原标题：Avago ADBM-A350小型光手指导航解决方案

　　Avago公司的ADBM-A350小型(SFF)光手指导航系统,具有低功耗和自动功率管理模式,使它非常适合以电池为能源和对功率敏感的应用如手机,高达20ips的高速运动检测,自调整祯速率以得到最佳性能,运动检测中断和手机检测中断,可选择125, 250, 500, 750, 1000 和1250 cpi分辨率,模拟和数字单电源1.8V工作,主要用在手指输入设备,移动设备,综合输入设备和以电池为能源的输入设备.本文介绍了ADBM-A350主要特性和典型应用电路.

　　The ADBM-A350 sensor is a small form factor (SFF) optical finger navigation system.

　　The ADBM-A350 is a low- power optical finger navigation sensor. It has a new, low-power architecture and automatic power management modes, making it ideal for battery-and power-sensitive applications such as mobile phones.

　　The ADBM-A350 is capable of high-speed motion detection – up to 20ips. In addition, it has an on-chip oscillator and integrated LED for optical navigation to minimize external components.

　　There are no moving parts, thus provide high reliability and less maintenance for the end user. In addition, precision optical alignment is not required, facilitating high volume assembly.

　　The sensor is programmed via registers through either a serial peripheral interface or a two wire interface port. It is packaged into a 17-pin FPC module for ease of assembly via ZIF connector.

　　Theory of Operation

　　The ADBM-A350 is based on Optical Finger Navigation (OFN) Technology, which measures changes in position by optically acquiring sequential surface images (frames) and mathematically determining the direction and magnitude of movement.

　　The ADBM-A350 contains an Image Acquisition System (IAS), a Digital Signal Processor (DSP), and a communication system.

　　The IAS acquires microscopic surface images via the lens and illumination system. These images are processed by the DSP to determine the direction and distance of motion. The DSP calculates the Δx and Δy relative displacement values.

　　The host reads the Δx and Δy information from the sensor serial port if a motion interrupt is published. The microcontroller then translates the data into cursor navigation, rocker switch, scrolling or other system dependent navigation data.

　　ADBM-A350主要特性:

　　Low power architecture

　　Self-adjusting power-saving modes for longer battery life

　　High speed motion detection up to 20ips

　　Self-adjusting frame rate for optimum performance

　　Motion detect interrupt

　　Finger detect interrupt

　　Soft click and Tap detect interrupt

　　Single Interrupt pin

　　Optional PWM output to control LED driver to enable illumination feature when fi nger is on the sensor

　　Optional switch input for center click function

　　Internal oscillator – no clock input needed

　　Selectable 125, 250, 500, 750, 1000 and 1250 cpi resolution

　　Single 1.8V supply voltage for analog and digital

　　Internal power up reset (POR)

　　Selectable Input/Output voltage at 1.8V or 2.8V nominal

　　4-wire Serial peripheral interface (SPI) or Two wire interface (TWI)

　　Integrated chip-on-board LED with wavelength of 870nm

　　17-pin FPC module

　　ADBM-A350应用:

　　Finger input devices

　　Mobile devices

　　Integrated input devices

　　Battery-powered input device

　　图1.ADBM-A350和1.8V MCU间通过SPI的接口电路