Semtech SX865x系列4或5線電阻觸摸屏控制方案

關鍵詞： Semtech , SX865x系列 , 電阻觸摸屏

Semtech公司的SX865x系列(SX8654, SX8655和SX8656)是4/5線電阻觸摸屏控制器,低電壓2.3V-3.6V工作,低功耗,關斷電流僅0.4uA,器件集成了LDO穩(wěn)壓器,4/5線觸摸屏接口,精密的比率12位ADC,高達5000(X-Y)座標/秒.主要用在游戲機,手提音樂設備,手機,DSC,DVR,POS/POI終端和觸摸屏監(jiān)視器.本文介紹了SX865x系列主要特性和方框圖, 接近檢測接口框圖,以及模擬前端(AFE)框圖, 觸摸接口框圖和應用框圖,典型應用電路框圖推薦外接元件數(shù)值表.

The SX8654, SX8655 and SX8656 belong to a family of high performance haptics enabled 4/5-wire resistive touch screen controller with proximity detection, optimized for hand held applications such as mobile phones, portable music players, game machines, point-of-sales terminal and other consumer and industrial applications. They feature a wide input supply range from 2.3V to 3.6V. The controller computes touch screen X-Y coordinates and touch pressure with a precision, low power 12-bit analog-digital converter. On-chip data averaging processing algorithms can be activated to reduce host activity and suppress system noise. The processing core features low power modes which intelligently minimize current in operation as well as in automatic shut-down.

A capacitive proximity detection circuit has been integrated into the SX8654 and SX8656 to enable host controlled power management for battery applications. Proximity detection above 5 cm is possible using either the resistive touch screen as the sensor or with a single conductive plate, with communication to the host via the serial interface.

The SX8654 and SX8655 also integrate a haptics motor driver for Linear Resonant Actuator (LRA) and Eccentric Rotating Mass (ERM) micro motors with up to 250mA drive current. Haptics control can be performed using either an external PWM signal or the I2C serial interface, providing simple host interfacing and minimizing its I/O requirement.

Integrated very high ESD protection, of up to ±15kV on display inputs not only saves cost and board area, but also increases application reliability.

The three devices have an ambient operating temperature range of -40°C to +85°C, and are offered in both a 4mm x 4mm, 20-lead QFN package and 2.07mm x 2.07mm 19-lead CSP package for spaceconscious applications.

SX865x系列主要特性:

Low Voltage Operation

2.3V to 3.6V Supply

Integrated Low Drop Out (LDO) Regulator

Low Power Consumption

30uA@2.3V 8ksps (ESR)

0.4uA Shut-Down Current

4/5-Wire Touchscreen Interface

      Precision, Ratiometric 12-bit ADC

Up to 5000 (X-Y) coordinates/second (c/s)

      Programmable Digital Filtering/Averaging

Touch Pressure Measurement (4-Wire)

      Programmable Operating Mode (Manual,Pen Detect, Pen Trigger)

Capacitive Proximity Sensing (SX8654/56)

No Additional Components Required

Uses Resistive Touchscreen or a Simple Conductive Area as the Sensor

>5 cm Detection Distance

8uA @ 200ms Scan Period

Fully Programmable (Sensitivity, etc)

Haptics Driver for LRA and ERM (SX8654/55)

Haptics Waveform Generation Control (I2C or PWM Input)

Short Circuit Protection

Early Warning and Over-Temperature Monitoring and Protection

400kHz I2C Serial Interface

Several Host Operating Modes Available

Maskable Interrupt Output (NIRQ)

Real-time Events Monitoring (AUX1-3)

      Polling (I2C)

Hardware, Software, and Power-On Reset

-40°C to +85°C Operating Temperature Range

15kV HBM & IEC ESD Protection

Small Footprint Packages

      Pb & Halogen Free, RoHS/WEEE compliant

SX865x系列應用:

Game Machines, Portable Music Players

Mobile Phones

DSC, DVR, Phones

     POS/POI Terminals

Touch-Screen Monitors

2011-8-18 11:10:38 上傳