GENERAL DESCRIPTION

The SP6139 is a 1300kHz constant frequency, voltage mode, synchronous PWM step down controller optimized for high efficiency.

The SP6139 is adequately suited for split plane applications utilizing a low power 5V rail to power the controller circuitry, minimizing power dissipation. Its wide input voltage range of 3V to 15V allows for conversions from the standard 3.3V, 5V, 9.6V and 12V power rails to an output voltage adjustable down to 0.8V.

Developed around a wide bandwidth internal amplifier, the SP6139 can accommodate type II and type III compensation schemes.

Protection features include a programmable UVLO, thermal shutdown and output short circuit protection.

The SP6139 is part of a larger family of step down controllers operating at various switching frequencies up to 1300kHz and input voltages up to 28V. Refer to Exar’s SP6132, SP6132H, SP6134, SP6134H and SP6137 for complete details.

The SP6139 is available in lead free, RoHS compliant, space saving 10-pin MSOP package.

FEATURES

• 2.5V to 20V Step Down Achieved Using Dual Input

• On-Board 1.5Ω sink (2Ω source) NFET Drivers

• Up to 7A Output Capability

• UVLO Detects Both VCC and VIN

• Short-Circuit Protection with Auto Restart

• Supports Type II or III Compensation

• Programmable Soft Start

• Fast Transient Response

• High Efficiency: Greater than 94

• Non-synchronous Start-Up

• Small 10-Pin MSOP Package

• U.S. Patent #6,922,041

APPLICATIONS

• DSL Modems

• Set-Top Boxes

• 12V VIN Point of Load Applications