Philips Semiconductors
Universal LCD driver for low multiplex
rates
Product specification
PCF8576C
6.4 LCD drive mode waveforms
6.4.1 STATIC DRIVE MODE
The static LCD drive mode is used when a single backplane is provided in the LCD. Backplane and segment drive
waveforms for this mode are shown in Fig.5.
T frame
V DD
LCD segments
BP0
V LCD
V DD
Sn
V LCD
state 1
(on)
state 2
(off)
Sn 1
VDD
V LCD
(a) waveforms at driver
V op
state 1
0
Vop
V op
state 2
0
Vop
(b) resultant waveforms
at LCD segment
MBE539
Vstate1(t) = VSn(t) – VBP0(t)
Von(rms) = Vop
Vstate2(t)
=
VSn
+
(t)
1
–
VBP0(t)
Voff(rms) = 0 V
1998 Jul 30
Fig.5 Static drive mode waveforms (Vop = VDD − VLCD).
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