Systems and methods for power control for a therapeutic tool

A method for providing controlled power via a direct current power control system of an endoscopic vessel harvesting device so as to provide controlled power to a heating element of a therapeutic tool of the endoscopic vessel harvesting device, the method comprising:

• receiving, at an input connection of the direct current power control system, power from a power supply;
• supplying power from the input connection to a first power control circuit and a second power control circuit of the direct current power control system,
• supplying constant output power from the first power control circuit during a first time interval to heat the heating element to a target temperature;
• supplying pulsed output power from the second power control circuit during a second time interval following the first time interval to maintain a temperature of the heating element within a target temperature range;
• receiving, at an output connection of the direct current power control system, the constant output power from the first power control circuit or the pulsed output power from the second power control circuit;
• supplying the constant output power or the pulsed output power from the output connection to the therapeutic tool;
• and
• supplying no power to the heating element during a third time interval following the second time interval to allow heat to dissipate from the heating element.

A method for making a direct current power control system for an endoscopic vessel harvesting system to provide controlled power to a therapeutic tool comprising a heating element, the method comprising:

• connecting an input connection to a circuit board comprising a first power control circuit and a second power control circuit, the input connection configured to receive power from a power supply, the first power control circuit configured to supply constant output power to the heating element during a first time interval to heat the heating element to a target temperature, and the second power control circuit configured to supply pulsed output power to the heating element during a second time interval following the first time interval to maintain a temperature of the heating element within a target temperature range;
• and
• connecting the circuit board to an output connection, the output connection configured to receive the constant output power and the pulsed output power to supply controlled power to the heating element of the therapeutic tool, wherein supplying of controlled power to the heating element comprises, in sequence, supplying the constant output power during the first time interval and then the pulsed output power during the second time interval to the heating element followed by a third time interval during which no power is supplied to the heating element to allow heat to dissipate from the heating element.

An endoscopic vessel harvesting system, comprising:

• a power supply;
• a therapeutic tool comprising a heating element connected to a cutting element;
• and
• a direct current power control system, comprising:
• an input connection configured to receive power from the power supply;
• a circuit board connected to the input connection, the circuit board configured to supply constant output power to the heating element during a first time interval to heat the heating element to a target temperature and to supply pulsed output power to the heating element during a second time interval following the first time interval to maintain a temperature of the heating element within a target temperature range;
• and
• an output connection connected to the circuit board, the output connection configured to receive one of the constant output power or the pulsed output power at a time, and to supply controlled power to the heating element, wherein supplying of controlled power to the heating element comprises, in sequence, supplying the constant output power during the first time interval and then the pulsed output power during the second time interval to the heating element followed by a third time interval during which no power is supplied to the heating element in order to allow heat to dissipate from the heating element to avoid overheating the heating element.