CAP1126 Datasheet, PDF (55/73 Pages) Microchip Technology – 6 Channel Capacitive Touch Sensor with 2 LED Drivers

CAP1126
TABLE 6-54: LED PULSE / BREATHE PERIOD EXAMPLE (CONTINUED)
Setting (HEX)
Setting (Decimal)
Total Breathe / Pulse Period (MS)
7Eh
126
7Fh
127
4032
4064
6.33 LED Pulse 2 Period Register
TABLE 6-55: LED PULSE 2 PERIOD REGISTER
ADDR R/W
Register
B7
B6
B5
85h
R/W
LED Pulse 2
Period
-
P2_
PER6
P2_
PER5
B4
P2_
PER4
B3
P2_
PER3
B2
P2_
PER2
B1
P2_
PER1
B0
P2_
PER0
Default
14h
The LED Pulse 2 Period register determines the overall period of a pulse operation as determined by the LED_CTL
registers (see Table 6-52 - setting 10b). The LSB represents 32ms so that a setting of 18h (24d) would represent a
period of 768ms. The total range is from 32ms to 4.064 seconds (see Table 6-54) with a default of 640ms.
APPLICATION NOTE: Due to constraints on the LED Drive PWM operation, any Breathe Period less than 160ms
(05h) may not be achievable. The device will breathe at the minimum period possible as
determined by the period and min / max duty cycle settings.
The Pulse 2 Behavior is shown in Figure 6-3 for non-inverted polarity (LEDx_POL = 1) and in Figure 6-4 for inverted
polarity (LEDx_POL = 0).
FIGURE 6-3:
Pulse 2 Behavior with Non-Inverted Polarity
Normal – untouched
operation
Touch Detected
(100% - Pulse 2 Min Duty Cycle) *
Brightness
Release Detected
X additional pulses after release
Normal – untouched
operation
LED
Brightness
...
Pulse
Period
(P2_PER)
(100% - Pulse 2 Max Duty Cycle) * Brightness
 2015 Microchip Technology Inc.
DS00001623B-page 55