TMD2672

DIGITAL PROXIMITY DETECTOR

TAOS149C − AUGUST 2012

21

The LUMENOLOGY

r Company

r

r

Copyright

E 2012, TAOS Inc.

www.taosinc.com

Proximity Offset Register (0x1E)

The 8-bit proximity offset register provides compensation for proximity offsets caused by device variations,

optical crosstalk, and other environmental factors. Proximity offset is a sign-magnitude value where the sign

bit, bit 7, determines if the offset is negative (bit 7 = 0) or positive (bit 7 = 1). At power up, the register is set to

0x00. The magnitude of the offset compensation depends on the proximity gain (PGAIN), proximity LED drive

strength (PDRIVE), and the number of proximity pulses (PPULSE). Because a number of environmental factors

contribute to proximity offset, this register is best suited for use in an adaptive closed-loop control system. See

available TAOS application notes for proximity offset register application information.

Table 17.

6

75

4

2

31

0

POFFSET

Reset

0x00

MAGNITUDE

SIGN

FIELD

BIT

DESCRIPTION

SIGN

7

Proximity Offset Sign. The offset sign shifts the proximity data negative when equal to 0 and positive when

equal to 1.

MAGNITUDE

6:0

Proximity Offset Magnitude. The offset magnitude shifts the proximity data positive or negative, depending

on the proximity offset sign. The actual amount of the shift depends on the proximity gain (PGAIN), proximity

LED drive strength (PDRIVE), and the number of proximity pulses (PPULSE).