NXP Semiconductors
PCF8534A
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
Tfr
LCD segments
state 1
state 2
(a) Waveforms at driver.
(b) Resultant waveforms
at LCD segment.
mgl747
Fig 7.
Vstate1(t) = VSn(t) − VBP0(t).
Von(RMS) = 0.745VLCD.
Vstate2(t) = VSn(t) − VBP1(t).
Voff(RMS) = 0.333VLCD.
Waveforms for the 1:2 multiplex drive mode with 1⁄3 bias
PCF8534A_3
Product data sheet
Rev. 03 — 10 November 2008
© NXP B.V. 2008. All rights reserved.
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