April 7, 2006
Dual (180° Out-of-Phase) PWM and Linear
The ISL6442 is a high-performance, triple output controller
that provides a single high-frequency power solution
primarily for Broadband, DSL and Networking applications.
This device integrates complete control, monitoring and
protection functions for two synchronous buck PWM
controllers and one linear controller. Input voltage ripple and
total RMS input current is substantially reduced by
synchronized 180° out-of-phase operation of the two PWMs.
The two PWM buck converters provide simple voltage mode
control. The output voltage of the converters can be
precisely regulated to as low as 0.6V, with a maximum
tolerance of ±1.5% over temperature and line variations.
Programmable switching frequency up to 2.5MHz provides
fast transient response and small external components. The
linear controller provides a low-current output.
The ISL6442 has voltage-tracking capability. Each controller
has soft-start and independent enable functions combined
on a single pin. A capacitor from SS/EN to ground sets the
soft-start time; pulling SS/EN pin below 1V disables the
controller. Both outputs can soft-start into a pre-biased load.
The ISL6442 incorporates robust protection features. An
adjustable overcurrent protection circuit monitors the output
current by sensing the voltage drop across the upper
MOSFET rDS(ON). Hiccup mode overcurrent operation
protects the DC/DC converters from damage under over-
load and short circuit conditions. A PGOOD signal is issued
when soft-start is complete and PWM outputs are within 10%
of their regulated values and the linear regulator output is
higher than 75% of its nominal value. Thermal shut-down
circuitry turns the device off if the IC temperature exceeds
NUMBER* MARKING RANGE (°C) PACKAGE DWG. #
ISL6442IA ISL6442IA -40 to 85 24 Ld QSOP M24.15
ISL6442IAZ ISL6442IAZ -40 to 85 24 Ld QSOP M24.15
* Add “-TK” to 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.
• 4.5V to 5.5V or 5.5V to 24V Input Voltage Range
• ±1.5% PWM Switcher Reference Accuracy Over Line and
• Three Programmable Power Output Voltages
- Two PWM Controllers with Out-of-Phase Operation
- Voltage-Mode PWM Control
- One Linear Controller
• Programmable Switching Frequency from 300kHz to 2.5MHz
• Fast Transient Response
- High-Bandwidth Error Amplifier
• Extensive Circuit Protection Functions
- Overvoltage, Undervoltage, and Overtemperature
- Programmable Overcurrent Limit with Hiccup Mode
- Lossless Current Sensing (no Sense Resistor needed)
• Externally Adjustable Soft-Start Time
- Independent Enable Control
- Voltage Tracking Capability
- Able to Soft-Start into a Pre-Biased Load
• PGOOD Output with Delay
• 24 Ld QSOP
• Pb-Free Plus Anneal Available (RoHS Compliant)
• Complete 1 Chip Solution for DSL Modems/Routers
• DSP, ASIC, and FPGA Point of Load Regulation
• ADSL, Broadband and Networking Applications
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 1-888-468-3774 | Intersil (and design) is a registered trademark of Intersil Americas Inc.
Copyright Intersil Americas Inc. 2006. All Rights Reserved
All other trademarks mentioned are the property of their respective owners.