Maximum output current: Current mainstream constant current source LED driver chip maximum output current is about 90mA per channel. The maximum output of a constant current at the same time is more significant for the display, because in a white balance, the constant current is required for each channel.
Constant current output channel number: constant current source output channel has 8-bit and 16-bit two specifications, now 16-bit mainstream, its main advantage is to reduce the size of the chip, to facilitate the LED driver board (PCB) wiring, especially for the small point spacing of the LED drive plate more favorable.
Accurate current output: one is the same chip channel between the current error value; the other is the output current error between different chips. Accurate current output is a key parameter, and the display uniformity of LED display has a great effect. The larger the error, the poorer the display uniformity, the more difficult the screen body to achieve the white balance. At present the mainstream constant current source chip (bit to bit) current error is generally within ± 3%, between the chip (chip to chip) current error within ± 6%.
Data shift Clock: it determines the transmission speed of the display data, which is the key index of the update rate of the display. As a large size display device, the display refresh rate should be above 85Hz, in order to ensure a stable picture (no scanning flicker). A high data shift clock is the basis for the screen to get a high refresh rate. At present, the mainstream constant current source driver chip shift clock frequency is generally above 15mhz~25mhz.