- 您现在的位置：买卖IC网 > PDF目录98288 > TS421-8IQT (STMICROELECTRONICS) 0.367 W, 1 CHANNEL, AUDIO AMPLIFIER, DSO8 PDF资料下载
参数资料
| 型号： | TS421-8IQT |
| 厂商： | STMICROELECTRONICS |
| 元件分类： | 音频／视频放大 |
| 英文描述： | 0.367 W, 1 CHANNEL, AUDIO AMPLIFIER, DSO8 |
| 封装： | MLFP-8 |
| 文件页数： | 21/32页 |
| 文件大小： | 1000K |
| 代理商： | TS421-8IQT |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页当前第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页
TS419-TS421
28/32
The efficiency is the ratio between the output
power and the power supply
The maximum theoretical value is reached when
Vpeak = Vcc, so
s Decoupling of the circuit
Two capacitors are needed to bypass properly the
TS419/TS421. A power supply bypass capacitor
CS and a bias voltage bypass capacitor CB.
CS has particular influence on the THD+N in the
high frequency region (above 7kHz) and an
indirect influence on power supply disturbances.
With
1F,
you
can
expect
similar
THD+N
performances to those shown in the datasheet.
In the high frequency region, if CS is lower than
1F, it increases THD+N and disturbances on the
power supply rail are less filtered.
On the other hand, if CS is higher than 1F, those
disturbances on the power supply rail are more
filtered.
CB has an influence on THD+N at lower
frequencies, but its function is critical to the final
result of PSRR (with input grounded and in the
lower frequency region).
If CB is lower than 1F, THD+N increases at lower
frequencies and PSRR worsens.
If CB is higher than 1F, the benefit on THD+N at
lower frequencies is small, but the benefit to PSRR
is substantial.
Note that CIN has a non-negligible effect on PSRR
at lower frequencies. The lower the value of CIN,
the higher the PSRR.
s Wake-up Time: T
WU
When standby is released to put the device ON,
the bypass capacitor CB will not be charged
immediatly. As CB is directly linked to the bias of
the amplifier, the bias will not work properly until
the CB voltage is correct. The time to reach this
voltage is called wake-up time or TWU and typically
equal to:
TWU=0.15xCB (s) with CB in F.
Due to process tolerances, the range of the
wake-up time is :
0.12xCb < TWU < 0.18xCB (s) with CB in F
Note : When the standby command is set, the time
to put the device in shutdown mode is a few
microseconds.
s Pop performance
Pop performance is intimately linked with the size
of the input capacitor Cin and the bias voltage
bypass capacitor CB.
The size of CIN is dependent on the lower cut-off
frequency and PSRR values requested. The size
of CB is dependent on THD+N and PSRR values
requested at lower frequencies.
Moreover, CB determines the speed with which the
amplifier turns ON. The slower the speed is, the
softer the turn ON noise is.
The charge time of CB is directly proportional to
the internal generator resistance 150k
..
Then, the charge time constant for CB is
τ
B = 150kxCB (s)
As CB is directly connected to the non-inverting
input (pin 2 & 3) and if we want to minimize, in
amplitude and duration, the output spike on Vout1
(pin 5), CIN must be charged faster than CB. The
equivalent charge time constant of CIN is:
τ
IN = (Rin+Rfeed)xCIN (s)
Thus we have the relation:
τ
IN < τB (s)
Proper respect of this relation allows to minimize
the pop noise.
Remark : Minimizing CIN and CB benefits both the
pop phenomena, and the cost and size of the
application.
s Application : Differential inputs BTL power
amplifier.
The schematic on figure 98, shows how to design
the TS419/21 to work in a differential input mode.
The gain of the amplifier is:
In order to reach optimal
performances of the differential function, R1 and
R2 should be matched at 1% max.
Vcc
4
V
ply
sup
P
PEAK
OUT
π
=
η
%
5
.
78
4
=
π
1
2
VDIFF
R
2
G
=
相关PDF资料 |
PDF描述 |
|---|---|
| TS421-8IST | 0.367 W, 1 CHANNEL, AUDIO AMPLIFIER, PDSO8 |
| TS421IDT | 0.367 W, 1 CHANNEL, AUDIO AMPLIFIER, PDSO8 |
| TS421ID | 0.367 W, 1 CHANNEL, AUDIO AMPLIFIER, PDSO8 |
| TS421IQT | 0.367 W, 1 CHANNEL, AUDIO AMPLIFIER, DSO8 |
| TS421IST | 0.367 W, 1 CHANNEL, AUDIO AMPLIFIER, PDSO8 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| TS421ID | 功能描述:音频放大器 360mW Mono Amplifier RoHS:否 制造商:STMicroelectronics 产品:General Purpose Audio Amplifiers 输出类型:Digital 输出功率: THD + 噪声: 工作电源电压:3.3 V 电源电流: 最大功率耗散: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:TQFP-64 封装:Reel |
| TS421IDT | 功能描述:音频放大器 360mW Mono Amplifier RoHS:否 制造商:STMicroelectronics 产品:General Purpose Audio Amplifiers 输出类型:Digital 输出功率: THD + 噪声: 工作电源电压:3.3 V 电源电流: 最大功率耗散: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:TQFP-64 封装:Reel |
| TS421IQT | 功能描述:音频放大器 360mW mono audio amp RoHS:否 制造商:STMicroelectronics 产品:General Purpose Audio Amplifiers 输出类型:Digital 输出功率: THD + 噪声: 工作电源电压:3.3 V 电源电流: 最大功率耗散: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:TQFP-64 封装:Reel |
| TS421IST | 功能描述:音频放大器 360mW Mono Amplifier RoHS:否 制造商:STMicroelectronics 产品:General Purpose Audio Amplifiers 输出类型:Digital 输出功率: THD + 噪声: 工作电源电压:3.3 V 电源电流: 最大功率耗散: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:TQFP-64 封装:Reel |
| TS4264 | 制造商:TSC 制造商全称:Taiwan Semiconductor Company, Ltd 功能描述:5V/150mA Fixed-Voltage Ultra Low LDO |
发布紧急采购，3分钟左右您将得到回复。