AK4186設計的電阻觸摸屏控制方案

本文介紹了AK4186主要特性，方框圖，4線和5線典型連接框圖，觸摸屏輸入電路以及AKD4186-A評估板電路圖。

AK4186是采用12位SAR ADC的 4線/5線電阻觸摸屏控制器，具有自動連續測量和測量數據計算功能以及連續讀出功能，I2C串行接口，取樣速率22.2kHz，工作電壓1.6V-3.6V，1.8V的功耗為60uA，并具有自動關機功能。主要用在手機，數碼相機，DVC和智能手機以及其它手提設備。

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)16pin QFN (3mm x 3mm, pitch 0.5mm)

圖1。AK4186方框圖

圖2。AK4186典型連接框圖（4線，AK4186ECB)

圖3。AK4186典型連接框圖（4線，AK4186EN)

圖4。AK4186典型連接框圖（5線，AK4186ECB)

圖5。AK4186典型連接框圖（5線，AK4186EN)

AKD4186-A評估板

AKD4186-A is the board for evaluation of the touch screen controller AK4186, which adopted the CSP small package suitable for the cellular phone, the handheld game machine. Since AKD4186-A has a touch-screen I/F and a digital I/O power supply input terminal, it is easily connectable with a target system of low power/voltage drive. Furthermore, since the analog input terminal is equipped analog voltage can also be measured.

圖6。觸摸屏輸入電路

圖7。AKD4186-A評估板電路圖