전자부품 데이터시트 검색엔진
  Korean  ▼
ALLDATASHEET.CO.KR

X  

TSC2046EIPWRG4 데이터시트(PDF) 11 Page - Texas Instruments

Click here to check the latest version.
부품명 TSC2046EIPWRG4
상세설명  Low-Voltage I/O TOUCH SCREEN CONTROLLER
Download  32 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
제조업체  TI1 [Texas Instruments]
홈페이지  http://www.ti.com
Logo TI1 - Texas Instruments

TSC2046EIPWRG4 데이터시트(HTML) 11 Page - Texas Instruments

Back Button TSC2046EIPWRG4 Datasheet HTML 7Page - Texas Instruments TSC2046EIPWRG4 Datasheet HTML 8Page - Texas Instruments TSC2046EIPWRG4 Datasheet HTML 9Page - Texas Instruments TSC2046EIPWRG4 Datasheet HTML 10Page - Texas Instruments TSC2046EIPWRG4 Datasheet HTML 11Page - Texas Instruments TSC2046EIPWRG4 Datasheet HTML 12Page - Texas Instruments TSC2046EIPWRG4 Datasheet HTML 13Page - Texas Instruments TSC2046EIPWRG4 Datasheet HTML 14Page - Texas Instruments TSC2046EIPWRG4 Datasheet HTML 15Page - Texas Instruments Next Button
Zoom Inzoom in Zoom Outzoom out
 11 / 32 page
background image
TSC2046
SBAS265G − OCTOBER 2002 − REVISED JANUARY 2008
www.ti.com
11
INTERNAL REFERENCE
The TSC2046 has an internal 2.5V voltage reference that
can be turned on or off with the control bit, PD1 (see Table 5
and Figure 3). Typically, the internal reference voltage is only
used in the single-ended mode for battery monitoring,
temperature measurement, and for using the auxiliary input.
Optimal touch screen performance is achieved when using
the differential mode. The internal reference voltage of the
TSC2046 must be commanded to be off to maintain
compatibility with the ADS7843. Therefore, after power-up,
a write of PD1 = 0 is required to insure the reference is off
(see the Typical Characteristics for power-up time of the
reference from power-down).
Buffer
Band
Gap
Reference
Power−Down
To
CDAC
Optional
V
REF
Figure 3. Simplified Diagram of the Internal
Reference
REFERENCE INPUT
The voltage difference between +REF and –REF (see
Figure 2) sets the analog input range. The TSC2046
operates with a reference in the range of 1V to +VCC. There
are several critical items concerning the reference input
and its wide voltage range. As the reference voltage is
reduced, the analog voltage weight of each digital output
code is also reduced. This is often referred to as the LSB
(least significant bit) size and is equal to the reference
voltage divided by 4096 in 12-bit mode. Any offset or gain
error inherent in the ADC appears to increase, in terms of
LSB size, as the reference voltage is reduced. For
example, if the offset of a given converter is 2LSBs with a
2.5V reference, it is typically 5LSBs with a 1V reference.
In each case, the actual offset of the device is the same,
1.22mV. With a lower reference voltage, more care must
be taken to provide a clean layout including adequate
bypassing, a clean (low-noise, low-ripple) power supply, a
low-noise reference (if an external reference is used), and
a low-noise input signal.
The voltage into the VREF input directly drives the
capacitor digital-to-analog converter (CDAC) portion of the
TSC2046. Therefore, the input current is very low (typically
< 13
µA).
There is also a critical item regarding the reference when
making measurements while the switch drivers are ON. For
this discussion, it is useful to consider the basic operation of
the TSC2046 (see Figure 1). This particular application
shows the device being used to digitize a resistive touch
screen. A measurement of the current Y-Position of the
pointing device is made by connecting the X+ input to the
ADC, turning on the Y+ and Y– drivers, and digitizing the
voltage on X+ (Figure 4 shows a block diagram). For this
measurement, the resistance in the X+ lead does not affect
the conversion (it does affect the settling time, but the
resistance is usually small enough that this is not a concern).
However, since the resistance between Y+ and Y– is fairly
low, the on-resistance of the Y drivers does make a small
difference. Under the situation outlined so far, it is not
possible to achieve a 0V input or a full-scale input regardless
of where the pointing device is on the touch screen because
some voltage is lost across the internal switches. In addition,
the internal switch resistance is unlikely to track the
resistance of the touch screen, providing an additional
source of error.
Converter
+IN
+REF
Y+
+V
CC
V
REF
X+
Y
GND
−REF
−IN
Figure 4. Simplified Diagram of Single-Ended
Reference (SER/DFR high, Y switches enabled,
X+ is analog input)
This situation can be remedied as shown in Figure 5. By
setting the SER/DFR bit low, the +REF and –REF inputs
are connected directly to Y+ and Y–, respectively, which
makes the analog-to-digital conversion ratiometric. The
result of the conversion is always a percentage of the
external resistance, regardless of how it changes in
relation to the on-resistance of the internal switches. Note
that there is an important consideration regarding power
dissipation when using the ratiometric mode of operation
(see the Power Dissipation section for more details).


