The quiescent current of the XTR11x (typically 200 μA) is the lower limit of the device output current. Zero input current (I_IN = 0 A) produces an I_O equal to the quiescent current. Output current does not begin to increase until I_IN > I_Q / 100. Current drawn from V_REF or V_REG adds to this minimum output current. This means that more than 3.7 mA is available to power external circuitry while still allowing the output current to go below 4 mA.