Solid-state lighting dimming

A solid-state lighting (SSL) driver for an SSL system, comprising:

• dimming control circuitry configured to control, depending on the value of an externally applied dim control signal with respect to a predetermined threshold, whether to perform dimming of light emitted by a light-emitting load using current-control-based dimming or pulse-width modulation (PWM) based dimming;
• current control circuitry that is, during times said dim control signal has a value greater than said predetermined threshold, configured to control and vary, depending on the value of the externally applied dim control signal, the magnitude of current flowing through a light-emitting load, and is, during times said dim control signal has a value that is less than said predetermined threshold, configured to maintain the current flowing through the light-emitting load at a constant magnitude;
• and
• PWM circuitry configured to control dimming of said light-emitting load during times said dim control signal has a value less than said predetermined threshold, said PWM circuitry configured to perform dimming of the light emitted by said light-emitting load by periodically disrupting the current flowing through said light-emitting load.

A method of controlling the brightness of light produced by a light-emitting load in a solid-state lighting (SSL) system, comprising:

• converting a scaled non-phase-cut AC voltage to a direct current (DC) voltage;
• applying said DC voltage to a DC supply input of an SSL driver;
• separate from converting said scaled non-phase-cut AC voltage to said DC voltage, forming a dim control signal based on said scaled non-phase-cut AC voltage;
• applying said dim control signal to a dim control input of said SSL driver;
• supplying DC power to a light-emitting load from a DC supply output of said SSL driver;
• and
• dimming the light produced by said light-emitting load based on the dim control signal applied to the dim control input of said SSL driver, said dimming the light comprising controlling a magnitude of current flowing through the light-emitting load for dimming levels within a first dimming range and periodically disrupting current flowing through said light-emitting load for dimming levels within a second dimming range.

A method of controlling dimming of light emitted by a light-emitting load, comprising:

• generating a DC supply voltage from said scaled non-phase-cut power signal;
• applying said DC supply voltage across a light-emitting load;
• generating a dim control signal based on said scaled non-phase cut power signal;
• and
• controlling dimming of light emitted by said light-emitting load using said dim control signal,
• wherein controlling dimming of the light emitted by said light-emitting load comprises controlling a magnitude of current flowing through the light-emitting load depending the value of said dim control signal to achieve dimming over a first range of dimming levels, and periodically disrupting current flowing through the light-emitting load while holding the magnitude of the current flowing through the light-emitting load constant to achieve dimming over a second range of dimming levels.