Datasheet

DS_INLC10AQ Revision 1.0_B

Inova Semiconductors Confidential

Page 24 of 35

4.2.4 Power Save Mode

When all LED channels are set to an intensity of 0, the device enters a power save mode for the current

sources driving the LEDs. I.e. the digLED_Set_RGB command must be issued with an RGB value of

0x000000 to enter the power save mode.

Recovering from this mode does not require any particular measures. I.e. the host just needs to issue a

digLED_Set_RGB command with the data field different from 0x000000 and the current sources are

restarted again. There is a delay of

approx. 1μs before the restart of the green PWM channel (no phase

shift applies to the green channel).

This is due to an internal ramp-up required by the analog circuitry. The same procedure is applied after

device power-up or a hardware reset, as the initial RGB value is 0x000000. I.e. the LEDs are all turned off

after power-up or a hardware reset.

4.3

Blue and Green Brightness Control Scaler

In operation, the color brightness of each LED is controlled via an 8-bit RGB parameter. This provides a

color space of 3 x 8 bit = 24 bit. The 8-bit RGB value is scaled to the 12-bit PWMmax value.

The PWMmax values can be read out with the digLED_Read_Param command.

The scaling equations of the green and blue channel are given in Table 22.

Color

Scaling

Blue

PWM = (PWMmax x RGB + 128) >> 8

Green

PWM = (PWMmax x RGB + 128) >> 8

Table 22

– Scaling of blue and green LED channel