A lighting circuit for a light source, said light source being adapted to operate in a first operation mode and to operate in a second operation mode, comprising: a) a countercurrent prevention unit comprising a first control terminal and a second control terminal, wherein the first control terminal is adapted to be connected through a first operation mode switch to a power source (+B) and the second control terminal is adapted to be connected through a second operation mode switch to the power source (+B), the power source configured to provide a predetermined DC power voltage, the countercurrent prevention unit configured to transmit current from said control terminals (4, 5) to a switchable current controller; and b) said switchable current controller comprising: a common terminal and a switching terminal, the switchable current controller configured to be switchable, in response to the voltage (H, L) at said switching terminal, between the first operation mode supplying a first driving current and the second operation mode supplying a second driving current, whereby the first driving current and the second driving current are supplied from the common terminal to the light source, wherein the second driving current is smaller than the first driving current, wherein the countercurrent prevention unit further comprises: c) a first rectifier, wherein voltage at the first control terminal is provided to the switching terminal through the first rectifier; d) a first P-FET provided between the first control terminal and the common terminal; e) a second P-FET provided between the second control terminal and the common terminal; and f) a second rectifier provided between the second P-FET and the common terminal, wherein the second rectifier is series-connected to the second P-FET, and g) wherein when the first switch is closed and the DC power voltage is provided to the first control terminal, the voltage at said first control terminal switches said switchable current controller into said first operation mode, the first P-FET is turned-on and the second P-FET is turned-off, and the countercurrent prevention unit is configured to transmit current to the common terminal from said first control terminal through said turned-on first P-FET, and h) wherein when the second switch is closed and the DC power voltage is not provided to the first control terminal but provided to the second control terminal, the voltage at said second control terminal switches said switchable current controller into said second operation mode, the second P-FET is turned-on, and the countercurrent prevention unit is configured to transmit current to the common terminal from said second control terminal through said turned-on second P-FET. a) a countercurrent prevention unit comprising a first control terminal and a second control terminal, wherein the first control terminal is adapted to be connected through a first operation mode switch to a power source (+B) and the second control terminal is adapted to be connected through a second operation mode switch to the power source (+B), the power source configured to provide a predetermined DC power voltage, the countercurrent prevention unit configured to transmit current from said control terminals (4, 5) to a switchable current controller; and b) said switchable current controller comprising: a common terminal and a switching terminal, the switchable current controller configured to be switchable, in response to the voltage (H, L) at said switching terminal, between the first operation mode supplying a first driving current and the second operation mode supplying a second driving current, whereby the first driving current and the second driving current are supplied from the common terminal to the light source, wherein the second driving current is smaller than the first driving current, c) a first rectifier, wherein voltage at the first control terminal is provided to the switching terminal through the first rectifier; d) a first P-FET provided between the first control terminal and the common terminal; e) a second P-FET provided between the second control terminal and the common terminal; and f) a second rectifier provided between the second P-FET and the common terminal, wherein the second rectifier is series-connected to the second P-FET, and g) wherein when the first switch is closed and the DC power voltage is provided to the first control terminal, the voltage at said first control terminal switches said switchable current controller into said first operation mode, the first P-FET is turned-on and the second P-FET is turned-off, and the countercurrent prevention unit is configured to transmit current to the common terminal from said first control terminal through said turned-on first P-FET, and h) wherein when the second switch is closed and the DC power voltage is not provided to the first control terminal but provided to the second control terminal, the voltage at said second control terminal switches said switchable current controller into said second operation mode, the second P-FET is turned-on, and the countercurrent prevention unit is configured to transmit current to the common terminal from said second control terminal through said turned-on second P-FET.