Z
ISL9104IRUNEVAL1Z
ISL9104IRUWEVAL1Z
NOTES:
1. Please refer to
TB347
for details on reel specifications.
2. Other output voltage options may be available upon request, please contact Intersil for more details.
3. These Intersil Pb-free plastic packaged products employ special Pb-free material sets; molding compounds/die attach materials and NiPdAu plate -
e4 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.
4. For Moisture Sensitivity Level (MSL), please see device information page for
ISL9104, ISL9104A.
For more information on MSL please see techbrief
TB363.
PART
MARKING
K6
K7
K8
K9
L0
L1
L2
L3
L4
L5
L6
L7
L8
L9
M0
M1
Evaluation Board
Evaluation Board
Evaluation Board
Evaluation Board
Evaluation Board
Evaluation Board
Evaluation Board
Evaluation Board
Evaluation Board
Evaluation Board
Evaluation Board
Evaluation Board
Evaluation Board
Evaluation Board
Evaluation Board
Evaluation Board
OUTPUT VOLTAGE
(V) (Note 2)
3.3
2.8
2.5
2.0
1.8
1.5
1.2
ADJ
3.3
2.8
2.5
2.0
1.8
1.5
1.2
ADJ
ULTRASONIC
FUNCTION
NO
NO
NO
NO
NO
NO
NO
NO
YES
YES
YES
YES
YES
YES
YES
YES
TEMP RANGE
(°C)
-40 to +85
-40 to +85
-40 to +85
-40 to +85
-40 to +85
-40 to +85
-40 to +85
-40 to +85
-40 to +85
-40 to +85
-40 to +85
-40 to +85
-40 to +85
-40 to +85
-40 to +85
-40 to +85
PACKAGE
Tape and Reel
(Pb-Free)
6 Ld µTDFN
6 Ld µTDFN
6 Ld µTDFN
6 Ld µTDFN
6 Ld µTDFN
6 Ld µTDFN
6 Ld µTDFN
6 Ld µTDFN
6 Ld µTDFN
6 Ld µTDFN
6 Ld µTDFN
6 Ld µTDFN
6 Ld µTDFN
6 Ld µTDFN
6 Ld µTDFN
6 Ld µTDFN
PKG
DWG. #
L6.1.6x1.6
L6.1.6x1.6
L6.1.6x1.6
L6.1.6x1.6
L6.1.6x1.6
L6.1.6x1.6
L6.1.6x1.6
L6.1.6x1.6
L6.1.6x1.6
L6.1.6x1.6
L6.1.6x1.6
L6.1.6x1.6
L6.1.6x1.6
L6.1.6x1.6
L6.1.6x1.6
L6.1.6x1.6
FN6829 Rev 5.00
Page 3 of 14
ISL9104, ISL9104A
Absolute Maximum Ratings
VIN, EN to GND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SW to GND. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
FB to GND (for adjustable version) . . . . . . . . . . . . . . . . . . . . . .
FB to GND (for fixed output version). . . . . . . . . . . . . . . . . . . . .
-0.3V to 6.5V
-1.5V to 6.5V
-0.3V to 2.7V
-0.3V to 3.6V
Thermal Information
Thermal Resistance (Typical, Note 5)
JA
(°C/W)
1.6x1.6 µTDFN Package . . . . . . . . . . . . . . . . . . . . . . . . .
160
Junction Temperature Range . . . . . . . . . . . . . . . . . . . . . . .-40°C to +125°C
Storage Temperature Range. . . . . . . . . . . . . . . . . . . . . . . .-65°C to +150°C
Pb-free Reflow Profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . see link below
http://www.intersil.com/pbfree/Pb-FreeReflow.asp
Recommended Operating Conditions
VIN Supply Voltage Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.7V to 6.0V
Load Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . up to 500mA
Ambient Temperature Range . . . . . . . . . . . . . . . . . . . . . . . . -40°C to +85°C
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.
NOTE:
5.
JA
is measured with the component mounted on a high effective thermal conductivity test board in free air. See Tech Brief TB379 for details.
Electrical Specifications
Unless otherwise noted, all parameter limits are guaranteed over the recommended operating
conditions and the typical specifications are measured at the following conditions: T
A
= +25°C, V
IN
= V
EN
= 3.6V, L = 1.0µH, C
1
= 4.7µF,
C
2
= 4.7µF, I
OUT
= 0A (see “Typical Applications” on page 2). Boldface limits apply over the operating temperature range,
-40°C to +85°C.
