TCS37725FN datasheet(21/51 Pages) OSRAM

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ams Datasheet

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[v1-01] 2018-Mar-14

TCS3772 − Principles of Operation

Interrupts

The interrupt feature simplifies and improves system efficiency

by eliminating the need to poll the sensor for light intensity or

proximity values outside of a user-defined range. While the

interrupt function is always enabled and it's status is available

in the status register (0x13), the output of the interrupt state

can be enabled using the proximity interrupt enable (PIEN) or

Clear interrupt enable (AIEN) fields in the enable register (0x00).

Four 16-bit interrupt threshold registers allow the user to set

limits below and above a desired light level and proximity

range. An interrupt can be generated when the Clear data

(CDATA) is less than the Clear interrupt low threshold registers

(AILTx) or greater than the Clear interrupt high threshold

registers (AIHTx). Likewise, an out-of-range proximity interrupt

can be generated when the proximity data (PDATA) falls below

the proximity interrupt low threshold (PILTx) or exceeds the

proximity interrupt high threshold (PIHTx).

It is important to note that the thresholds are evaluated in

sequence, first the low threshold, then the high threshold. As a

result, if the low threshold is set above the high threshold, the

high threshold is ignored and only the low threshold is evaluated.

To further control when an interrupt occurs, the device

provides a persistence filter. The persistence filter allows the

user to specify the number of consecutive out-of-range Clear

or proximity occurrences before an interrupt is generated. The

persistence register (0x0C) allows the user to set the Clear

persistence (APERS) and the proximity persistence (PPERS)

values. See the persistence register for details on the

persistence filter values. Once the persistence filter generates

an interrupt, it will continue until a special function interrupt

clear command is received (see command register).

Figure 26:

Programmable Interrupt

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