Illumination apparatus and light emitting module

An illumination apparatus comprising:

• a plurality of light emitting modules connected in series;
• a constant current source configured to supply a current to the plurality of light emitting modules;
• a fault detection circuit configured to detect that the plurality of light emitting modules have at least one thereof with a short circuit fault,
• the plurality of light emitting modules each including:
• a light emitting device having an anode and a cathode;
• a threshold value detection circuit comprising:
• a first resistor having a first terminal and a second terminal;
• a Zener diode having an anode and a cathode;
• wherein the first terminal of the first resistor is connected to the cathode of the light emitting device and the second terminal of the first resistor is connected to the anode of the Zener diode;
• and
• wherein the cathode of the Zener diode is connected to the anode of the light emitting device;
• wherein the threshold value detection circuit comprises the Zener diode and the first resistor connected in series and is connected to the light emitting device in parallel;
• and
• a voltage/current conversion circuit comprising:
• a second resistor having a first terminal and a second terminal;
• and
• a transistor having an emitter, a collector, and a base;
• wherein the first terminal of the second resistor is connected to the cathode of the Zener diode and the anode of the light emitting device;
• wherein the second terminal of the second resistor is connected to the emitter of the transistor;
• wherein the collector of the transistor is connected to a current terminal for outputting a current externally from the light emitting module;
• wherein the base of the transistor is either directly connected to a connection terminal connecting the anode of the Zener diode and the second terminal of the first resistor, or connected to the connection terminal through a diode;
• and
• wherein the threshold value detection circuit is configured to output a constant voltage when the light emitting device has a normal state, whereas when the light emitting device has a short circuit fault, the threshold value detection circuit is configured to output a voltage equal to zero;
• wherein the voltage/current conversion circuit is configured to output a constant current when the voltage/current conversion circuit receives the constant voltage from the threshold value detection circuit, whereas when the voltage/current conversion circuit receives the voltage equal to zero, the voltage/current conversion circuit is configured to output a current equal to zero;
• wherein the fault detection unit is configured to detect whether the plurality of light emitting modules have a short circuit fault based on a total value of the constant current output from each the light emitting module;
• wherein the fault detection unit is configured to control the constant current source so as to stop current supply when the fault detection unit detects that the plurality of light emitting modules have a short circuit fault.