An obvious application of a positive-to-negative converter is generating a negative voltage output from a positive input. However, a not-so-obvious use is to produce a stable output voltage in an application that has a widely varying input. For example, a converter in a battery-powered device, which has an inherently variable input voltage, can produce a stable output voltage even if input voltage falls below the absolute value of the output voltage. However, an obvious drawback is reverse polarity, which can be easily overcome in this application. The supplied circuitry can use the negative output as the system ground and the negative battery terminal as the “positive” voltage source.