- 您现在的位置：买卖IC网 > PDF目录24662 > 933740730112 (NXP SEMICONDUCTORS) LIQUID CRYSTAL DISPLAY DRIVER, PDSO56 PDF资料下载
参数资料
| 型号： | 933740730112 |
| 厂商： | NXP SEMICONDUCTORS |
| 元件分类： | 显示驱动器 |
| 英文描述： | LIQUID CRYSTAL DISPLAY DRIVER, PDSO56 |
| 封装： | PLASTIC, VSOP-56 |
| 文件页数： | 6/44页 |
| 文件大小： | 192K |
| 代理商： | 933740730112 |
第1页第2页第3页第4页第5页当前第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页第34页第35页第36页第37页第38页第39页第40页第41页第42页第43页第44页
2001 Oct 02
14
Philips Semiconductors
Product specication
Universal LCD driver for low multiplex rates
PCF8576
6.5
Oscillator
6.5.1
INTERNAL CLOCK
The internal logic and the LCD drive signals of the
PCF8576 are timed either by the internal oscillator or from
an external clock. When the internal oscillator is used,
pin OSC should be connected to pin VSS. In this event, the
output from pin CLK provides the clock signal for
cascaded PCF8566s in the system.
Where resistor Rosc to VSS is present, the internal oscillator
is selected. The relationship between the oscillator
frequency on pin CLK (fclk) and Rosc is shown in Fig.9.
6.5.2
EXTERNAL CLOCK
The condition for external clock is made by connecting
pin OSC to pin VDD; pin CLK then becomes the external
clock input.
The clock frequency (fclk) determines the LCD frame
frequency and the maximum rate for data reception from
the I2C-bus. To allow I2C-bus transmissions at their
maximum data rate of 100 kHz, fclk should be chosen to be
above 125 kHz.
A clock signal must always be supplied to the device;
removing the clock may freeze the LCD in a DC state.
6.6
Timing
The timing of the PCF8576 organizes the internal data flow
of the device. This includes the transfer of display data
from the display RAM to the display segment outputs. In
cascaded applications, the synchronization signal SYNC
maintains the correct timing relationship between the
PCF8576s in the system. The timing also generates the
LCD frame frequency which it derives as an integer
multiple of the clock frequency (see Table 2). The frame
frequency is set by the MODE SET commands when
internal clock is used, or by the frequency applied to
pin CLK when external clock is used.
The ratio between the clock frequency and the LCD frame
frequency depends on the mode in which the device is
operating. In the power-saving mode the reduction ratio is
six times smaller; this allows the clock frequency to be
reduced by a factor of six. The reduced clock frequency
results in a significant reduction in power dissipation. The
lower clock frequency has the disadvantage of increasing
the response time when large amounts of display data are
transmitted on the I2C-bus.
When a device is unable to digest a display data byte
before the next one arrives, it holds the SCL line LOW until
the first display data byte is stored. This slows down the
transmission rate of the I2C-bus but no data loss occurs.
Table 2
LCD frame frequencies
6.7
Display latch
The display latch holds the display data while the
corresponding multiplex signals are generated. There is a
one-to-one relationship between the data in the display
latch, the LCD segment outputs and one column of the
display RAM.
6.8
Shift register
The shift register serves to transfer display information
from the display RAM to the display latch while previous
data is displayed.
Fig.9 Oscillator frequency as a function of Rosc.
f
clk
3.4
10
7
×
R
osc
------------------------
kHz
()
≈
10 4
MBE531
103
10
2
10
10 3
102
f
clk
(kHz)
R(k
)
osc
min
max
PCF8576 MODE
FRAME
FREQUENCY
NOMINAL
FRAME
FREQUENCY
(Hz)
Normal mode
64
Power-saving mode
64
f
clk
2880
-------------
f
clk
480
----------
相关PDF资料 |
PDF描述 |
|---|---|
| 933740730118 | LIQUID CRYSTAL DISPLAY DRIVER, PDSO56 |
| 933774680026 | LIQUID CRYSTAL DISPLAY DRIVER, U |
| 933841600005 | LIQUID CRYSTAL DISPLAY DRIVER, U |
| 935064190005 | LIQUID CRYSTAL DISPLAY DRIVER, U |
| 0560-6600-01 | HDSL & MDSL MAGNETICS For Conexant Bt8960 and Bt8970 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| 933748212 | 制造商:Lumberg Automation 功能描述:CONNECTOR, GDML 3011 LED 230 RG, DIN VALVE, CLEAR/BLACK, 3C + GROUND, LED, PG 11 制造商:Hirschmann Electronics GmbH & Co Kg 功能描述:GDML 250V black socket red/green LED |
| 93378-003 | 制造商:FCI 功能描述:MEMORY CARD RECEPTACLE - Bulk |
| 9337-A17R | 制造商:GC Electronics 功能描述: |
| 9337C | 制造商:Hubbell Premise Wiring 功能描述: |
| 9337-CHR-100 | 制造商:Belden Inc 功能描述: |
发布紧急采购，3分钟左右您将得到回复。