MAXIM MAX8737ETE+

The MAX8737 dual high-power linear regulator controller uses external N-channel MOSFETs to generate two independent low-voltage rails for notebook computers. The MAX8737 provides low output voltages from 0.5V to 2.5V with ±5mV no-load accuracy. External components support scalable current designs with excellent load regulation (1%) at loads up to 5A. The regulator operates at low input voltages, which also reduces power dissipation in the external N-channel MOSFETs. The controller is powered by a standard 5V system supply for the external MOSFET gate drivers.

The MAX8737 features current and thermal limiting to protect the linear regulator from damage. The MAX8737 uses an external resistor divider to implement foldback current limiting, reducing overall power dissipation. An external resistor divider is connected in series with the current-sense input (CS) to provide foldback current limiting and effectively reduce short-circuit power dissipation.

For low-cost applications where the current-sense resistor is omitted, an output undervoltage timeout function is available. The output undervoltage (UVP) timing depends on the voltage level at the VOUT pin. If the output voltage exceeds the regulation range, UVP detects this condition and shuts down the LDO. The controller uses an adjustable reference input (REFIN) to set the nominal output voltage (VOUT), which reduces cost and makes stability independent of output voltage.

Each linear regulator features adjustable soft-start and generates a delayed power-good (PGOOD) signal to indicate whether the linear regulator is in regulation. The MAX8737 is a low-cost solution requiring minimal external components, housed in a 4mm x 4mm, 16-pin thin QFN package.

• Low-cost dual linear regulator
• Output voltage accuracy ±5mV
• Independent 0.5V to 2.5V reference input
• Foldback current limiting protection
• Output undervoltage lockout protection
• Thermal limiting (internal sensor)
• 1.0V to 5.5V input supply voltage (external FET drain)
• 5V bias supply voltage
• Independent power-good open-drain output
• Independent enable input
• Soft-shutdown output discharge
• Low supply current (0.5mA)
• Shutdown supply current (5μA max)

• Notebook and Desktop Computers
• Point-of-Load Regulators
• VMCH and VCCP CPU Power Supplies
• Low-Voltage Bias Power Supplies
• Servers