The MAX4820/1 relay drivers will support a minimum of 70mA continuous current, as shown by the "OUT_ Drive Current" parameter in the Electrical Characteristics table (19-2751; Rev 2). Peak currents may exceed this limit, but you must ensure the RMS current does not exceed this specification. In practice, latching relays only require a current pulse to change relay position; therefore, the RMS current will depend on how often the current pulse is applied to the open-drain outputs. It is best to measure this RMS current during operation to determine if the 70mA continuous current specification will be violated.