LC75879PT_13 Datasheet, PDF (20/35 Pages) ON Semiconductor – LCD Display Driver

LC75879PT
(7) SC … Segment on/off control data
This control data bit controls the on/off state of the segments.
SC
Display state
0
On
1
Off
Note that when the segments are turned off by setting SC to 1, the segments are turned off by outputting segment off
waveforms from the segment output pins.
(8) BU … Normal mode/power-saving mode control data
This control data bit selects either normal mode or power-saving mode.
BU
Mode
0
Normal mode
Power saving mode
In this mode, the internal oscillator circuit stops oscillation (the S69/OSCI pin is configured for segment output) if the IC is
in the internal oscillator operating mode (OC=0) and the IC stops receiving external clock signals (the S69/OSCI pin is
1
configured for external clock input) if the IC is in the external clock operating mode (OC=1).
The common and segment output pins go to the VSS level. However, the S1/P1 to S8/P8 output pins can be used as
general-purpose output ports under the control of the data bits P0 to P3.
(The general-purpose output port P1 to P4 can not be used as clock output or PWM output).
(9) PF0 to PF3 … PWM output waveform frame frequency setting control data
These control data bits set the frame frequency of the PWM output waveforms. However, when the PWM output
function isn’t used, these control data bits become invalid. In addition, when the external clock operating frequency
is set the fCK2=38[kHz] typ (EXF="1") in external clock operating mode (OC= "1") or when the serial data transfer
is the simple mode transfer, these control data bits become invalid.
Control data
PWM output waveform frame frequency fp[Hz]
PF0
PF1
PF2
PF3
Internal oscillator operating mode
(The control data OC is 0,
fosc=300[kHz] typ)
External clock operating mode
(The control data OC is 1 and EXF is 0,
fCK1=300[kHz] typ)
0
0
0
0
1
0
0
0
0
1
0
0
1
1
0
0
0
0
1
0
1
0
1
0
0
1
1
0
1
1
1
0
0
0
0
1
fosc/1536
fosc/1408
fosc/1280
fosc/1152
fosc/1024
fosc/896
fosc/768
fosc/640
fosc/512
fCK1/1536
fCK1/1408
fCK1/1280
fCK1/1152
fCK1/1024
fCK1/896
fCK1/768
fCK1/640
fCK1/512
1
0
0
1
fosc/384
fCK1/384
0
1
0
1
fosc/256
fCK1/256
Note : When is setting (PF0,PF1,PF2,PF3)=(1,1,0,1) and (X,X,1,1), the frame frequency is same as frame
frequency at the time of the (PF0,PF1,PF2,PF3)=(1,0,1,0) setting (fosc/896, fCK1/896).
X: don’t care
No.A1687-20/35