Watches

A watch comprising:

• a timing circuit comprising input and output connections and configured to provide information about a current time;
• a smart watch circuit comprising input and output connections and configured to provide smart watch functionality;
• a first battery configured to provide energy to the timing circuit,
• wherein the first battery is configured to provide energy only to the timing circuit, wherein the timing circuit only provides watch functions selected from the group consisting of time keeping, alarms, timer and lapse;
• a second battery configured to provide energy to the smart watch circuit;
• and
• a communication circuit configured to provide communication between the timing circuit and the smart watch circuit;
• and
• wherein the communication circuit comprises a safety circuit configured to prevent leakage of current from the first battery to the second battery;
• wherein the safety circuit, configured to prevent leakage of current from the first battery to the second battery, comprises a first set of input and output connections of the safety circuit which are respectively connected to the input and output connections of the timing circuit, and comprises a second set of input and output connections of the safety circuit which are respectively connected to the input and output connections of the smart watch circuit;
• wherein the first set of input and output connections of the safety circuit are configured to float;
• wherein the second set of input and output connections of the safety circuit are configured to pull low for respective output connections and are further configured to use a pullup resistor for respective input connections;
• wherein the timing circuit is configured to provide a reset signal to the smart watch circuit.