- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄385090 > AK4180 (Asahi Kasei Microsystems Co.,Ltd) Touch Screen Controller PDF資料下載
參數(shù)資料
| 型號(hào)： | AK4180 |
| 廠商： | Asahi Kasei Microsystems Co.,Ltd |
| 英文描述： | Touch Screen Controller |
| 中文描述： | 觸摸屏控制器 |
| 文件頁(yè)數(shù)： | 7/17頁(yè) |
| 文件大?。?/td> | 140K |
| 代理商： | AK4180 |
第1頁(yè)第2頁(yè)第3頁(yè)第4頁(yè)第5頁(yè)第6頁(yè)當(dāng)前第7頁(yè)第8頁(yè)第9頁(yè)第10頁(yè)第11頁(yè)第12頁(yè)第13頁(yè)第14頁(yè)第15頁(yè)第16頁(yè)第17頁(yè)
[ASAHI KASEI]
[AK4180]
<MS0195-E-01>
2003/02
7
A/D Converter for Touch Screen
The AK4180 incorporates a12-bit successive approximation resistor A/D converter for position measurement, temperature, and
battery voltage. The architecture is based on capacitive redistribution algorithm, and an internal capacitor array functions as the
sample/hold circuit.
The A/D converter output is a straight binary format as shown below:
Input Voltage
(
VREF-1.5LSB)~
VREF
(
VREF-2.5LSB) ~ (
VREF-1.5LSB)
---------
0.5LSB ~ 1.5LSB
0 ~ 0.5LSB
VREF: (VREF+) – (VREF-)
Output Code
FFF
FFE
---------
001
000
Table 1 Output Code
The A/D converter’s full scale measurements depend on the input mode.
Analog Inputs
Analog input is selected via the A2, A1, A0 and SER/ DFR bits in the control register. If the analog inputs are the X or Y-axis,
use SER/ DFR = “0”, which means differential mode, the full scale (
VREF) is the differential voltage between the non-inverting
terminal and the inverting terminal of the measured axis (e.g. (XP) – (XN)). Analog non-inverting input to A/D converter is the
non-inverting terminal of the non-measured axis while the inverting input is the inverting terminal of the measured axis. If the
SER/ DFR bit is set to “1”, which means single-ended mode, the full scale of A/D converter (
VREF) is the internal reference
voltage, or external reference voltage. Note that SER/ DFR bit should be set to ”0” if IN2 is selected as analog input;
nevertheless, IN2 is actually measured by single-ended mode.
Tracking time is the period from the falling edge of 5
th
DCLK to the falling edge of 8
th
DCLK after the detection of START bit.
the required settling time to charge the internal capacitors depends on the source impedance. If the source impedance, Rin, is 600
ohm, the settling time needs at least 1.5
μ
s (3 tDCLK@2MHz). The maximum throughput of A/D converter is 125kHz.
If the source impedance of analog input is larger than 600 ohm, longer tracking time is required.
The Position Detection of Touch Screen
The selected touch screen position is detected by the voltage measurement of one axis when the voltage is supplied between the
two terminals of the other axis. At least two A/D conversions are needed to get the two-dimensional (X/Y axis) position.
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| AK4180VT | Touch Screen Controller |
| AK4182A | Touch Screen Controller |
| AK4182AVN | Touch Screen Controller |
| AK4182 | Touch Screen Controller |
| AK4182VN | Touch Screen Controller |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| AK4180VT | 制造商:AKM 制造商全稱:AKM 功能描述:Touch Screen Controller |
| AK418192D | 制造商:ACCUTEK 制造商全稱:ACCUTEK MICROCIRCUIT CORPORATION 功能描述:65,536 x 32 Bit CMOS/BiCMOS Static Random Access Memory |
| AK418192G | 制造商:ACCUTEK 制造商全稱:ACCUTEK MICROCIRCUIT CORPORATION 功能描述:32,768 x 32 Bit CMOS/BiCMOS Static Random Access Memory |
| AK418192S | 制造商:ACCUTEK 制造商全稱:ACCUTEK MICROCIRCUIT CORPORATION 功能描述:65,536 x 32 Bit CMOS/BiCMOS Static Random Access Memory |
| AK418192W | 制造商:ACCUTEK 制造商全稱:ACCUTEK MICROCIRCUIT CORPORATION 功能描述:65,536 x 32 Bit CMOS/BiCMOS Static Random Access Memory |
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。