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
(Note 6)
TYP
MAX
(Note 6)
UNITS
SUPPLY
Undervoltage Lockout Threshold (UVLO)
UVLO Hysteresis
Quiescent Supply Current (for ISL9104
adjustable output voltage only)
Quiescent Supply Current (for ISL9104A
adjustable output only)
Quiescent Supply Current (for ISL9104A 1.5V
fixed output)
Shut Down Supply Current
I
SD
I
VIN1
I
VIN2
In skip mode, no load at the output, no switch,
V
IN
= 6.0V
In skip mode, no load at the output, no switch,
V
IN
= 6.0V
In skip mode, no load at the output, V
IN
= 6.0V
V
IN
= 6.0V, EN = LOW
V
UVLO
T
A
= +25°C,
Rising
-
50
-
-
-
-
2.5
150
20
32
84
0.05
2.7
-
34
45
-
1
V
mV
µA
µA
µA
µA
OUTPUT REGULATION
FB Voltage Accuracy (for adjustable output only)
T
A
= 0°C to +85°C
-2
-2.5
-
-
0.8
+2
+2.5
%
%
V
FB Voltage
FB Bias Current (for adjustable output only)
Output Voltage Accuracy (for fixed output
voltage only)
Line Regulation
Load Regulation
SW
P-Channel MOSFET ON-Resistance
V
FB
I
FB
VFB = 0.75V
-
-3
-
-
5
-
0.2
0.0009
100
3
-
-
nA
%
%/V
%/mA
PWM Mode
V
IN
= V
O
+ 0.5V to 6V (minimal 2.7V)
V
IN
=3.6V, I
O
= 150mA to 500mA
V
IN
= 3.6V, I
O
= 200mA
V
IN
= 2.7V, I
O
= 200mA
-
-
-
-
-
0.45
0.55
0.4
0.5
100
1.00
100
0.6
0.72
0.52
0.65
-
1.35
-
A
%
N-Channel MOSFET ON-Resistance
V
IN
= 3.6V, I
O
= 200mA
V
IN
= 2.7V, I
O
= 200mA
N-Channel Bleeding MOSFET ON-Resistance
P-Channel MOSFET Peak Current Limit
Maximum Duty Cycle
I
PK
V
IN
= 4.2V
0.75
-
FN6829 Rev 5.00
Page 4 of 14
ISL9104, ISL9104A
Unless otherwise noted, all parameter limits are guaranteed over the recommended operating
conditions and the typical specifications are measured at the following conditions: T
A
= +25°C, V
IN
= V
EN
= 3.6V, L = 1.0µH, C
1
= 4.7µF,
C
2
= 4.7µF, I
OUT
= 0A (see “Typical Applications” on page 2). Boldface limits apply over the operating temperature range,
-40°C to +85°C. (Continued)
PARAMETER
SW Leakage Current
PWM Switching Frequency
SW Minimum On-Time
Soft-Start-Up Time
f
S
SYMBOL
TEST CONDITIONS
SW at Hi-Z state
V
IN
= 3.6V, T
A
= -20°C to +85°C
MIN
(Note 6)
-
3.6
-
-
TYP
0.01
4.3
65
1.0
MAX
(Note 6)
2
4.9
-
-
UNITS
µA
MHz
ns
ms
Electrical Specifications
EN
Logic Input Low
Logic Input High
Logic Input Leakage Current
Thermal Shutdown
Thermal Shutdown Hysteresis
-
1.4
-
-
-
-
-
0.1
130
30
0.4
-
1
-
-
V
V
µA
°C
°C
NOTE:
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.
Typical Operating Performance
100
90
80
EFFICIENCY (%)
EFFICIENCY (%)
70
60
50
40
30
20
10
0
0
0.1
0.2
0.3
LOAD CURRENT (A)
0.4
0.5
V
IN
= 3.8V
V
IN
= 4.9V
V
IN
= 2.7V
100
90
80
70
60
50
40
30
20
10
0
0
0.1
0.2
0.3
LOAD CURRENT (A)
0.4
0.5
V
IN
= 3.5V
V
IN
= 4.5V
V
IN
= 5.5V
FIGURE 3. EFFICIENCY vs LOAD CURRENT (V
OUT
= 1.5V)
FIGURE 4. EFFICIENCY vs LOAD CURRENT (V
OUT
= 2.5V)
30
QUIESCENT CURRENT (µA)
1.630
1.625
25
T = +85°C
T = +25°C
V
O
(V)
1.620
1.615
1.610
LOAD CURRENT RISING
20
15
1.605
T = -45°C
10
2.70
3.25
3.80
4.35
4.90
5.45
6.00
1.600
0
100
LOAD CURRENT FALLING
INPUT VOLTAGE (V)
200
300
I
OUT
(mA)
400
500
FIGURE 5. INPUT QUIESCENT CURRENT vs V
IN
(V
OUT
= 2.5V)
FIGURE 6. OUTPUT VOLTAGE vs LOAD CURRENT (V
IN
= 3.6V,
V
OUT
= 1.6V)
FN6829 Rev 5.00
Page 5 of 14
