SFH5721 datasheet(40/54 Pages) OSRAM

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SFH 5721

DATASHEET

40 | Version 1.1 | 2022-02-28

Interrupts

The interrupt feature of Digital Light Sensor (DLS) IC simplifies and improves system efficiency by

eliminating the need to poll the sensor for data. The DLS IC implements four interrupt threshold

registers that allow the user to define thresholds above and below a desired light level. The user can

also select which data is used (from which readout channel; IEN register) for interrupt generation

and if interrupt is generated when all enabled channels produce an interrupt (And) or if a single

channel produces an interrupt (Or); IOA bit. To further control when an interrupt occurs, the DLS IC

provides an interrupt persistence feature. This feature allows the user to specify the number of

conversion cycles for which an event exceeding the interrupt threshold must persist, before

generating an interrupt.

Both IENL and IENH must be set to HIGH to activate interrupt functionality of a single channel. The

interrupt is activated when the selected measurement data is higher than the high threshold value

(determined by registers IHTH and IHTL) or lower than the low threshold value (determined by

registers ILTH and ILTL) for a consecutive number of measurements (determined by the IPERS[3:0]

bits). The counter keeping track of the number of consecutive detections is reset when the

measurement data is between the high threshold value and the low threshold value. Once the

interrupt is activated it can only be reset through the I2C interface by reading the IFLAG or DATA1L

(open-drain output).

SFH5721 Datasheet(PDF) 40 Page - OSRAM GmbH