Chip with solder balls on the underside in a grid. Used for high-pin-count parts.
How it looks
Drawing: there is no BGA on CORE3588
A BGA chip. The RK3588 processor is one; it lives on the module that plugs into CORE3588, not on CORE3588 itself.
Real image: CORE3588, the module connector (the BGA is on the module)
CORE3588 top side: where the BGA lives instead, on a module plugged in above this area.
1J1, one of four connectors the computer module plugs into.
2J3, its partner on the other side. The module bridges the empty space between them, carrying the RK3588, a BGA chip with over a thousand balls. CORE3588 only routes signals from these connector pads.
How it works
Where it fits
A step beyond QFN. Processors (SoC) usually come as BGAs, which is why boards like CORE3588 buy them pre-mounted on a SoM and plug it in. A flat finish such as ENIG helps.