ASAHI KASEI
[AK4181A]
AK4181A
Features:
Sampling Frequency: 125kHz(max)
Pen Pressure Measurement
On-Chip Thermo Sensor
Two Auxiliary Analog Inputs
Direct Battery Measurement
4-wire I/F
On-Chip Voltage Reference (2.5V)
12 bit SAR type A/D Converter with S/H circuit
Low Power Consumption (250µA)
Low Voltage Operation (2.7V - 3.6V)
Package
16pin TSSOP
Touch Screen Controller
General Description:
The AK4181A is a 4-wire touch screen controller that
incorporates a 12-bit 125kHz sampling SAR A/D converter.
The AK4181A can detect the pressed screen location by
performing two A/D conversions. In addition to location, the
AK4181A also measures touch screen pressure.
On-chip VREF can be utilized for two analog auxiliary
inputs and battery monitoring, with the ability to measure
voltages from 0V to 5V.
The AK4181A also has an on-chip temperature sensor.
DCLK
XP
CSN
YP
DIN
XN
Control
Logic
DOUT
BUSY
YN
IN1
Internal VREF(2.5V)
IN2
VBAT
R1
VREF+
AIN+
VREF-
VREF
R2
12bit
ADC
AIN-
(SAR type)
PENIRQN
PEN
INTERRUPT
Temp.
Sensor
VCC
GND
Block Diagram
MS0313-E-00
1
2004/06