DC/DC controller generates positive or negative regulated voltages

October 04, 2011 // By Paul Buckley
Linear Technology Corporation has introduced a wide input range DC/DC controller for boost, SEPIC and inverting power supply applications, capable of generating either positive or negative regulated output voltages.

The LT3759 has two voltage feedback error amplifiers and reference voltages. One set is for positive output voltages, the other is for negative output voltages, both off a single feedback pin, making the LT3759 a versatile DC/DC controller for many types of power supply designs.

The LT3759 operates over an input voltage range from 1.6 V to 42 V and is well suited for industrial, automotive, medical and telecom applications. With a programmable and synchronizable operating frequency from 100 kHz to 1MHz, designers can choose a wide range of inductors and capacitors to optimize size, performance and cost. The fixed frequency, current-mode control architecture results in stable operation over a wide range of supply and output voltages, and the use of all ceramic capacitors, enables a smaller solution size.

The LT3759 drives an external N-channel MOSFET from an internally regulated 4.75 V supply. Additional features include programmable soft-start, an accurate 50mV current sense threshold, programmable undervoltage lockout with hysteresis, and a power good signal along with output overvoltage and overcurrent protection.

Availability and Pricing

The LT3759 is available in a thermally enhanced MSOP-12 package with extended and industrial operating junction temperature ranges from -40 to 125°C while the H-grade version operates over a -40°C to 150°C junction temperature range.The 1000-piece price starts at $2.35 each.

More information about the LT3759 DC/DC controller at