NOT RECOMMENDED FOR NEW DESIGNS
USE ISL6443A
DATASHEET
FN9044
Rev 2.00
Aug 9, 2006
ISL6443
300kHz Dual, 180° Out-of-Phase, Step-Down PWM and Single Linear Controller
The ISL6443 is a high-performance, triple-output controller
optimized for converting wall adapter, battery or network
intermediate bus DC input supplies into the system supply
voltages required for a wide variety of applications. Each
output is adjustable down to 0.8V. The two PWMs are
synchronized 180° out of phase reducing the RMS input
current and ripple voltage.
The ISL6443 incorporates several protection features. An
adjustable overcurrent protection circuit monitors the output
current by sensing the voltage drop across the lower
MOSFET. Hiccup mode overcurrent operation protects the
DC/DC components from damage during output
overload/short circuit conditions. Each PWM has an
independent logic-level shutdown input (SD1 and SD2).
A single PGOOD signal is issued when soft-start is complete
on both PWM controllers and their outputs are within 10% of
the set point and the linear regulator output is greater than
75% of its setpoint. Thermal shutdown circuitry turns off the
device if the junction temperature exceeds +150°C.
Features
• Wide Input Supply Voltage Range
- Variable 5.6V to 24V
- Fixed 4.5V to 5.6V
• Three Independently Programmable Output Voltages
• Switching Frequency . . . . . . . . . . . . . . . . . . . . . . . 300kHz
• Out of Phase PWM Controller Operation
- Reduces Required Input Capacitance and Power
Supply Induced Loads
• No External Current Sense Resistor
- Uses Lower MOSFET’s r
DS(ON)
• Bidirectional Frequency Synchronization for
Synchronizing Multiple ISL6443s
• Programmable Soft-Start
• Extensive circuit protection functions
- PGOOD
- UVLO
- Overcurrent
- Over-temperature
- Independent Shutdown for Both PWMs
• Excellent Dynamic Response
- Voltage Feed-Forward with Current Mode Control
• QFN Packages:
- QFN - Compliant to JEDEC PUB95 MO-220
QFN - Quad Flat No Leads - Package Outline
- Near Chip Scale Package footprint, which improves
PCB efficiency and has a thinner profile
• Pb-Free Plus Anneal Available (RoHS Compliant)
Ordering Information
PART
NUMBER
ISL6443IR
PART
TEMP.
MARKING RANGE (°C)
ISL6443IR
-40 to 85
-40 to 85
PACKAGE
PKG.
DWG. #
28 Ld 5x5 QFN L28.5x5
28 Ld 5x5 QFN L28.5x5
(Pb-free)
ISL6443IRZ ISL6443IRZ
(See Note)
Add “-T” or “-TK” suffix for tape and reel.
NOTE: Intersil Pb-free plus anneal products employ special Pb-free
material sets; molding compounds/die attach materials and 100%
matte tin plate termination finish, which are 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.
Applications
• Power Supplies with Multiple Outputs
• xDSL Modems/Routers
• DSP, ASIC, and FPGA Power Supplies
• Set-Top Boxes
• Dual Output Supplies for DSP, Memory, Logic,
P
Core
and I/O
• Telecom Systems
FN9044 Rev 2.00
Aug 9, 2006
Page 1 of 18
ISL6443
Absolute Maximum Ratings
Supply Voltage (VCC_5V Pin) . . . . . . . . . . . . . . . . . . . . -0.3V to +7V
Input Voltage (V
IN
Pin). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .+27V
BOOT1, 2 and UGATE1, 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . +35V
PHASE1, 2 and ISEN1, 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . +27V
BOOT1, 2 with Respect to PHASE1, 2 . . . . . . . . . . . . . . . . . . +6.5V
UGATE1, 2. . . . . . . . . . . . (PHASE1, 2 - 0.3V) to (BOOT1, 2 +0.3V)
Thermal Information
Thermal Resistance (Typical)
JA
(°C/W)
JC
(°C/W)
28 Lead QFN (Note 1) . . . . . . . . . . .
36
5.5
Maximum Junction Temperature (Plastic Package) . -55°C to 150°C
Maximum Storage Temperature Range . . . . . . . . . . . -65°C to 150°C
Temperature Range . . . . . . . . . . . . . . . . . . . . . . . . . . . -40°C to 85°C
CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation of the
device at these or any other conditions above those indicated in the operational sections of this specification is not implied.
NOTE:
1.
JC
is measured in free air with the component mounted on a high effective thermal conductivity test board with “direct attach” features. For
JA
the “case temp” location is the center of the exposed metal pad on the underside of the package. See Tech Brief TB379.
Electrical Specifications
Recommended operating conditions unless otherwise noted. Refer to Block Diagram and Typical Application
Schematic. V
IN
= 5.6V to 24V, or VCC_5V = 5V ±10%, T
A
= -40°C to 85°C (Note 2),
Typical values are at T
A
= 25°C
TEST CONDITIONS
MIN
TYP
MAX
UNITS
PARAMETER
VIN SUPPLY
Input Voltage Range
VCC_5V SUPPLY
(Note 3)
Input Voltage
Output Voltage
Maximum Output Current
SUPPLY CURRENT
Shutdown Current (Note 4)
Operating Current (Note 5)
REFERENCE SECTION
Nominal Reference Voltage
Reference Voltage Tolerance
POWER-ON RESET
Rising VCC_5V Threshold
Falling VCC_5V Threshold
OSCILLATOR
Total Frequency Variation
Peak-to-Peak Sawtooth Amplitude (Note 6)
5.6
12
24
V
4.5
V
IN
> 5.6V, I
L
= 20mA
V
IN
= 12V
4.5
60
5.0
5.0
-
5.6
5.5
-
V
V
mA
SD1 = SD2 = GND
-
-
50
2.0
375
4.0
A
mA
-
-1.0
0.8
-
-
1.0
V
%
4.25
3.95
4.45
4.2
4.5
4.4
V
V
260
V
IN
= 12V
V
IN
= 5V
-
-
-
-
4.16
3.5
-
10
V
CC
- 0.6V
300
1.6
0.667
1.0
-
4.8
-
-
-
-
340
-
-
-
10.0
5.44
-
1.5
-
-
kHz
V
V
V
ns
MHz
V
V
ns
V
Ramp Offset (Note 7)
SYNC Input Rise/Fall Time (Note 7)
SYNC Frequency Range
SYNC Input HIGH Level
SYNC Input LOW Level
SYNC Input Minimum Pulse Width (Note 7)
SYNC Output HIGH Level
SHUTDOWN1/SHUTDOWN2
HIGH Level (Converter Enabled)
LOW Level (Converter Disabled)
Internal Pull-up (3A)
2.0
-
-
-
-
0.8
V
V
FN9044 Rev 2.00
Aug 9, 2006
Page 5 of 18
RF/Wirelessly
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