Rainbow Electronics MAX5043 User Manual
General description, Applications, Features
General Description
The MAX5042/MAX5043 isolated multimode PWM power
ICs feature integrated switching power MOSFETs con-
nected in a voltage-clamped, two-transistor, power-circuit
configuration. These devices operate from a wide 20V to
76V input voltage range. The MAX5042 includes a hot-
swap controller for use with an external power MOSFET to
limit inrush current for applications where the power sup-
ply is plugged into a live power backplane. The MAX5043
does not include a hot-swap controller.
The voltage-clamped power topology of the MAX5042/
MAX5043 enables full recovery of stored magnetizing
and leakage inductive energy for enhanced efficiency
and reliability. Operating at up to 500kHz switching fre-
quency, these devices provide up to 50W of output
power. The MAX5042/MAX5043 allow the implementa-
tion of both forward and flyback voltage or current-mode
converter topologies. A dedicated latched external shut-
down provides protection in addition to internal thermal
shutdown.
The MAX5042/MAX5043 achieve higher efficiency when
used with secondary-side synchronous rectification.
These devices generate a look-ahead signal for driving
secondary-side synchronous rectifiers.
The MAX5042/MAX5043 are rated for operation over the
-40°C to +125°C temperature range and are available in
a small surface-mount 56-pin thin QFN package.
Warning: The MAX5042/MAX5043 are designed to
work with high voltages. Exercise caution.
Applications
High-Efficiency Telecom/Datacom Power
Supplies
Router/Switch Cards with 48V Backplane Power
Systems
Servers with 48V Backplane Power Systems
xDSL Line Cards
xDSL Line-Driver Power Supplies
Distributed Power Systems with 48V Bus
42V Automotive Power Supplies
Power-Supply Modules
Features
♦ Reliable Single-Stage Clamped Two-Switch Power
ICs for High Efficiency
♦ No Reset Winding Required
♦ Up to 50W Output Power
♦ Integrated High-Voltage 75mΩ Power MOSFETs
♦ 20V to 76V Wide Input Voltage Range
♦ Feed-Forward Voltage or Current-Mode Control
♦ Programmable Brownout Undervoltage Lockout
♦ Integrated Current Signal Amplifier for High-
Efficiency, Current-Mode Control
♦ Internal Overtemperature Shutdown
♦ Indefinite Short-Circuit Protection
♦ Integrated Thermally Protected High-Voltage
Startup Linear Regulator
♦ Integrated Hot-Swap Controller (MAX5042)
♦ Integrated Look-Ahead Signal Output Drives
High-Speed Optocoupler for Secondary-Side
Synchronous Rectification
♦ >90% Efficiency with Synchronous Rectification
♦ Up to 500kHz Switching Frequency
♦ High-Power (2.5W), Small-Footprint 56-Pin
Thermally Enhanced QFN Package
MAX5042/MAX5043
Two-Switch Power ICs with Integrated
Power MOSFETs and Hot-Swap Controller
________________________________________________________________
Maxim Integrated Products
1
Ordering Information
19-3046; Rev 0; 1/04
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
Pin Configurations appear at end of data sheet.
PART
TEMP RANGE
PIN-PACKAGE
MAX5042
ATN
-40°C to +125°C
56 Thin QFN
MAX5043
ATN*
-40°C to +125°C
56 Thin QFN
Selector Guide
PART
DESCRIPTION
MAX5042
Two-Switch Power IC with Integrated Power
MOSFETs and Hot-Swap Controller for Isolated
Power Supplies
MAX5043
Two-Switch Power IC with Integrated Power
MOSFETs for Isolated Power Supplies
EVALUATION KIT
AVAILABLE
*Future product—contact factory for availability.