Current and power regulation circuits for LED driver

In combination with an LED integrated circuit (IC) driver having a voltage reference input IREF to control an IC output current for an LED load demand, the LED IC driver having a pulse width modulation converter operating at a substantially constant frequency with peak current and slope compensation, the LED IC driver having an internal transconductance amplifier to control the IC output current, and the IC driver having a disable IC input control to disconnect the LED load from the LED IC driver, the IC supplied with a input voltage, a current regulation system for the IC output current comprising:

• an under-voltage circuit which generates a first input to a junction which first input reduces the voltage reference signal when the input voltage to the LED driver falls below a predetermined level;
• an over-temperature control circuit which generates a second input to the junction which second input reduces the voltage reference signal when a proximally sensed temperature of the LED driver exceeds a predetermined level;
• wherein the junction is electrically coupled to the IREF input of the IC;
• and
• a low voltage turn OFF circuit generating and applying a disablement signal to the disable IC input control based upon sensing a very low voltage at the junction.

A current regulation system providing fine dimming controls, used in combination with an LED integrated circuit (IC) driver having a voltage reference input to control an IC output current for an LED lamp load and a LED IC driver input control, the IC supplied with an input voltage, the current regulation and dimming control for the IC output current comprising:

• an under-voltage control circuit which generates a first input to a junction which first input reduces a voltage reference signal at the junction when the input voltage to the LED driver falls below a predetermined level thereby dimming the LED lamp load;
• an over-temperature control circuit which generates a second input to the junction which second input reduces the voltage reference signal at the junction when a proximally sensed temperature of the LED driver exceeds a predetermined level thereby dimming the LED lamp load;
• first and second voltage limiters respectively on the under-voltage circuit and the overtemperature circuit, which cause the voltage reference signal at the junction to be the lower of the first input and the second input, and wherein the junction is electrically connected to the voltage reference input of the IC driver;
• and
• a low voltage turn OFF circuit generating and applying an IC disablement signal to the LED IC driver input control based upon sensing a very low voltage at the junction.