《電子技術(shù)應(yīng)用》
您所在的位置:首頁 > 模擬設(shè)計 > 解決方案 > Maxim MAX97220差分輸入耳機放大器解決方案

Maxim MAX97220差分輸入耳機放大器解決方案

2011-07-17
作者:Maxim公司
</a>放大器" title="放大器">放大器" title="放大器">放大器,5V電源時能以3VRMS驅(qū)動1K歐姆線路負載, 3.3V電源時能以2VRMS驅(qū)動600歐姆線路負載,工作電壓2.5V-5.5V, DirectDrive輸出,不需要隔直流電容,THD+N優(yōu)于90dB,18位SNR性能達112dB,主要用于STB,藍光和DVD播放器,LCD電視和音頻設(shè)備.本文介紹了MAX97220主要特性, 功能方框圖, MAX97220A評估板主要特性,電路圖,材料清單和PCB元件布局圖.

The MAX97220A/B is a differential input DirectDrive® line driver/headphone amplifier. This device is capable of driving line level loads with 3VRMS into 1kI with a 5V supply and 2VRMS into 600I loads from a 3.3V supply. A headphone load is capable of being driven with 125mW into 32I with a 5V supply. The IC is offered with an inter­nally fixed 6dB gain or an externally set gain through external resistors. The external gain setting nodes can also be used to configure filters for set-top box applica­tions. The IC has exceptional THD+N over the full audio bandwidth.

Two versions of the IC are available with different turn-on times (tON). The A and C versions for headphone applications feature a tON of 5.5ms while the B and D versions, intended for set-top-box applications, feature a 130ms tON. An on-chip charge pump inverts the power-supply input, creating a negative rail. The output stage of the amplifier is powered between the positive input sup­ply and the output of the charge pump. The bipolar sup­plies bias the output about ground, eliminating the need for large, distortion-introducing output coupling capaci­tors. The IC powers on and off without clicks or pops.

The IC is available in a 3mm x 3mm x 0.8mm, 16-pin TQFN and is specified over the extended -40NC to +85NC temperature range.

MAX97220主要特性:

Output Power 125mW into 32I with a 5V Supply

3VRMS Output Drive into 1kI with a 5V Supply

2VRMS Output Drive into 600I with a 3.3V Supply

Fully Differential Inputs

Fixed or Externally Adjustable Gain with No Clicks or Pops

Wide 2.5V to 5.5V Operating Range

DirectDrive Outputs Eliminate DC-Blocking Capacitors

Flat THD+N, Better Than 90dB in the Audio Band

18-Bit SNR Performance, 112dB

Footprint Compatible with the MAX9722

Simple Multimedia Interfaces

MAX97220應(yīng)用:

Set-Top Boxes

Blu-rayK and DVD Players

LCD Televisions

Prosumer Audio Devices

圖1.MAX97220功能方框圖

圖2.MAX97220簡化方框圖

圖3.MAX97220A和MAX9722 PCB布局圖

圖4.MAX97220A/B增益設(shè)定圖

MAX97220A評估板

The MAX97220A evaluation kit (EV kit) is a fully assembled and tested circuit board that evaluates the MAX97220A differential input DirectDrive® line driver/headphone amplifier. The device is capable of driving 125mW into 32Ω, or 3VRMS into 600Ω load, with a 5V supply.

The EV kit provides an externally set gain, is powered from a 2.5V to 5.5V single power supply, and includes a shutdown input. The EV kit also evaluates the MAX97220B, MAX97220C, and MAX97220D devices. Request a free MAX97220B, MAX97220C, and/or MAX97220D IC sample from the factory when ordering the EV kit.

MAX97220A評估板主要特性:

2.5V to 5.5V Single-Supply Operation

3VRMS Output Drive Into 600ω Load

125mW Headphone Amplifier

Fully Differential Inputs

Externally Adjustable Gain

Low-Power Shutdown Input

Evaluates the MAX97220B, MAX97220C, and MAX97220D (with IC Replacement)

Fully Assembled and Tested

圖5.MAX97220A評估板電路圖
MAX97220A評估板材料清單(BOM):


圖6.MAX97220A評估板PCB元件布局圖
詳情請見:
http://datasheets.maxim-ic.com/en/ds/MAX97220A-MAX97220D.pdf

http://datasheets.maxim-ic.com/en/ds/MAX97220AEVKIT.pdf



本站內(nèi)容除特別聲明的原創(chuàng)文章之外,轉(zhuǎn)載內(nèi)容只為傳遞更多信息,并不代表本網(wǎng)站贊同其觀點。轉(zhuǎn)載的所有的文章、圖片、音/視頻文件等資料的版權(quán)歸版權(quán)所有權(quán)人所有。本站采用的非本站原創(chuàng)文章及圖片等內(nèi)容無法一一聯(lián)系確認版權(quán)者。如涉及作品內(nèi)容、版權(quán)和其它問題,請及時通過電子郵件或電話通知我們,以便迅速采取適當措施,避免給雙方造成不必要的經(jīng)濟損失。聯(lián)系電話:010-82306118;郵箱:aet@chinaaet.com。