TCS3771 Datasheet, PDF (14/33 Pages) ams AG – COLOR LIGHT-TO-DIGITAL CONVERTER with PROXIMITY SENSING

TCS3771
COLOR LIGHT-TO-DIGITAL CONVERTER
with PROXIMITY SENSING
TAOS110A − MARCH 2011
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 RGBC 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 RGBC Clear data (CDATA) falls outside of the desired
light level range, as determined by the values in the RGBC interrupt low threshold registers (AILTx) and RGBC
interrupt high threshold registers (AIHTx). Likewise, an out-of-range proximity interrupt can be generated when
lid ^{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 low threshold value must be less than the high
threshold value for proper operation.
a _{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 RGBC or proximity occurrences before an interrupt
v _{is generated. The persistence register (0x0C) allows the user to set the RGBC persistence (APERS) and the}
proximity persistence (PPERS) values. See the persistence register for details on the persistence filter values.
ill ^{Once the persistence filter generates an interrupt, it will continue until a special function interrupt clear command}
is received (see command register).
t _{PIHTH(r 0x0B), PIHTL(r 0x0A) PPERS(r 0x0C, b7:4)}
AG ^{t s} _Prox
Prox
s ^{n Integration ADC}
Prox
Data
Upper Limit
Lower Limit
Prox Persistence
am ^{nte Red}
Technical ^{co Clear}
PILTH(r 09), PILTL(r 08)
AIHTH(r 07), AIHTL(r 06)
APERS(r 0x0C, b3:0)
Clear
ADC
Clear
Data
Upper Limit
Lower Limit
RGBC Persistence
AILTH(r 05), AILTL(r 04)
Figure 13. Programmable Interrupt
The LUMENOLOGY r Company
r
r
www.taosinc.com
Copyright E 2011, TAOS Inc.
13