MAX8686ETL+

The MAX8686 current- mode, synchronous PWM stepdown regulator with integrated MOSFETs operates from a 4.5V to 20V input supply and generates an adjustable output voltage from 0.7V to 5.5V while delivering up to 25A per phase. The MAX8686 employs a peak current- mode architecture that operates with an adjustable switching frequency from 300kHz to 1MHz. An adjustable current- limit threshold allows for optimization for different applications with different load currents. Inductor current sense is achieved either using an external sense resistor or using a lossless inductor current- sense scheme. The foldback and hiccup current limit reduces the power dissipation during overload or short- circuit conditions and allows for autorecovery when the fault condition is removed. The MAX8686 offers the ability to start up monotonically even when there is a prebias output voltage. In addition, an adjustable soft- start capability allows for a controlled turn- on. The MAX8686 features an accurate 1% reference and offers a reference input that allows for a higher accuracy reference to be used for voltage tracking applications such as DDR memory. The MAX8686 can be paralleled (up to eight) together in a true multiphase mode to deliver up to 200A of output current. When operating in this mode, this device achieves better than 10% current balance between phases at full load. The MAX8686 supports programmable phase shedding to improve system efficiency during light load conditions. Other features include an enable input and a power- OK (POK) indicator used for power sequencing. The MAX8686 also features latch overvoltage protection that turns on the low- side MOSFET when the output voltage exceeds 120% of the nominal voltage. The MAX8686 is offered in a thermally enhanced 40- pin, 6mm x 6mm TQFN package.

Applications

• POL Power Supplies
• Module Replacements
• Telecom Equipment
• Networking Equipment
• Servers
• DDR Memory

Key features

• Operating Range from 4.5V to 20V Input Supply
• 1% Reference Voltage Accuracy Over Temperature
• Reference Input (REFIN) for Output Tracking or System Reference Voltage
• Adjustable Switching Frequency from 300kHz to 1MHz
• Single/Multiphase Operation Delivers Up to 25A/200A with Integrated MOSFETs
• Adjustable Current Limit
• Monotonic Output Voltage at Startup (Prebias)
• Output Sink and Source Current Capability
• Adjustable Soft- Start
• Thermal- Overload Protection
• Output Overvoltage Protection
• Thermally Enhanced 6mm x 6mm TQFN Package (4W)