A control apparatus and a panel assembly are provided. The panel assembly comprises a panel device and a control apparatus. The panel device includes a plurality of organic light emitting diodes and a power system. The control apparatus is configured to control the panel device and includes a drive circuit and an interface. The drive circuit is electrically connected to the panel and is configured to retrieve a parameter of the panel device. The interface is configured to transmit a signal comprising the parameter to the power system so that the power system drives the organic light emitting diodes of the panel under a voltage level determined by the parameter.