pcf8536 NXP Semiconductors, pcf8536 Datasheet - Page 13

• 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
8.1.5.1 Oscillator
Table 11.
Table 12.
The internal logic and LCD drive signals of the PCF8536 are timed either by the built-in
oscillator or from an external clock.
Internal clock:
generated from it. The oscillator runs at nominal 230 kHz. The relationship between this
frequency and the LCD frame frequency is detailed in
between this frequency and the PWM frame frequency is detailed in
Control over the internal oscillator is made with the OSC bit (see
internal oscillator is also switched on or off under certain combinations of modes which
are described in
OSC
0
0
Usage
LCD and/or PWM with internal oscillator
LCD and PWM with external oscillator
LCD with external oscillator
1
1
Fig 7.
OSCCLK
pin
(1) Can only be used with the internal oscillator (OSC = 0).
(2) Can only be used with an external oscillator (OSC = 1).
(3) Nominal value for divide factor q is 24; source clock is 230 kHz (see
(4) PWM requires an external or internal 230 kHz clock.
COE
Oscillator selection
Valid combinations of bits OSC, EFR, and COE
Typical use of bits OSC, EFR, and COE
(1)
COE
0
1
not used
not used
All information provided in this document is subject to legal disclaimers.
When the internal oscillator is used, all LCD and PWM signals are
Table
Universal LCD low multiplex driver with 6 channel PWM generator
Internal oscillator
230 kHz
13.
Rev. 1 — 6 October 2011
EFR
not used
not used
0
1
OSCCLK pin
inactive;
may be left floating
output of internal oscillator
frequency (prescaler)
9.6 kHz input
230 kHz input
OSC
1
0
0
1
(4)
PWM frame frequency
LCD frame frequency
Programmable
Programmable
selection, q
selection, p
divider
divider
OSC
0
1
1
Section
8.1.9. The relationship
Clock source
internal oscillator used
internal oscillator used
OSCCLK pin
OSCCLK pin
9.6 kHz
Section
0
CDE
not used
not used
Section
0
1
EFR
Section
(3)
PCF8536
(2)
8.1.9).
© NXP B.V. 2011. All rights reserved.
PWM waveform
LCD waveform
8.1.5). The
generator
generator
013aaa448
8.1.10.
EFR
not used
1
0
13 of 74