Atmel AT42QT1060手机触摸控制方案

Atmel公司的AT42QT1060是数字突发模式电荷转移容性传感器驱动器,特别设计用于手机控制应用.AT42QT1060能检测2到6个键,多达7个可配置的输入/输出线,还集成了用来驱动LED的PWM.AT42QT1060包括了所有的信号处理功能,适合各种变化条件应用.本文介绍了AT42QT1060的主要特性,应用电路以及在手机中应用框图.此外,还介绍了AT42EVK1060评估板的主要特性和电路图.

The AT42QT1060 (QT1060) is a digital burst mode charge-transfer (QT) capacitive sensor driver designed specifically for mobile phone applications. The device can sense from two to six keys; up to four keys can be disabled by not installing their respective sense capacitors (Cs). It also has up to seven configurable input/output lines, with Pulse Width Modulation (PWM) for LED driving.

This device includes all signal processing functions necessary to provide stable sensing under a wide variety of changing conditions, and the outputs are fully debounced. Only a few external parts are required for operation.

The QT1060 modulates its bursts in a spread-spectrum fashion in order to heavily suppress the effects of external noise, and to suppress RF emissions.

AT42QT1060 主要特性:

Configurations:

– Can be configured as a combination of keys and input/output lines

Number of Keys:

– 2 to 6

Number of I/O Lines:

– 7, configurable for input or output, with PWM control for LED driving

Technology:

– Patented spread-spectrum charge-transfer (direct mode)

Key Outline Sizes:

– 6 mm x 6 mm or larger (panel thickness dependent); widely different sizes and

shapes possible

Layers Required:

– One

Electrode Materials:

– Etched copper

– Silver

– Carbon

– Indium Tin Oxide (ITO)

Panel Materials:

– Plastic

– Glass

– Composites

– Painted surfaces (low particle density metallic paints possible)

Panel Thickness:

– Up to 10 mm glass (electrode size dependent)

– Up to 5 mm plastic (electrode size dependent)

Key Sensitivity:

– Individually settable via simple commands over serial interface

Interface:

– I2C-compatible slave mode (100 kHz). Discrete detection outputs

Power:

– 1.8V to 5.5V

Package:

– 28-pin 4 x 4 mm MLF RoHS compliant IC

Signal Processing:

– Self-calibration

– auto drift compensation

– noise filtering

– Adjacent Key Suppression

AT42QT1060 应用:

– Mobile appliances



图1.AT42QT1060应用电路



图2.AT42QT1060手机应用框图



图3.AT42EVK1060评估板外形图

This kit is for the evaluation and development of applications using the T42QT1060-MMU

(QT1060) 6 Channel QTouchTM Integrated Circuit (IC). In this example, the QT1060 is shown working in a battery powered Standalone mode, but can connected to a PC and/or User application by simple modifications/connections to the EVK1060A Evaluation Board.

The EVK1060A is configured with 6 capacitive keys (one as a Guard Channel), 6 General Purpose Inputs/Outputs (GPIOs) as Outputs (LED 0 - 5) and the seventh GPIO as an input channel (SW1).

Ensure the EVK1060A Evaluation Board has 6x clear feet fitted to underside of the PCB.

Insert the CR2032 3V battery provided into the battery holder on the EVK1060A.

The LEDs will illuminate in a set sequence, then extinguish.

Touch and hold the ON/OFF symbol - Power LED will illuminate indicating power to the

QT1060. Remove touch from the ON/OFF symbol.

Touch any of the 5 key(s) (Rewind (K0), Play (K1), Pause (K2), Forward (K3), Stop (K4)) on the EV1060A and the corresponding LED(s) will illuminate. (The number of LED(s)

If the Guard Channel (K5 which surrounds K0 - K4) is touched, then LED5 will illuminate.

Touch and hold the ON/OFF symbol - The Power LED will extinguish to indicating power to the QT1060 has been removed. Remove touch from the ON/OFF symbol.

The EVK1060A will power off after approximately 3 minutes of inactivity.



图4.AT42EVK1060评估板电路图