The difference is not necessarily just “sensor vs. processor,” but the whole capture chain.

From the answers provided, the K-01 and K-5 appear to use very similar sensor technology, but not necessarily the exact same sensor. Their listed resolution and pixel pitch differ slightly, which suggests they are not identical parts.

The biggest cited difference is bit depth: the K-01 records 12-bit data, while the K-5 records 14-bit data. A 14-bit analog-to-digital conversion can represent more tonal steps than 12-bit, which can help preserve subtle tonal variation and can support greater measurable dynamic range if the sensor and noise performance also allow it.

That said, bit depth alone does not automatically guarantee more dynamic range. If the sensor’s usable highlight and shadow limits are the same, extra bits mostly reduce quantization artifacts rather than extending the actual range. But in practice, the A/D conversion and downstream processing can affect measured DR, especially in RAW measurements and in how data is mapped to JPEG.

So the short answer is: yes, differences in the sensor implementation, A/D bit depth, and processing pipeline can all contribute to the K-5 showing higher dynamic range than the K-01.