A dimmable light emitting diode, LED, drive circuit, comprising: a silicon-controlled rectifier dimmer (TRIAC); a direct current bus; a rectification circuit coupled to the silicon-controlled rectifier dimmer (TRIAC), an output terminal of the rectification circuit being connected to the direct current bus, wherein the rectification circuit is configured to generate a direct current bus voltage to an LED load through the direct current bus; a linear drive circuit configured to control a drive current flowing through the LED load; and a bus voltage adjustment circuit comprising: a bleeder circuit connected between the direct current bus and ground; characterized in that the bus voltage adjustment circuit further comprises a control circuit configured to acquire a conduction angle signal of the silicon-controlled rectifier dimmer and control the direct current bus voltage to be near a lighting voltage of the LED load by adjusting a bleeder current of the bleeder circuit when the conduction angle signal is greater than an angle threshold, wherein the conduction angle signal indicates a conduction angle of the silicon-controlled rectifier dimmer, the angle threshold is set to correspond to a conduction angle signal when the direct current bus voltage is equal to the lighting voltage of the LED load during the conduction of the silicon-controlled rectifier dimmer. a silicon-controlled rectifier dimmer (TRIAC); a direct current bus; a rectification circuit coupled to the silicon-controlled rectifier dimmer (TRIAC), an output terminal of the rectification circuit being connected to the direct current bus, wherein the rectification circuit is configured to generate a direct current bus voltage to an LED load through the direct current bus; a linear drive circuit configured to control a drive current flowing through the LED load; and a bus voltage adjustment circuit comprising: a bleeder circuit connected between the direct current bus and ground; characterized in that the bus voltage adjustment circuit further comprises a control circuit configured to acquire a conduction angle signal of the silicon-controlled rectifier dimmer and control the direct current bus voltage to be near a lighting voltage of the LED load by adjusting a bleeder current of the bleeder circuit when the conduction angle signal is greater than an angle threshold, wherein the conduction angle signal indicates a conduction angle of the silicon-controlled rectifier dimmer, the angle threshold is set to correspond to a conduction angle signal when the direct current bus voltage is equal to the lighting voltage of the LED load during the conduction of the silicon-controlled rectifier dimmer. a bleeder circuit connected between the direct current bus and ground; characterized in that the bus voltage adjustment circuit further comprises a control circuit configured to acquire a conduction angle signal of the silicon-controlled rectifier dimmer and control the direct current bus voltage to be near a lighting voltage of the LED load by adjusting a bleeder current of the bleeder circuit when the conduction angle signal is greater than an angle threshold, wherein the conduction angle signal indicates a conduction angle of the silicon-controlled rectifier dimmer, the angle threshold is set to correspond to a conduction angle signal when the direct current bus voltage is equal to the lighting voltage of the LED load during the conduction of the silicon-controlled rectifier dimmer.