pcf8536 NXP Semiconductors, pcf8536 Datasheet - Page 45

• Manufacturer Part Number: pcf8536
• Description: Universal Lcd Driver For Low Multiplex Rates Including A 6 Channel Pwm Generator
• Manufacturer: NXP Semiconductors

NXP Semiconductors
PCF8536
Product data sheet
Fig 30. PWM example waveforms for PWMI = 1
PWM register 5 = 127
PWM register 2 = 32
PWM register 3 = 64
PWM register 4 = 96
PWM register 0 = 0
PWM register 1 = 1
8.11.2 PWM inversion mode
The PWM inversion mode can be enabled by setting the PWMI bit to logic 1 (see
on page
By default, all PWM outputs will switch HIGH at the same time. If the PWM output is used
to drive external LEDs then this could cause a voltage dip on the power supply of the
LEDs. With the PWMI mode, it is possible to prevent multiple outputs switching HIGH at
the same time by ensuring that the PWM values are not identical.
In the example in
channels instead switch off together; however this will not cause any power supply
disturbances.
When PWM inversion mode is used, the PWM duty cycle can be calculated with:
DutyCycle
t =
128 x f
8). The PWMI mode will invert the PWM waveform.
1
=
PWM
128 PWMvalue
------------------------------------------- - 100
All information provided in this document is subject to legal disclaimers.
Figure
–
Universal LCD low multiplex driver with 6 channel PWM generator
128
Rev. 1 — 6 October 2011
30, none of the six PWM outputs switch HIGH together. All PWM
100.00 %
99.20 %
75.00 %
50.00 %
25.00 %

0.78 %
f
PWM
PCF8536
© NXP B.V. 2011. All rights reserved.
001aan570
Table 7
45 of 74
(10)