Portable power system using DC to DC converter

A handheld electrical device, comprising:

• a remote power source supplying power at a first voltage;
• a converter, a power conversion circuit of the converter having an input coupled to the remote power source by an electrical cord, the conversion circuit having an output, the conversion circuit selectively producing power at an output, the power produced at the output having a second voltage of a magnitude different from the first voltage, the output of the conversion circuit adaptable to be coupled to at least one functional electrical element of an electrical device by a power switch of the electrical device;
• an output impedance element of the conversion circuit connected to the output, a logic circuit of the converter coupled to the output impedance element by a voltage sense line, a control path coupling the logic circuit to the conversion circuit, the logic circuit sensing a drop in voltage across the output impedance element when the switch is turned on, the logic circuit transmitting a control signal on the control path to the conversion circuit responsive to sensing the drop in voltage, the conversion circuit producing power at the output responsive to receiving the control signal;
• and
• a trickle current path coupled between the input and the output of the power conversion circuit to permit a current to pass through the output impedance element, thereby creating a sense voltage across the output impedance element when the electrical device power switch is not turned on.

A power supply system for a handheld electrical device, comprising:

• a remote power source supplying power at a first voltage;
• a converter, a power conversion circuit of the converter having an input coupled to the remote power source by an electrical cord, the conversion circuit having an output, the conversion circuit selectively producing power at an output, the power produced at the output having a second voltage of a magnitude different from the first voltage, the output of the conversion circuit adaptable to be coupled to at least one functional electrical element of an electrical device by a power switch of the electrical device;
• at least one output impedance element of the conversion circuit connected to the output, a logic circuit of the converter coupled to the output impedance element by a voltage sense line, a control path coupling the logic circuit to the conversion circuit, the logic circuit sensing a drop in voltage across the output impedance element when the switch is turned on, the logic circuit transmitting a control signal on the control path to the conversion circuit responsive to sensing the drop in voltage, the conversion circuit producing power at the output responsive to receiving the control signal;
• and
• a trickle current path coupled between the input and the output of the power conversion circuit to permit a current to pass through the output impedance element, thereby creating a sense voltage across the output impedance element when the electrical device power switch is not turned on .