TMG39925 datasheet(21/96 Pages) OSRAM

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[v1-06] 2018-Feb-27

TMG3992 − Detailed Description

Gesture detection, proximity detection, and RGBC color

sense/ambient light sense functionality are controlled by a

state machine, as depicted in Figure 32, which reconfigures

on-chip analog resources when each functional engine is

entered. Functional states/engines can be individually included

or excluded from the progression of state machine flow. Each

functional engine contains controls (E.g. Gain, ADC integration

time, wait time, persistence, thresholds, etc.) that govern

operation. Control of the Led Drive pin, LDR, is shared between

Proximity, Gesture, and Pattern Burst functionality;

consequently, while Pattern Burst functionality is activated,

Gesture and Proximity should be deactivated.

Pattern Burst functionality uses a digital core that is

independent of the analog sensor operation. The logic internal

to the digital core is activated when PBEN=1, enabling Barcode

Patterns (IRBeam) to be burst. The scanner receives the IR burst

which emulates the pattern of reflected light during scan of a

traditional paper barcode. In this operational mode the LDR pin

is exclusively acquired. If proximity or gesture engines are also

enabled, data generated will be invalid. The color/ALS engine

does not use the IR LED, but cross talk from IR LED emissions

during an optical pattern transmission may affect results.

Most of the functional engines are controlled by dedicated

registers; however, controls for Gesture, and Pattern Burst are

all accessed by the same address space: 0xA0 to 0xAF. Because

each functional block serves a different purpose and utilizes

common on-chip resources, only one may be activated at a

time. For example, if Gesture and Pattern Burst engines are both

activated simultaneously, the data stored in address 0xAx is

available to both engines, but will only cause the intended

engine to function properly.

Figure 27:

Simplified State Diagram

Detailed Description

TMG39925 데이터시트(PDF) 21 Page - OSRAM GmbH