PCF8577C datasheet(7/28 Pages) PHILIPS

7 / 28 page

1998 Jul 30

Philips Semiconductors

Product speciﬁcation

LCD direct/duplex driver with

I2C-bus interface

PCF8577C

6.5

Direct drive mode

The PCF8577C is set to the direct drive mode by loading

the MODE control bit with logic 0. In this mode only four

bytes are required to store the data for the 32 segment

drivers. Setting the BANK bit to logic 0 selects even bytes

(BANK A), setting the BANK bit to logic 1 selects odd bytes

(BANK B).

In the direct drive mode the SBV is auto-incremented by

two after the loading of each segment byte register. This

means that auto-incremented loading of BANK A or

BANK B is possible. Either bank may be completely or

partially loaded irrespective of which bank is being

displayed. Direct drive output waveforms are shown in

Fig.4.

6.6

Duplex mode

The PCF8577C is set to the duplex mode by loading the

MODE bit with logic 1. In this mode a second backplane

signal (BP2) is needed and pin A2/BP2 is used for this;

therefore A2 and its equivalent SBV bit V5 are undefined.

The SBV auto-increments by one between loaded bytes.

All of the segment bytes are required to store data for the

32 segment drivers and the BANK bit is ignored.

Duplex mode output waveforms are shown in Fig.5.

Fig.5 Duplex mode display output waveforms.

Von(rms) = 0.791 (VDD − VSS); Voff(rms) = 0.354 (VDD − VSS).

on rms

()

off rms

()

-----------------------

2.236

MGA738

VDD

VSS

0.5 (V

)

0.5 (V

)

VDD

VSS

0.5 (V

)

VDD

VSS

0.5 (V

)

0.5 (V

)

0.5 (V

)

BP2

BP1

Segment x

(Sx)

BP1

BP2

LCD

OFF / OFF

ON / OFF

OFF / ON

ON / ON

PCF8577C Datasheet(PDF) 7 Page - NXP Semiconductors

PCF8577C Datasheet(HTML) 7 Page - NXP Semiconductors

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28

Datasheet Download

Link URL