An IC chip includes I/O bumps on a back side, a first die, a second die, a first circuit, and a second circuit. The first die has driver circuits for LED devices, the LED devices being located on a front-facing surface of the first die. The first circuit extends from the front side toward the back side and across a thickness of the first die. The first circuit provides electrical connections between the LED devices and at least some of the I/O bumps. The first die and the second die can be stacked vertically or arranged laterally adjacent. The second circuit extends between the first die and the second die to electrically connect the first die and the second die. A circuit board can be electrically connected to the IC chip through the I/O bumps to, among other things, provide power to the various components of the IC chip.