參數資料
型號: TPA721DGN
廠商: TEXAS INSTRUMENTS INC
元件分類: 音頻/視頻放大
英文描述: 0.7 W, 1 CHANNEL, AUDIO AMPLIFIER, PDSO8
封裝: GREEN, PLASTIC, MSOP-8
文件頁數: 6/26頁
文件大?。?/td> 663K
代理商: TPA721DGN
www.ti.com
I
DD(RMS) +
2V
P
p
R
L
P
SUP + VDD
I
DD(RMS) +
V
DD 2VP
p
R
L
Efficiency +
P
L
P
SUP
where
P
L +
V
L(RMS)
2
R
L
+
Vp
2
2R
L
V
L(RMS) +
V
P
2
(3)
Efficiency of a BTL configuration
+
p
V
P
4V
DD
+
p
2 P
LRL
1 2
4V
DD
(4)
TPA721
SLOS231E – NOVEMBER 1998 – REVISED JUNE 2004
APPLICATION INFORMATION (continued)
Table 1 employs Equation 4 to calculate efficiencies for three different output power levels. The efficiency of the
amplifier is quite low for lower power levels and rises sharply as power to the load is increased, resulting in a
nearly flat internal power dissipation over the normal operating range. The internal dissipation at full output power
is less than in the half power range. Calculating the efficiency for a specific system is the key to proper power
supply design.
Table 1. Efficiency vs Output Power in 3.3-V, 8-
BTL Systems
INTERNAL
OUTPUT POWER
EFFICIENCY
PEAK VOLTAGE
DISSIPATION
(W)
(%)
(V)
(W)
0.125
33.6
1.41
0.26
0.25
47.6
2.00
0.29
0.375
58.3
2.45(1)
0.28
(1)
High-peak voltage values cause the THD to increase.
A final point to remember about linear amplifiers (either SE or BTL) is how to manipulate the terms in the
efficiency equation to utmost advantage when possible. In Equation 4, VDD is in the denominator. This indicates
that as VDD goes down, efficiency goes up.
14
相關PDF資料
PDF描述
TPA721DGNR 0.7 W, 1 CHANNEL, AUDIO AMPLIFIER, PDSO8
TPA721DR 0.7 W, 1 CHANNEL, AUDIO AMPLIFIER, PDSO8
TPA721DG4 0.7 W, 1 CHANNEL, AUDIO AMPLIFIER, PDSO8
TPA721DGNG4 0.7 W, 1 CHANNEL, AUDIO AMPLIFIER, PDSO8
TPA721DGNRG4 0.7 W, 1 CHANNEL, AUDIO AMPLIFIER, PDSO8
相關代理商/技術參數
參數描述
TPA721DGNG4 功能描述:音頻放大器 Mono Class-AB w/Active HIgh Shtdwn RoHS:否 制造商:STMicroelectronics 產品:General Purpose Audio Amplifiers 輸出類型:Digital 輸出功率: THD + 噪聲: 工作電源電壓:3.3 V 電源電流: 最大功率耗散: 最大工作溫度: 安裝風格:SMD/SMT 封裝 / 箱體:TQFP-64 封裝:Reel
TPA721DGNR 功能描述:音頻放大器 700mW Lw V Audio RoHS:否 制造商:STMicroelectronics 產品:General Purpose Audio Amplifiers 輸出類型:Digital 輸出功率: THD + 噪聲: 工作電源電壓:3.3 V 電源電流: 最大功率耗散: 最大工作溫度: 安裝風格:SMD/SMT 封裝 / 箱體:TQFP-64 封裝:Reel
TPA721DGNRG4 功能描述:音頻放大器 Mono Class-AB w/Active HIgh Shtdwn RoHS:否 制造商:STMicroelectronics 產品:General Purpose Audio Amplifiers 輸出類型:Digital 輸出功率: THD + 噪聲: 工作電源電壓:3.3 V 電源電流: 最大功率耗散: 最大工作溫度: 安裝風格:SMD/SMT 封裝 / 箱體:TQFP-64 封裝:Reel
TPA721DR 功能描述:音頻放大器 700mW Lw V Audio RoHS:否 制造商:STMicroelectronics 產品:General Purpose Audio Amplifiers 輸出類型:Digital 輸出功率: THD + 噪聲: 工作電源電壓:3.3 V 電源電流: 最大功率耗散: 最大工作溫度: 安裝風格:SMD/SMT 封裝 / 箱體:TQFP-64 封裝:Reel
TPA721DRG4 功能描述:音頻放大器 Mono Class-AB w/Active HIgh Shtdwn RoHS:否 制造商:STMicroelectronics 產品:General Purpose Audio Amplifiers 輸出類型:Digital 輸出功率: THD + 噪聲: 工作電源電壓:3.3 V 電源電流: 最大功率耗散: 最大工作溫度: 安裝風格:SMD/SMT 封裝 / 箱體:TQFP-64 封裝:Reel