The present invention relates to a direct AC drive circuit and a luminaire for driving at least one LED. The drive circuit comprises an LED string and an LED string switching unit. The LED string comprises a series connection of at least two LEDs, wherein the LED string is directly supplied with a rectified AC supply voltage. The LED string switching unit is configured to control at least one LED short-circuit unit, which is arranged in parallel with at least one LED of the LED string. The drive circuit comprises a device configured to provide a low supply voltage, which low supply voltage is also derived from said rectified AC supply voltage, wherein said low supply voltage is generated from an unused voltage of the LED string.