pcf8534a NXP Semiconductors, pcf8534a Datasheet - Page 12

• Manufacturer Part Number: pcf8534a
• Description: Universal Lcd Driver For Low Multiplex Rates
• Manufacturer: NXP Semiconductors

NXP Semiconductors
PCF8534A_3
Product data sheet
7.4.4 1:4 Multiplex drive mode
When four backplanes are provided in the LCD, the 1:4 multiplex drive mode applies, as
shown in
Fig 9.
Sn+1
Sn+2
Sn+3
state 1
state 2
BP2
BP0
BP1
BP3
Sn
Figure
V
V
V
V
Waveforms for the 1:4 multiplex drive mode with
state1
on(RMS)
state2
off(RMS)
(t) = V
(t) = V
V
2V
V
V
V
2V
V
V
V
2V
V
V
V
2V
V
V
V
2V
V
V
V
2V
V
V
V
2V
V
V
V
2V
V
V
V
2V
V
V
2V
V
0 V
0 V
V
2V
V
V
2V
V
LCD
LCD
SS
LCD
LCD
SS
LCD
LCD
SS
LCD
LCD
SS
LCD
LCD
SS
LCD
LCD
SS
LCD
LCD
SS
LCD
LCD
SS
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
9.
= 0.577V
= 0.333V
LCD
LCD
/ 3
/ 3
/ 3
/ 3
/ 3
/ 3
/ 3
/ 3
/ 3
/ 3
/ 3
/ 3
/ 3
/ 3
/ 3
/ 3
/ 3
/ 3
/ 3
/ 3
/ 3
/ 3
Sn
Sn
/ 3
/ 3
Rev. 03 — 10 November 2008
(t)
(t)
LCD
LCD
V
V
BP0
BP1
.
.
(t).
(t).
(b) Resultant waveforms
(a) Waveforms at driver.
at LCD segment.
Universal LCD driver for low multiplex rates
T
fr
1
3
bias
PCF8534A
state 1
state 2
mgl749
© NXP B.V. 2008. All rights reserved.
LCD segments
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