参数资料
型号: MAX1234EGI
厂商: MAXIM INTEGRATED PRODUCTS INC
元件分类: 消费家电
英文描述: 【15kV ESD-Protected Touch-Screen Controllers Include DAC and Keypad Controller
中文描述: SPECIALTY CONSUMER CIRCUIT, QCC28
封装: 5 X 5 MM, 0.80 MM HEIGHT, QFN-28
文件页数: 42/44页
文件大小: 706K
代理商: MAX1234EGI
M
±15kV ESD-Protected Touch-Screen
Controllers Include DAC and Keypad Controller
42
______________________________________________________________________________________
two 8-bit data streams write the command word into the
MAX1233/MAX1234. The next two 8-bit data streams
can contain either the input or output data.
QSPI Interface
Using the high-speed QSPI interface (
Figure
29) with
CPOL = 0 and CPHA = 0, the MAX1233/MAX1234 sup-
port a maximum f
SCLK
of 10MHz. DOUT data transi-
tions on the serial clock
s falling edge and is clocked
into the μP on the DCLK
s rising edge.
Layout, Grounding, and Bypassing
For best performance, use printed circuit boards with
good layouts; do not use wire-wrap boards even for
prototyping. Ensure that digital and analog signal lines
are separated from each other. Do not run analog and
digital (especially clock) lines parallel to one another, or
digital lines underneath the ADC package.
Figure
30 shows the recommended system ground
connections. Establish a single-point analog ground
(star ground point) at GND. Connect all analog grounds
to the star ground. Connect the digital system ground
to the star ground at this point only. For lowest noise oper-
ation, the ground return to the star ground
s power supply
should be low impedance and as short as possible.
High-frequency noise in the power supply may affect
the high-speed comparator in the ADC. Bypass the
supply to the star ground with a 0.1μF capacitor as
close to pins 1 and 2 of the MAX1233/MAX1234 as
possible. Minimize capacitor lead lengths for best sup-
ply-noise rejection. If the power supply is very noisy, a
10
resistor can be connected as a lowpass filter.
While using the MAX1233/MAX1234 with a resistive
touch screen, the interconnection between the convert-
er and the touch screen should be as short and robust
as possible. Since resistive touch screens have a low
resistance, longer or loose connections are a source of
error. Noise can also be a major source of error in
touch-screen applications (e.g., applications that
require a backlight LCD panel). This EMI noise can be
coupled through the LCD panel to the touch screen
and cause
flickering
of the converted data. Utilizing a
touch screen with a bottom-side metal layer connected
to ground couples the majority of noise to ground. In
addition, the filter capacitors from Y+, Y-, X+, and X-
inputs to ground also help reduce the noise further.
Caution should be observed for settling time of the
touch screen.
Definitions
Integral Nonlinearity
Integral nonlinearity (INL) is the deviation of the values
on an actual transfer function from a straight line. This
straight line can be either a best-straight-line fit or a line
drawn between the end points of the transfer function,
once offset and gain errors have been nullified. The
static linearity parameters for the MAX1233/MAX1234
are measured using the end-point method.
Differential Nonlinearity
Differential nonlinearity (DNL) is the difference between
an actual step width and the ideal value of 1LSB. A
DNL error specification of less than 1LSB guarantees
no missing codes and a monotonic transfer function.
Aperture Jitter
Aperture jitter (t
AJ
) is the sample-to-sample variation in
the time between the samples.
Aperture Delay
Aperture delay (t
AD
) is the time defined between the
falling edge of the sampling clock and the instant when
an actual sample is taken.
MAX1233
MAX1234
CS
SCK
MISO
MOSI
CS
DCLK
DOUT
DIN
QSPI
SS
V
DD
BUSY
PENIRQ
KEYIRQ
Figure 29. QSPI Interface
+3V/+5V
+3V/+5V
GND
SUPPLIES
DGND
V
DD
DV
DD
GND
AV
DD
DIGITAL
CIRCUITRY
*OPTIONAL
MAX1233
MAX1234
R* = 10
Figure 30. Power-Supply Grounding Connection
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相关代理商/技术参数
参数描述
MAX1234EGI+ 制造商:Maxim Integrated Products 功能描述:TOUCH SCREEN CONTROLLER 28-PIN QFN EP - Rail/Tube
MAX1234EGI-T 功能描述:触摸屏转换器和控制器 RoHS:否 制造商:Microchip Technology 类型:Resistive Touch Controllers 输入类型:3 Key 数据速率:140 SPS 分辨率:10 bit 接口类型:4-Wire, 5-Wire, 8-Wire, I2C, SPI 电源电压:2.5 V to 5.25 V 电源电流:17 mA 工作温度:- 40 C to + 85 C 封装 / 箱体:SSOP-20
MAX1234ETI+ 功能描述:触摸屏转换器和控制器 4Ch uWire QSPI/SPI Touch Interface RoHS:否 制造商:Microchip Technology 类型:Resistive Touch Controllers 输入类型:3 Key 数据速率:140 SPS 分辨率:10 bit 接口类型:4-Wire, 5-Wire, 8-Wire, I2C, SPI 电源电压:2.5 V to 5.25 V 电源电流:17 mA 工作温度:- 40 C to + 85 C 封装 / 箱体:SSOP-20
MAX1234ETI+T 功能描述:触摸屏转换器和控制器 4Ch uWire QSPI/SPI Touch Interface RoHS:否 制造商:Microchip Technology 类型:Resistive Touch Controllers 输入类型:3 Key 数据速率:140 SPS 分辨率:10 bit 接口类型:4-Wire, 5-Wire, 8-Wire, I2C, SPI 电源电压:2.5 V to 5.25 V 电源电流:17 mA 工作温度:- 40 C to + 85 C 封装 / 箱体:SSOP-20
MAX1234EVC16 功能描述:数据转换 IC 开发工具 MAX1233/34 Eval Kit RoHS:否 制造商:Texas Instruments 产品:Demonstration Kits 类型:ADC 工具用于评估:ADS130E08 接口类型:SPI 工作电源电压:- 6 V to + 6 V