US Patent 7944410 Multi-line addressing methods and apparatus

This invention relates to methods and apparatus for driving electroluminescent, in particular organic light emitting diodes (OLED) displays using multi-line addressing (MLA) techniques. Embodiments of the invention are particularly suitable for use with so-called passive matrix OLED displays. A current generator for an electroluminescent display driver, the current generator including; a first, reference current input to receive a reference current; a second, ratioed current input to receive a ratioed current; a first ratio control input to receive a first control signal input; a controllable current mirror having a control input coupled to the first ratio control input, a current input coupled to the reference current input, and an output coupled to the ratioed current input; the current generator being configured such that a signal and the control input controls a ratio of the ratioed current to the reference current.