Rohm Co., Ltd.

Keisuke Tsutsumi

Kiyotaka Umemoto

A semiconductor device, includes: a first semiconductor chip including a first semiconductor substrate; and a second semiconductor chip including a second semiconductor substrate, wherein the first semiconductor substrate has a first substrate main surface and a first substrate back surface facing opposite directions in a first direction, and includes a first region and a second region disposed on the first substrate main surface, wherein the first semiconductor chip includes: a first MOSFET of a first type structure formed to include the first region; and a control circuit formed to include the second region, wherein the second semiconductor chip includes a second MOSFET of a second type structure formed to include the second semiconductor substrate, and wherein the second type structure is different from the first type structure.

Semiconductor device

A power supply circuit has, for example, an overshoot suppressor, a control circuit, a first transistor M, a second transistor M, an inductor L, a capacitor C, resistors Rand R, and an error amplifier ERR. As the load becomes light, the ON-period of the second transistor Mincreases. When the load RL turns from a heavy load to a light or no load, the overshoot suppressordetects an increase in the ON-period of the second transistor M, and then forcibly turns OFF the second transistor M. Thus, an overshoot in the output voltage Vo is suppressed. Detecting an increase in the period for which the driving signal Sremains at high level H helps reduce malfunctioning due to noise.

Growing community of inventors

Kyoto, Japan

Keisuke Tsutsumi