High voltage micro DC/DC converter XCL247/XCL248 series

Designed for space-saving and high-efficiency under light loads, these converters are ideal for a wide range of applications, including industrial and consumer use.

The XCL247/XCL248’s most notable feature is its high-voltage capability of 36V while achieving ultra space-saving (Figure 1).

Additionally, with a low quiescent current of just 11µA, the series delivers high efficiency across load conditions – 86% at VIN = 12V, VOUT = 5V, IOUT = 1mA, and 88% at IOUT = 300mA (Figure 2).

Leveraging its compact size and high efficiency, the XCL247/XCL248 can easily replace traditional, larger high-voltage LDO regulators, helping to resolve heat generation issues (Figure 3: size reduced by 40% from 8.0 x 12.5mm to 7.3 x 8.1mm as a thermal solution example).

The XCL247/XCL248 supports input voltages up to 36V, compatible with 12V and 24V power supplies widely used in industrial equipment. It provides an output current of 600mA (sufficient for communication modules, sensors, etc.) and operates across a -40°C to 105°C temperature range. Its coil-integrated design minimises PCB wiring patterns, drastically reducing noise radiation from current loops. Additionally, the integrated coil eliminates the need for external coil selection, streamlining component sourcing, evaluation, and registration during development.

Unlike most medium- and high-voltage DC/DC converters that use N-channel driver FETs, the XCL247/XCL248 series adopts P-channel driver FETs. This allows for 100% duty operation, enabling direct pass-through of the input voltage when it falls below the output voltage setting. This feature ensures stable operation even when the input-output voltage difference is small (Figure 4).

In addition, by utilising the Power Good function, which indicates when the output voltage has sufficiently ramped-up, along with the soft-start function during startup, it is possible to manage power sequencing for downstream loads, which is a common requirement in industrial equipment.

The XCL247 series uses a fixed PWM control method for stable operation with consistently low ripple voltage, while the XCL248 series employs automatic PWM/PFM switching control to maintain high efficiency across all load conditions. This allows users to choose the most suitable control method based on their specific application needs.

 The package adopts the compact and thermally efficient Cool Post Type DFN3030-10B (3.0 x 3.0 x 1.7mm). Despite being a high-voltage and compact product, its structure allows heat to dissipate through the PCB, enabling usage with reduced heat generation. (Figure 5).