유사한 부품 번호 - TSC2046EIPWRG4

제조업체부품명데이터시트상세설명
logo
Burr-Brown (TI)
TSC2046EIPWR BURR-BROWN-TSC2046EIPWR Datasheet
554Kb / 23P
   Low Voltage I/O TOUCH SCREEN CONTROLLER
TSC2046EIPWR BURR-BROWN-TSC2046EIPWR Datasheet
645Kb / 30P
   Low Voltage I/O TOUCH SCREEN CONTROLLER
More results

유사한 설명 - TSC2046EIPWRG4

제조업체부품명데이터시트상세설명
logo
Texas Instruments
TSC2046E-Q1 TI1-TSC2046E-Q1 Datasheet
803Kb / 28P
[Old version datasheet]   LOW-VOLTAGE I/O TOUCH SCREEN CONTROLLER
logo
Burr-Brown (TI)
TSC2046 BURR-BROWN-TSC2046 Datasheet
554Kb / 23P
   Low Voltage I/O TOUCH SCREEN CONTROLLER
TSC2046E BURR-BROWN-TSC2046E_07 Datasheet
645Kb / 30P
   Low Voltage I/O TOUCH SCREEN CONTROLLER
logo
SHENZHEN FUMAN ELECTRON...
TSC2046S FUMAN-TSC2046S Datasheet
611Kb / 21P
   Low Voltage I/O Touch Screen Controller
logo
AiT Semiconductor Inc.
A8946 AITSEMI-A8946 Datasheet
753Kb / 24P
   TOUCH SCREEN DRIVER 4-WIRE RESISTANCE, LOW-VOLTAGE I/O INTERFACE
REV1.3
logo
Integrated Device Techn...
MK712 IDT-MK712 Datasheet
418Kb / 21P
   TOUCH SCREEN CONTROLLER
logo
Texas Instruments
ADS7843 TI1-ADS7843 Datasheet
652Kb / 18P
[Old version datasheet]   TOUCH SCREEN CONTROLLER
logo
Burr-Brown (TI)
ADS7843 BURR-BROWN-ADS7843 Datasheet
163Kb / 12P
   TOUCH SCREEN CONTROLLER
ADS7846 BURR-BROWN-ADS7846 Datasheet
520Kb / 23P
   TOUCH-SCREEN CONTROLLER
logo
Asahi Kasei Microsystem...
AK4182 AKM-AK4182 Datasheet
190Kb / 18P
   Touch Screen Controller
More results


Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32


데이터시트 다운로드

Go To PDF Page


링크 URL




개인정보취급방침
ALLDATASHEET.CO.KR
ALLDATASHEET 가 귀하에 도움이 되셨나요?  [ DONATE ] 

Alldatasheet는?   |   광고문의   |   운영자에게 연락하기   |   개인정보취급방침   |   링크교환   |   제조사별 검색
All Rights Reserved©Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn
Indian : Alldatasheet.in  |   Mexican : Alldatasheet.com.mx  |   British : Alldatasheet.co.uk  |   New Zealand : Alldatasheet.co.nz
Family Site : ic2ic.com  |   icmetro.com