AS1163 datasheet(40/91 Pages) AMSOSRAM

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AS1163

Functional description

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DS001075 • v2-00 • 2025-Nov-21

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The corrected PWM values are clamped between 0 and 16'd65535 to prevent overflow or

negative value.

There could be a PWM frame with intermediately (or wrongly) corrected PWM values when

host modifies the related registers while the device is actively running. Because the reference

temperatures/correct factors/original PWM values may be set separately by host in different

time slot. It could happen that the compensation is done with the old reference temperature but

with the new correction factor or new PWM values. The compensation is only guaranteed to be

correct one PWM frame after all the registers are stable.

There could also be an intermediate (or wrong) RGB combination if the IC temperature

changes between the compensation of two drivers within the same channel. The RGB color is

only guaranteed to be correct one PWM frame after the IC temperature is stable.

Host MCU can read both the original PWM values or the corrected PWM values with the same

READPWMCHN command but with different payload.

Meanwhile the LEDs and the driver chip heat-up or cool-off due to a different self-heating. Until

the next temperature readout and PWM setting, color can potentially drift.

6.6.2

LED channel clustering

It is possible to connect the output drivers together to a single LED with a higher current.

When the drivers are clustered, the output of the drivers is synchronized in power, frequency

and shift. As a result, channel clustering preserves color quality. Technically, this means that

the SETPWMCHN and SETCURCHN to the main driver is also used for the aggregated

drivers.

With the CH_clustering bits in the OTP it is possible to select the configurations that are shown

in Figure 20.

When clustering is deployed, the PCB shall short-circuit the clustered drivers to merge the

currents. For example, when using clustering 2 (see Figure 20), R1 and R2, G1 and G2, and

B1 and B2, shall be connected together in the PCB respectively.

The outgoing arrows in Figure 20 denote the main driver, the incoming arrows the sub or

aggregated drivers; only SETPWMCHN to main drivers have effect, SETPWMCHN to sub

drivers are ignored. Similarly, SETCURCHN to main drivers have effect, SETCURCHN to sub

drivers are ignored."

AS1163 Datasheet(PDF) 40 Page - ams-OSRAM AG