US 12,035,434 B1
Driver circuit and method for operating a light emitting unit
Thomas Jackum, Graz (AT); and Saska Lindfors, Graz (AT)
Assigned to Renesas Design (UK) Limited, Bourne End (GB)
Filed by Renesas Design (UK) Limited, Bourne End (GB)
Filed on Dec. 15, 2022, as Appl. No. 18/066,726.
Int. Cl. H05B 45/355 (2020.01); H05B 45/14 (2020.01)
CPC H05B 45/355 (2020.01) [H05B 45/14 (2020.01)] 15 Claims
OG exemplary drawing
 
1. A driver circuit for providing a driver current for operating a light emitting unit at a brightness level corresponding to a value of a brightness code; wherein the driver circuit comprises:
a digital-to-analog converter (DAC) stage configured to generate an intermediate signal in dependence of the value of the brightness code, wherein a level of the intermediate signal depends on a digital input value being inputted to the DAC stage, wherein the DAC stage is configured to convert the digital input value into an analog value representing a current using a linear mapping between the digital input value and the level of the intermediate level; and
a gain stage configured to amplify the intermediate signal in dependence of the value of the brightness code to provide the driver current for approximation of a target relationship between the brightness code and the driver current.