A 150V input-capable synchronous buck converter has been released by Linear Technology that is claimed to deliver up to 100mA of continuous output current. The company’s LTC3639 operates from an input voltage range of 4.5V to 150V, which is said to eliminate the need for an external transient suspension device. The device utilises internal synchronous rectification and a programmable peak current-mode design to optimise efficiency over a broad range of output currents.
The company advises, the device delivers efficiencies as high as 92 percent and requires only 12µA of quiescent current, maximising battery run time and reducing thermal issues.
A user-programmable output current limit can set output current from 10mA to 100mA in effect this minimises the need to oversize external components and protecting high impedance sources. This device can be programmed with fixed output voltages of 1.8V, 3.3V or 5V or a resistor divider can be used to program outputs from 0.8V to VIN. The design of the device includes a thermally enhanced MSOP package that offers additional pin spacing required for high voltage inputs. This MSOP package with only three tiny externals results in a highly compact solution for a broad range of applications.
The device has internal high side and synchronous power switches, drawing 12µA at no load while maintaining output voltage regulation, this make it ideal for always-on battery-powered applications. The stability of the converter means no external compensation is required, simplifying the design .
Additional features include a 0.8V +1 percent feedback voltage reference, internal or external soft-start and a feedback comparator output which enables multiple LTC3639s to be connected in parallel for higher current applications.
Linear Technology
www.linear.com
