For portable measurement equipment, sometimes the power is provided by one or two lithium battery cells. This means a 3.6V or 7.2V supply is available, but signal capture often require higher voltages, as high as ±25V signal range. The analog multiplexer is often the only device that requires a high voltage supply to accommodate the incoming high voltage signals. For applications that switch between multiple circuits with different voltages on a common connector, designers need to make sure that a multiplexer or multi-channel switch will be able to handle the wide range in voltage signal levels. For example, if a customer needs to switch between an RS-485 and RS-232 circuit like the MAX3160 multiprotocol transceiver, then the multiplexer needs to operate at the highest voltage range of the RS-232, which is -25V to +25V signal swing. Typically, the +V and –V need to be generated, which complicates the power supply requirements.