pcf85162 NXP Semiconductors, pcf85162 Datasheet - Page 30

• Manufacturer Part Number: pcf85162
• Description: Universal Lcd Driver For Low Multiplex Rates
• Manufacturer: NXP Semiconductors

NXP Semiconductors
PCF85162_1
Product data sheet
The SYNC line of all PCF85162 in the cascade must be connected to maintain the correct
synchronization between all cascaded PCF85162. Synchronization is guaranteed after a
Power-On Reset (POR). The only time that SYNC is likely to be needed is if
synchronization is accidentally lost (e.g. by noise in adverse electrical environments or by
defining a multiplex drive mode when PCF85162 with different SA0 levels are cascaded).
SYNC is organized as an input/output pin. The output selection is realized as an
open-drain driver with an internal pull-up resistor. A PCF85162 asserts the SYNC line at
the onset of its last active backplane signal and monitors the SYNC line at all other times.
If synchronization in the cascade is lost, it is restored by the first PCF85162 to assert
SYNC. The timing relationship between the backplane waveforms and the SYNC signal
for the various drive modes of the PCF85162 are shown in
Fig 20. Cascaded PCF85162 configuration
V
V
V
CONTROLLER
PROCESSOR/
SS
LCD
DD
(1) Is master (OSC connected to V
(2) Is slave (OSC connected to V
MICRO-
MICRO-
HOST
R
≤
2C
t r
B
Rev. 01 — 7 January 2010
DD
SYNC
SS
OSC
).
CLK
SDA
SCL
SYNC
).
OSC
SDA
SCL
CLK
A0
Universal LCD driver for low multiplex rates
A0
V
PCF85162
DD
A1
PCF85162
V
A1
(1)
DD
A2
(2)
A2 SA0 V
V
LCD
SA0
V
LCD
V
SS
32 segment drives
Figure
SS
4 backplanes
32 segment drives
BP0 to BP3
BP0 to BP3
(open-circuit)
21.
PCF85162
© NXP B.V. 2010. All rights reserved.
(up to 2048
LCD PANEL
elements)
013aaa067
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