WM8224 datasheet(27/50 Pages) WOLFSON

27 / 50 page

WM8224

Production Data

PD, Rev 4.1, June 2012

ADC resolution being used. As TARGETx[7:0] is an 8 bit register, the 4 MSBs of a data output code

cannot be changed.

16bit ADC Resolution

For 16bit resolution the target code entered into TARGETx[7:0] will ignore the 4 MSBs and 4 LSBs of

the 16-bit data output. For example if the desired code out is 0000111111110001, the value entered

into TARGETx[7:0] would be 11111111.

12bit ADC Resolution

For 12bit resolution the 4 MSBs of the 12 bit data output code will be ignored. For example if the

desired code out is 000011111111, the value entered into TARGETx[7:0] would be 11111111.

10bit ADC Resolution

For 10bit resolution the 4 MSBs of the 10bit data output code will be ignored. The 2 LSBs of the

target code should be set to ‘00’. For example if the desired code out is 0000111111, the value

entered into TARGETx[7:0] would be 11111100.

8bit ADC Resolution

For 8bit resolution the 4 MSBs of the 8bit data output code will be ignored. The 4 LSBs of the target

code should be set to ‘0000’. For example if the desired code out is 00001111, the value entered into

TARGETx[7:0] would be 11110000.

INDICATING THE START OF A BLC PROCEDURE

The start of a line is required to be indicated to the WM8224 to allow the black-pixel period to be

located. This can be achieved by two methods. The register TG_METHOD is set to reflect which

method is to be used.

METHOD 1: OEB PIN

The OEB pin can be shared with the BLC function to indicate the start of a line if the OEB functionality

is not required. To indicate the start of a line, send a line synchronisation pulse, TG, on the OEB pin.

It must be high for at least one rising edge of MCLK. The TG_METHOD register must be set to either

‘10’ or ‘11’ depending on whether positive or negative edge triggering is required, as shown in Figure

24.

Figure 24 Start of Line Indicator Using TG on the OEB Pin

WM8224 Datasheet(PDF) 27 Page - Wolfson Microelectronics plc