Patent ID: 8154262
Filing Date: 2012-04-10
Classification: H02M,Y02B

Abstract:
1. An electronic control system, comprising: a power supply unit which receives an input voltage from an external power source through an input line and produces a supply voltage lower than the input voltage from the input voltage; and a control unit which is transferred from a standby mode to a normal operation mode in response to satisfaction of a wake-up condition, receives a first quantity of electric current set at the supply voltage from the power supply unit through a supply line in the normal operation mode to consume the first quantity of electric current, and receives a second quantity of electric current of the supply voltage from the power supply unit through the supply line in the standby mode to consume the second quantity of electric current, the second quantity being smaller than the first quantity, wherein the power supply unit comprises: a voltage drop type switching regulator, having a capacitor, which applies the input voltage of the input line to a connection line in response to the standby mode of the control unit while accumulating electric charge in the capacitor, starts performing a switching operation in response to the satisfaction of the wake-up condition in the control unit to produce a transfer voltage on the connection line from the input voltage of the input line and to adjust the transfer voltage to an intermediate voltage, and performs the switching operation in response to the normal operation mode of the control unit to produce the intermediate voltage on the connection line from the input voltage of the input line; and a series regulator which produces the supply voltage on the supply line from either the input voltage of the input line or the input voltage of the connection line applied by the switching regulator in case of the standby mode of the control unit, starts a voltage regulating operation for the transfer voltage of the connection line in response to the satisfaction of the wake-up condition while using the electric charge of the capacitor of the switching regulator, and produces the supply voltage on the supply line from the intermediate voltage of the connection line produced by the switching regulator in response to the normal operation mode of the control unit, and wherein the series regulator comprises: a first series regulator which prohibits, in response to the standby mode of the control unit, an electric current from being transmitted from the connection line to the supply line, starts the voltage regulating operation in response to the satisfaction of the wake-up condition, and produces the supply voltage applied to the supply line from the intermediate voltage of the connection line in response to the normal operation mode of the control unit to supply a third quantity of electric current of the supply voltage to the supply line, a sum of the second and third quantities being equal to the first quantity, the third quantity being larger than the second quantity; and a second series regulator which produces the supply voltage applied to the supply line from the input voltage of the input line to supply the second quantity of electric current of the supply voltage to the supply line.