NXP Semiconductors OM6290, Руководство пользователя, Страница: 13 / 30

NXP Semiconductors
UM10300
User Manual OM6290
UM10300_1 © NXP B.V. 2008. All rights reserved.
User manual Rev. 1.0— 8 August 2008 13 of 30
voltages, resulting in a minimum of external components and low power consumption.
The PCF8531 is compatible with most microcontrollers and communicates via a two-line
bidirectional bus (I
2
C-bus). All inputs are CMOS compatible. Similar devices are
PCF8535 (65 rows x 133 columns) and PCF8811 (80 rows x 128 columns).
Remark: The icon mode is used to reduce current consumption. When only icons are
displayed, a much lower operating voltage (V
LCD
) can be used and the switching
frequency of the LCD outputs is reduced. In most applications it is possible to use V
DD
as
V
LCD
.
3.3.2 Features
ƒ Single-chip LCD controller/driver
ƒ 34 row and 128 column outputs
ƒ Display data RAM 34
⋅
128 bits
ƒ 128 icons (last row is used for icons)
ƒ Fast mode I
2
C-bus interface (400 kbit/s)
ƒ Software selectable multiplex rates: 1:17, 1:26 and 1:34
ƒ Icon mode with Mux rate 1:2:
•
Featuring reduced current consumption while displaying icons only
ƒ On-chip:
•
Generation of V
LCD
(external supply also possible)
•
Selectable linear temperature compensation
•
Oscillator requires no external components (external clock also possible)
•
Generation of intermediate LCD bias voltages
•
Power-on reset.
ƒ No external components required
ƒ Software selectable bias configuration
ƒ Logic supply voltage range V
DD1
to V
SS1
is 1.8 to 5.5 V
ƒ Supply voltage range for on-chip voltage generator V
DD2
and V
DD3
to V
SS1
to
V
SS2
is 2.5 to 4.5 V
ƒ
Display supply voltage range V
LCD
to V
SS
•
Normal mode 4 to 9 V
•
Icon mode 3 to 9 V
ƒ Low power consumption, suitable for battery operated systems
ƒ CMOS compatible inputs
ƒ
Manufactured in silicon gate CMOS process.