The MAX191 operates from a single +5V supply or from dual 5V supplies, allowing ground-referenced bipolar input signals. The device features a logic power-down input, which reduces the 3mA VDD supply current to 50A max, including the internal-reference current. Decoupling capacitors are the only external components needed for the power supply and reference. This ADC operates with either an external reference, or an internal reference that features an adjustment input for trimming system gain errors.