參數(shù)資料
型號(hào)： TSC2008IRGVR
廠商： TEXAS INSTRUMENTS INC
元件分類： 消費(fèi)家電
英文描述： SPECIALTY CONSUMER CIRCUIT, PQCC16
封裝： 4 X 4 MM, GREEN, PLASTIC, VQFN-16
文件頁(yè)數(shù)： 9/40頁(yè)
文件大?。?/td> 1028K
代理商： TSC2008IRGVR
Touch Screen Settling
Touch Detect
www.ti.com.......................................................................................................................................................... SBAS406B – JUNE 2008 – REVISED MARCH 2009
In some applications, external capacitors may be required across the touch screen to filter noise picked up by the
touch screen (that is, noise generated by the LCD panel or backlight circuitry). These capacitors provide a
low-pass filter to reduce the noise, but they also cause a settling time requirement when the panel is touched.
The settling time typically shows up as a gain error. The problem is that the input and/or reference has not
settled to its final steady-state value before the A/D converter samples the input(s) and provides the digital
output. Additionally, the reference voltage may continue to change during the measurement cycle.
There are two ways to resolve this issue. Option 1 is to stop or slow down the TSC2008 SCLK for the required
touch screen settling time. This option allows the input and reference to have stable values for the Acquire period
(three clock cycles of the TSC2008; see Figure 30). This option works for both the single-ended and the
differential modes. Option 2 is to operate the TSC2008 in the differential mode only for the touch screen
measurements and command the TSC2008 to remain on (touch screen drivers ON) and not go into power-down
(PD0 = 1). Several conversions are made, depending on the settling time required and the TSC2008 data rate.
Once the required number of conversions have been made, the processor commands the TSC2008 to go into its
power-down state on the last measurement. This process is required for X-Position, Y-Position, and Z-Position
measurements.
The PENIRQ can be used as an interrupt to the host. RIRQ is an internal pull-up resistor with a programmable
value of either 50k
(default) or 90k (which allows the total resistance from X+ to Y– to be as high as 30k).
Write command '1010' (setup command) followed by data '1xx0' sets the pull-up resistor to 90k
. NOTE: The
first three bits must be '0's and the select bit is the last bit. To change the pull-up resistor back to 50k
, issue
write command '1010' followed by data '0xx0'.
An example for the Y-position measurement is detailed in Figure 27. The PENIRQ output is pulled high by an
internal pull-up resistor. While in power-down mode with PD0 = 0, the Y– driver is on and connected to GND,
and the PENIRQ output is connected to the X+ input. When the panel is touched, the X+ input is pulled to ground
through the touch screen, and PENIRQ output goes low because of the current path through the panel to GND,
initiating an interrupt to the processor. During the measurement cycle for X-, Y-, and Z-Position, the X+ input is
disconnected from the PENIRQ pull-down transistor to eliminate any pull-up resistor leakage current from flowing
through the touch screen, thus causing no errors.
If the last command byte written to the TSC2008 contains PD0 = 1, the pen-interrupt output function is disabled
and cannot detect when the panel is touched. In order to re-enable the pen-interrupt output function under these
circumstances, a command byte must be written to the TSC2008 with PD0 = 0.
If the last command byte contains PD0 = 0, then the pen-interrupt function is enabled at the end of a conversion.
The end of conversion (EOC) occurs on the rising edge of PENIRQ.
In both cases previously listed, it is recommended that whenever the host writes to the TSC2008, the master
processor masks the interrupt associated to PENIRQ. This masking prevents false triggering of interrupts when
the PENIRQ line is disabled in the cases previously listed.
Copyright 2008–2009, Texas Instruments Incorporated
17
Product Folder Link(s): TSC2008
相關(guān)PDF資料
PDF描述
TSC2008IRGVT SPECIALTY CONSUMER CIRCUIT, PQCC16
TSC2008IYZGR SPECIALTY CONSUMER CIRCUIT, BGA12
TSC2008IYZGT SPECIALTY CONSUMER CIRCUIT, BGA12
TSC2008TRGVRQ1 SPECIALTY CONSUMER CIRCUIT, PQCC16
TSC2046EIPWG4 SPECIALTY CONSUMER CIRCUIT, PDSO16
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
TSC2008IRGVT 功能描述:觸摸屏轉(zhuǎn)換器和控制器 Nano-Pwr Touch Screen Controller RoHS:否 制造商:Microchip Technology 類型:Resistive Touch Controllers 輸入類型:3 Key 數(shù)據(jù)速率:140 SPS 分辨率:10 bit 接口類型:4-Wire, 5-Wire, 8-Wire, I2C, SPI 電源電壓:2.5 V to 5.25 V 電源電流:17 mA 工作溫度:- 40 C to + 85 C 封裝 / 箱體:SSOP-20
TSC2008IYZGR 功能描述:觸摸屏轉(zhuǎn)換器和控制器 Nano-Pwr Touch Screen Controller RoHS:否 制造商:Microchip Technology 類型:Resistive Touch Controllers 輸入類型:3 Key 數(shù)據(jù)速率:140 SPS 分辨率:10 bit 接口類型:4-Wire, 5-Wire, 8-Wire, I2C, SPI 電源電壓:2.5 V to 5.25 V 電源電流:17 mA 工作溫度:- 40 C to + 85 C 封裝 / 箱體:SSOP-20
TSC2008IYZGT 功能描述:觸摸屏轉(zhuǎn)換器和控制器 Nano-Pwr Touch Screen Controller RoHS:否 制造商:Microchip Technology 類型:Resistive Touch Controllers 輸入類型:3 Key 數(shù)據(jù)速率:140 SPS 分辨率:10 bit 接口類型:4-Wire, 5-Wire, 8-Wire, I2C, SPI 電源電壓:2.5 V to 5.25 V 電源電流:17 mA 工作溫度:- 40 C to + 85 C 封裝 / 箱體:SSOP-20
TSC2008-Q1 制造商:TI 制造商全稱:Texas Instruments 功能描述:1.2V to 3.6V, 12-Bit, Nanopower, 4-Wire Micro TOUCH SCREEN CONTROLLER with SPIa?￠
TSC2008RGVR 制造商:TI 制造商全稱:Texas Instruments 功能描述:1.2V to 3.6V, 12-Bit, Nanopower, 4-Wire Micro TOUCH SCREEN CONTROLLER with SPI?
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 廠商 批號(hào) 封裝
添加更多采購(gòu)

我的聯(lián)系方式

*
*
*