How do USB C devices know which way power is sent? The secret are these two little components near the connector, no microchips required.
For devices like USB power banks where they can both send and receive power on the same port, they're crucial for knowing what can charge it and what it can power. But many older, cheaply made USB C powered devices don't include them, meaning they don't power up at all.
Note that this is only for simple, 5 volt USB devices. Modern phones and laptops use USB PD (Power Delivery), which is a different spec.