NXP Semiconductors
PCF8534
Universal LCD driver for low multiplex rates
BP0
BP1
Sn
Sn+1
state 1
state 2
VLCD
2VLCD/3
VLCD/3
VSS
VLCD
2VLCD/3
VLCD/3
VSS
VLCD
2VLCD/3
VLCD/3
VSS
VLCD
2VLCD/3
VLCD/3
VSS
VLCD
2VLCD/3
VLCD/3
0V
−VLCD/3
−2VLCD/3
−VLCD
VLCD
2VLCD/3
VLCD/3
0V
−VLCD/3
−2VLCD/3
−VLCD
Tframe
LCD segments
state 1
state 2
(a) Waveforms at driver.
(b) Resultant waveforms
at LCD segment.
mgl747
Fig 6.
Vstate1(t) = Vsn(t) − VBP0(t).
VON(rms) = 0.745 VLCD.
Vstate2(t) = V(sn)(t) − VBP1(t).
VOFF(rms) = 0.333 VLCD.
Waveforms for the 1:2 multiplex drive mode with 1⁄3 bias.
PCF8534_0
Preliminary datasheet
Rev. 00.05 — 20 February 2007
© NXP B.V. 2007. All rights reserved.
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