Abstract: A discharge prevention circuit and electronic equipment with the discharge prevention circuit are provided. The discharging prevention circuit includes a first power line, a second power line, a capacitor, a current detector and a switch. The first and second power lines directly or indirectly connect a power feed line to a load. The capacitor and the current detector are directly or indirectly connected in series between the first and second power lines. The switch is disposed in the first or second power line. The current detector detects at least charging current to the capacitor and discharging current from the capacitor. And if the current detector detects discharging current from the capacitor, the switch acts to stop current flow between the capacitor and the power feed line through the switch.

Abstract: A discharge prevention circuit and electronic equipment with the discharge prevention circuit are provided. The discharging prevention circuit includes a first power line, a second power line, a capacitor, a current detector and a switch. The first and second power lines directly or indirectly connect a power feed line to a load. The capacitor and the current detector are directly or indirectly connected in series between the first and second power lines. The switch is disposed in the first or second power line. The current detector detects at least charging current to the capacitor and discharging current from the capacitor. And if the current detector detects discharging current from the capacitor, the switch acts to stop current flow between the capacitor and the power feed line through the switch.

Abstract: In a switching type DC-DC converter, switching frequency f, gate to source voltage of a switching FET, and the stray capacity of the FET are decreased at light load period to increase conversion efficiency at light load. In another embodiment, no-load current is decreased by increasing self inductance of a smoothing choke at light load.

Abstract: A switching regulator comprises a single transformer having a primary winding connected in an input circuit for receiving direct-current energy and a secondary winding connected in an output circuit, and a switching transistor connected in series with the primary winding. A high frequency pulse generator triggers the switching transistor so that it interrupts the direct-current energy at a high frequency. A rectifier is provided for converting high frequency energy developed in the secondary winding into direct-current output energy, which is maintained constant by controlling the high frequency pulse generator. A low voltage detector produces a signal when the direct-current energy in the input circuit falls below a specified value. In response to the signal from the low voltage detector, constant direct-current energy is derived from a battery and applied to the output circuit as backup power.