- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄30752 > LM4817MH/NOPB (NATIONAL SEMICONDUCTOR CORP) 1.5 W, 2 CHANNEL, AUDIO AMPLIFIER, PDSO28 PDF資料下載
參數(shù)資料
| 型號： | LM4817MH/NOPB |
| 廠商： | NATIONAL SEMICONDUCTOR CORP |
| 元件分類： | 音頻／視頻放大 |
| 英文描述： | 1.5 W, 2 CHANNEL, AUDIO AMPLIFIER, PDSO28 |
| 封裝： | 4.40 MM, TSSOP-28 |
| 文件頁數(shù)： | 4/21頁 |
| 文件大?。?/td> | 1119K |
| 代理商： | LM4817MH/NOPB |
Application Information
BRIDGE CONFIGURATION EXPLANATION
As shown in Figure 1, the LM4817 consists of two pairs of
operational amplifiers, forming a two-channel (channel A and
channel B) stereo amplifier. (Though the following discusses
channel A, it applies equally to channel B.) External resistors
R
f and Ri set the closed-loop gain of Amp1A, whereas two
internal 20k
resistors set Amp2A’s gain at -1. The LM4817
drives a load, such as a speaker, connected between the two
amplifier outputs, -OUTA and +OUTA.
Figure 1 shows that Amp1A’s output serves as Amp2A’s
input. This results in both amplifiers producing signals iden-
tical in magnitude, but 180 out of phase. Taking advantage
of this phase difference, a load is placed between -OUTA
and +OUTA and driven differentially (commonly referred to
as "bridge mode"). This results in a differential gain of
A
VD =2x(Rf /Ri)
(1)
Bridge mode amplifiers are different from single-ended am-
plifiers that drive loads connected between a single amplifi-
er’s output and ground. For a given supply voltage, bridge
mode has a distinct advantage over the single-ended con-
figuration: its differential output doubles the voltage swing
across the load. This produces four times the output power
when compared to a single-ended amplifier under the same
conditions. This increase in attainable output power as-
sumes that the amplifier is not current limited or that the
output signal is not clipped. To ensure minimum output sig-
nal clipping when choosing an amplifier’s closed-loop gain,
refer to the Audio Power Amplifier Design section.
Another advantage of the differential bridge output is no net
DC voltage across the load. This is accomplished by biasing
channel A’s and channel B’s outputs at half-supply. This
eliminates the coupling capacitor that single supply, single-
ended amplifiers require. Eliminating an output coupling ca-
pacitor in a single-ended configuration forces a single-supply
amplifier’s half-supply bias voltage across the load. This
increases internal IC power dissipation and may perma-
nently damage loads such as speakers.
POWER DISSIPATION
Power dissipation is a major concern when designing a
successful single-ended or bridged amplifier. Equation (2)
states the maximum power dissipation point for a single-
ended amplifier operating at a given supply voltage and
driving a specified output load
P
DMAX =(VDD)
2 /(2
π2 R
L) Single-Ended
(2)
However, a direct consequence of the increased power de-
livered to the load by a bridge amplifier is higher internal
power dissipation for the same conditions.
20078101
* Refer to the section Proper Selection of External Components, for a detailed discussion of CB size.
FIGURE 1. Typical Audio Amplifier Application Circuit
Pin out shown for the LLP package. Refer to the Connection Diagrams for the pinout of the TSSOP package.
LM4817
www.national.com
12
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| LM4818M/NOPB | 0.35 W, 1 CHANNEL, AUDIO AMPLIFIER, PDSO8 |
| LM4820MMX-6 | 1 W, 1 CHANNEL, AUDIO AMPLIFIER, PDSO8 |
| LM4820MMX-6/NOPB | 1 W, 1 CHANNEL, AUDIO AMPLIFIER, PDSO8 |
| LM4820MX-6/NOPB | 1 W, 1 CHANNEL, AUDIO AMPLIFIER, PDSO8 |
| LM4820MX-6 | 1 W, 1 CHANNEL, AUDIO AMPLIFIER, PDSO8 |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| LM4817MHX/NOPB | 功能描述:IC AMP AUDIO PWR 1.5W AB 28TSSOP RoHS:是 類別:集成電路 (IC) >> 線性 - 音頻放大器 系列:Boomer® 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標(biāo)準(zhǔn)包裝:2,500 系列:DirectDrive® 類型:D 類 輸出類型:1-通道（單聲道），帶立體聲耳機 在某負(fù)載時最大輸出功率 x 通道數(shù)量:930mW x 1 @ 8 歐姆; 40mW x 2 @ 16 歐姆 電源電壓:2.7 V ~ 5.5 V 特點:消除爆音，差分輸入，I²C，靜音，關(guān)閉，音量控制 安裝類型:表面貼裝 供應(yīng)商設(shè)備封裝:25-WLP（2.09x2.09） 封裝/外殼:25-WFBGA，WLCSP 包裝:帶卷 (TR) 其它名稱:MAX97000EWA+T-ND |
| LM4818 | 制造商:NSC 制造商全稱:National Semiconductor 功能描述:350mW Audio Power Amplifier with Shutdown Mode |
| LM4818M | 制造商:NSC 制造商全稱:National Semiconductor 功能描述:350mW Audio Power Amplifier with Shutdown Mode |
| LM4818M/NOPB | 功能描述:IC AMP AUDIO PWR .35W MONO 8SOIC RoHS:是 類別:集成電路 (IC) >> 線性 - 音頻放大器 系列:Boomer® 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標(biāo)準(zhǔn)包裝:2,500 系列:DirectDrive® 類型:H 類 輸出類型:耳機，2-通道（立體聲） 在某負(fù)載時最大輸出功率 x 通道數(shù)量:35mW x 2 @ 16 歐姆 電源電壓:1.62 V ~ 1.98 V 特點:I²C，麥克風(fēng)，靜音，短路保護(hù)，音量控制 安裝類型:表面貼裝 供應(yīng)商設(shè)備封裝:25-WLP（2.09x2.09） 封裝/外殼:25-WFBGA，WLCSP 包裝:帶卷 (TR) |
| LM4818MABD | 功能描述:BOARD EVALUATION LM4818MA RoHS:否 類別:編程器，開發(fā)系統(tǒng) >> 評估板 - 音頻放大器 系列:Boomer® 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標(biāo)準(zhǔn)包裝:1 系列:- |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。