STMPE821_09 STMICROELECTRONICS [STMicroelectronics], STMPE821_09 Datasheet - Page 41

• Manufacturer Part Number: STMPE821_09
• Description: 8-channel capacitive touch key controller
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

STMPE821
Basic PWM controller
Figure 9.
Ramps with programmable brightness, ON/OFF period and repetition
1 time
Duty
unit
cycle
Time
ON
Off
ON
Off
period
period
period
period
CS00055
“On” period = period 0[1:0] * time unit [3:0]
“Off” period = period 1[1:0] * time unit [3:0]
Duty cycle during “on” period = brightness [7:4]
Number of cycles = repetition [3:0]
Ramp up rate is programmable.
Figure 10. Fixed brightness output
time unit
Duty cycle
Time
CS00056
“On” period = period 0[1:0] * time unit [3:0]
Off period = don't care
Duty cycle during “on” period = brightness [7:4]
Number of cycles = repetition [3:0] = 0 (means infinite repetition)
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