Buck-boost DC-DC converter models optimised for 24V input operation

24-03-2021 | TDK | Power

TDK Corporation has introduced 20A 300W rated models to the TDK Lambda brand i7C series of non-isolated DC-DC converters. The output voltage of the latest step-up and step-down converters is adjustable from 8V to 24V, and they are optimised to run from a wide range input voltage of 9V to 36V. The converters seamlessly transition from buck to boost mode operation with no disruption in performance.

The series 20A models can obtain further high-power outputs from 12V or 24VDC power supplies or batteries. Compared to similarly rated isolated DC-DC converters, the series provides a notably lower cost, smaller size and high-efficiency levels of up to 97%. These extremely compact products are excellent for industrial, medical, drones, automated guided vehicles, and portable battery-powered equipment.

Through light load conditions, the device's control circuitry decreases power consumption. At zero load, the input current draw is typically only 5mA, which can be decreased to around 0.25mA when the remote on-off puts the converter into standby. The low quiescent current enables battery-powered equipment to remain functional longer through periods of non-operation.

The open frame 20A device measures 36.8mm W x 34mm L x 14.7mm H. The thermal design of the series provides for minimal output de-rating, even with low airflow conditions. The product’s design lessens the requirement for large external components, providing savings on both cost and board space.


Standard features for the series include a trim pin for output voltage adjustment, plus remote sense, remote on-off (positive or negative logic), input under-voltage, over-current and over-temperature protection. The full-featured models are optionally equipped with a power good signal and output current monitoring. To reduce system noise, the switching frequency can be synchronised to another model or to an external clock.

All models offer safety certification to the IEC/UL/CSA/EN 62368-1 standards, with CE marking to the Low Voltage and RoHS Directives.

By Natasha Shek