AKM AK4186低功耗触摸屏控制方案

AKM 公司的AK4186是低功耗4线/5线电阻型触摸屏控制器,集成了带S/H电路的12位SAR ADC,具有4线或5线触摸屏接口,I2C串行接口,取样速率22.2kHz,工作电压1.6V-3.6V,并具有自动降功耗功能.本文介绍AK4186主要特性, 方框图, 4线/5线触摸屏轴测量框图, 笔压力测量框图, 4/5线触摸屏输入典型连接框图以及评估板AKD4186方框图, 触摸屏输入电路和评估板AKD4186 电路图.
AK4186: Low Power Touch Screen Controller with I2C Interface

The AK4186 is a 4-wire/ 5-wire resistive touch screen controller that incorporates 12bit SAR A/D converter. The AK4186 can detect the pressed screen location with two A/D conversions and it can also measure touch pressure. The AK4186 has both an automatic continuous measurement and a measurement data calculation function. The functions that normally require external processing, such as calculating the average screen input value, are processed by the AK4186. In addition, a new sequential mode achieves short coordinate measurement time while greatly reducing the microprocessor overhead. The AK4186 operates off of supply voltage down to 1.6V in order to connect a low voltage microprocessor. The AK4186 is the best fit for cellular phone, DSC, DVC, smart phone and other portable devices.
AK4186主要特性:
4-wire or 5-wire Touch Screen Interface
I2C Serial Interface
12bit SAR A/D Converter with S/H circuit
Sampling Rate: 22.2kHz
Pen Pressure Measurement (4-wire)
Continuous Read Function
Integrated Internal Osc (Sequence Mode)
Integrated Median Averaging Filter
Low Voltage Operation: VDD = 1.6V ~ 3.6V
PENIRQN Buffer Output
Low Power Consumption: 60μA at 1.8V
Auto Power Down
Package: 12pin CSP (1.7mm x 1.3mm, pitch 0.4mm)

图1.AK4186方框图

图2.4线触摸屏轴测量框图

图3.5线触摸屏轴测量框图

图4.笔压力测量框图

图5.4线触摸屏输入典型连接框图

图6.5线触摸屏输入典型连接框图
AK4186评估板Rev.1 AKD4186-A
AKD4186-A is the board for evaluation ...