Maxim 公司的MAX3806是高增益線性前置放大器,主要用于激光測距. MAX3806工作電壓5V,能把光電二極管交流耦合的電流轉(zhuǎn)換成單端電壓信號,線性范圍高達(dá)40uAP,過載電流高達(dá)2mAP,5.0V時的功耗為50mW,可選擇增益為60K或30K,可選擇衰減為14dB,主要用于汽車中的LIDAR傳感器,手提測距的激光傳感器,測試測量和工業(yè)控制的激光傳感器.本文介紹了MAX3806的主要特性,功能方框圖以及典型應(yīng)用電路.

The MAX3806 is a high-gain linear preamplifier for distance measurement applications using a laser beam. The device operates from a single +5.0V supply and converts current from an AC-coupled photodiode into a single-ended voltage signal. The input accepts single pulses or bursts of pulses with widths down to 30ns.
The amplifier remains linear with input amplitudes from 42nAP (SNR = 3) to 40μAP. It can also withstand overload signals as large as 2mAP. The output stage is designed to drive a high-impedance load to deliver the output-voltage swing at the lowest possible power dissipation.
The gain of the preamplifier stage is selected using the GAIN pin to be 60k??or 30k?. There is also an internal 14dB attenuator that is selected using the ATT pin. The output stage can be disabled (high impedance).
The device is available in a 3mm x 3mm, 12-pin TQFN package and operates over the -40°C to +105°C temperature range.

MAX3806主要特性:
♦ +5V Supply Voltage
♦ Linearity Range Up to 40μAP
♦ Overload Current Up to 2mAP
♦ 50mW Power Dissipation at +5.0V
♦ 1.5pA/√Hz Noise Density at 60k??Gain
♦ 14nARMS Input-Referred Noise at 60k??Gain
♦ Selectable Gains (60k?, 30k?)
♦ Selectable 14dB Attenuation

MAX3806應(yīng)用:
LIDAR Sensors for Automotive Applications (ACC, Stop&Go)
Laser Sensors for Portable Distance
Measurement
Laser Sensors for Industrial Applications

                圖1.MAX3806功能方框圖

                 
                  圖2.MAX3806典型應(yīng)用電路

                    
                      圖3.MAX3806典型應(yīng)用電路(續(xù))