Patent ID: 6424128
Filing Date: 2002-07-23
Classification: G06F,H02M,Y02B

Abstract:
An electronic device, comprising:an internal circuit having a first operation mode consuming a first operational current and a second operation mode consuming a second operational current, which is smaller than said first operational current; a first regulator that provides a predefined supply voltage from an input voltage and having a current supply ability corresponding to said first operational current of said internal circuit; a second regulator having a current supply ability corresponding to said second operational current; and a power supply control unit to operate said first regulator in response to a first control signal instructing said first operation mode, and to operate said second regulator in response to a second control signal instructing said second operation mode, wherein said internal circuit and power supply control unit are provided in one semiconductor integrated circuit device; said first regulator is a switching regulator having a pulse output circuit formed in said semiconductor integrated circuit device and a smoothing circuit having an inductance and a condenser provided externally of said semiconductor integrated circuit device; said second regulator is a first series regulator formed in said semiconductor integrated circuit device; said internal circuit includes a signal processing unit and a memory unit; a first voltage line connected to said signal processing unit and a second voltage line connected to said memory unit are connected by a switch; a second series regulator is included to provide said predefined supply voltage from said input voltage; and said second operation mode of said internal circuit includes an operation for turning said switch ON in order to supply current from said first series regulator to said signal processing unit and said memory unit, and an operation in which said first series regulator is suspended from operation and said second series regulator is suspended from operation in order to supply current only to said memory unit when said switch is turned OFF.