參數(shù)資料
型號(hào)： LM8207
廠(chǎng)商： National Semiconductor Corporation
英文描述： TFT 18 Gamma Buffer + VCOM Driver + Voltage Reference
中文描述： 液晶18伽瑪緩沖器的VCOM驅(qū)動(dòng)電壓基準(zhǔn)
文件頁(yè)數(shù)： 12/22頁(yè)
文件大小： 1393K
代理商： LM8207
Application Section
(Continued)
Figure 3
shows how the display information is refreshed.
Using the row and column drivers, one pixel is addressed at
the display. The column driver receives the digital color data
from the timing controller. The corresponding gamma volt-
age will be determined, using the gamma correction curve.
In fact, the gamma correction curve is just a voltage refer-
ence with 18 output tabs, which presets the color intensity
settings. This gamma voltage is written to the pixel. The
column driver selects one column at the time; the changing
in the load may affect the ‘tabs’ of the gamma correction
curve. This problem can be solved using ‘gamma buffers’ to
isolate the gamma correction curve from the column driver.
PRINCIPLE OPERATION of the LM8207
The LM8207 combines three basic functions used in TFT
displays:
Voltage Reference
To improve picture quality and to reduce brightness varia-
tions, a highly stable reference voltage is available. It has
a low drift over the operation temperature range. This
output voltage (OUT_V
) is used as the reference
voltage to define the gamma correction values.
Gamma Buffers
The gamma correction curve can be defined easily using
an external chain of precision resistors. To ensure load
independent gamma correction levels, 18 gamma buff-
ers, each having a low output resistance, can be used to
drive the TFT display column drivers.
V
COM
Buffer
The V
COM
buffer supplies a common voltage, which is
applied to the back plate of all the pixels. Writing color
information to all the pixels will cause high current varia-
tions at the V
COM
level so this V
COM
buffer is designed for
driving large output currents.
These three functions are discussed in detail in the following
sections.
VOLTAGE REFERENCE
The internal Voltage Reference of the LM8207 can be used
to improve picture stability. This accurate reference is highly
stable over the operation temperature range. The output
voltage (OUT_V
REF
) of the Voltage Reference can be set
using two external resistors. In the next two sections, the
possibilities for setting the output voltage of the Voltage
Reference and the operating range of the Voltage Reference
are discussed.
SETTING THE OUTPUT VOLTAGE OF THE VOLTAGE
REFERENCE
The output voltage of the Voltage Reference Amplifier
(OUT_V
) can be set using the internal reference in com-
bination with the internal amplifier and two external resistors.
In
Figure 4
a typical application circuit for V
REF
is given.
20137926
FIGURE 3. Block Diagram of a Typical TFT-LCD
L
www.national.com
12
相關(guān)PDF資料
PDF描述
LM8207MT TFT 18 Gamma Buffer + VCOM Driver + Voltage Reference
LM8207MTX TFT 18 Gamma Buffer + VCOM Driver + Voltage Reference
LM8261 RRIO, High Output Current & Unlimited Cap Load Op Amp in SOT23-5
LM8261M5 RRIO, High Output Current & Unlimited Cap Load Op Amp in SOT23-5
LM8261M5X RRIO, High Output Current & Unlimited Cap Load Op Amp in SOT23-5
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
LM8207MT 功能描述:LCD 驅(qū)動(dòng)器 RoHS:否 制造商:Maxim Integrated 數(shù)位數(shù)量:4.5 片段數(shù)量:30 最大時(shí)鐘頻率:19 KHz 工作電源電壓:3 V to 3.6 V 最大工作溫度:+ 85 C 最小工作溫度:- 20 C 封裝 / 箱體:PDIP-40 封裝:Tube
LM8207MT/NOPB 功能描述:LCD Gamma緩沖器 RoHS:否 制造商:Maxim Integrated 輸入補(bǔ)償電壓: 轉(zhuǎn)換速度: 電源電壓-最大:20 V 電源電壓-最小:9 V 電源電流: 最大功率耗散: 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:TQFN-38 封裝:Tube
LM8207MTX 功能描述:LCD 驅(qū)動(dòng)器 RoHS:否 制造商:Maxim Integrated 數(shù)位數(shù)量:4.5 片段數(shù)量:30 最大時(shí)鐘頻率:19 KHz 工作電源電壓:3 V to 3.6 V 最大工作溫度:+ 85 C 最小工作溫度:- 20 C 封裝 / 箱體:PDIP-40 封裝:Tube
LM8207MTX/NOPB 功能描述:LCD 驅(qū)動(dòng)器 RoHS:否 制造商:Maxim Integrated 數(shù)位數(shù)量:4.5 片段數(shù)量:30 最大時(shí)鐘頻率:19 KHz 工作電源電壓:3 V to 3.6 V 最大工作溫度:+ 85 C 最小工作溫度:- 20 C 封裝 / 箱體:PDIP-40 封裝:Tube
LM825 制造商:Pulse Electronics Corporation 功能描述:
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。

采購(gòu)需求

(若只采購(gòu)一條型號(hào)，填寫(xiě)一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

*型號(hào) *數(shù)量 廠(chǎng)商 批號(hào) 封裝
添加更多采購(gòu)

我的聯(lián)系方式

*
*
*