| 主题：意法半导体的音频运放/模拟开关/电平转换/电源管理及接口新产品系列在移动电话中的应用 |
| 在线问答： |
| [问：wt3567938] |
音频运放的带宽是决定通话质量的重要因素吗？最大的带宽是多少？ |
| [答：Tony] |
对于通话质量，带宽在0~8KHz足够，ST的音频运放最大带宽为22KHz |
[2005-12-16 10:46:50] |
| [问：xcharlie] |
贵公司的模拟开关应用于移动电话的哪一部分之中？其性能和其它类似产品相比有什么特点吗？ |
| [答：Jason] |
你好，模拟开关主要用在:
1. 切换音频输入输出(voide codec/MP3/melody.... to speak/earjet/receiver)，
2. 数据输出方面(USB/MP3/UART/Voide)
ST的产品与其他类似产品相比主要有以下特点：
1. 非常低的导通电阻 （0.5ohm）
2. 高数据带宽(50~100Mhz)
3. 非常小的封装 |
[2005-12-16 10:47:13] |
| [问：wmtju] |
我知道贵公司有一款TS4994的芯片，它和TS4984有什么不同？谢谢！ |
| [答：Zipper] |
TS4994 is an differential input Mono audio amp, TS4984 is a stereo audio
amp with single input |
[2005-12-16 10:47:48] |
| [问：supernemocn] |
音频放大器对电源和地有什么特殊要求？ |
| [答：Tony] |
在设计中需要注意电源纹波对音频运放的影响。可以选择使用PSRR较高的产品。差分运放的PSRR较高 |
[2005-12-16 10:48:16] |
| [问：mazha] |
电平转换在一边有电一边没电时，是否会有漏电现象？ |
| [答：Jason] |
不会，因为ST的电平转换在输入输出端都有power down保护功能。 |
[2005-12-16 10:48:20] |
| [问：hawkzeus] |
全差分输入的音频功放有什么特点和优势? |
| [答：Zipper] |
use full differential audio amp our PSRR is quite high, around 100db,
it is very important for mobile phone ; at the mean time, use differential
input designer do not worry about the input disturb |
[2005-12-16 10:50:17] |
| [问：wt3567938] |
如何使电池的待机时间更长？ |
| [答：Jason] |
很多方面会影响电池的待机，通常来讲是各个模块的核电压/IO电压越低，功耗就越小，待机就会比较长。例如飞利浦的手机待机都比较长，因为他们采用的低电压器件较多（<1.8V） |
[2005-12-16 10:51:05] |
| [问：shirley-peng] |
如何看数字功放市场？ |
| [答：Zipper] |
it is booming now. but a lot of customer did not use it in the past,
so they worry about from technical side . most of them are wating for
the marketing and end customer request |
[2005-12-16 10:53:08] |
| [问：KINLYLAY] |
什么是Phantom Ground ?能解释一下吗?它有什么优点? |
| [答：Tony] |
PHANTOM GROUND是指我们的芯片可以提供直流的偏置电压从而在连接耳机的电路输出上不需要用隔直电容. 可以简化PCB设计降低成本.在上只需移初原来的隔直电容将耳机的连接引脚直接接到芯片上即可 |
[2005-12-16 10:58:06] |
| [问：qzxu] |
ST的音频功放是采用D类放大吗?它的效率能达到多高? |
| [答：Tony] |
TS4962M 是D类功放，效率最大可达90% |
[2005-12-16 10:59:22] |
| [问：kkwd] |
ST的模拟开关是NO,NC还是什么类型? |
| [答：Jason] |
open/close 是由控制pin决定的，我们不为模拟开关定义NO/NC |
[2005-12-16 10:59:28] |
| [问：qzxu] |
ST的音频功放有没有全数字的? |
| [答：Tony] |
ST的StandIC部门没有全数字音频功放 |
[2005-12-16 11:00:27] |
| [问：tech0013] |
请问模拟开关STG3699的带宽能达到多少?导通电阻的平坦度如何? |
| [答：Jason] |
50Mhz (-3db)
0.15ohm (Vcc=2.7~4.3V) |
[2005-12-16 11:01:42] |
| [问：zodiac_mwl] |
电平转换器是否是双向的(从低到高和从高到低)?是否需要双电源? |
| [答：Jason] |
74VCX （16bit）和ST6G(6bit)系列是双向的
ST1G/4G是单向的 (1bit/4bit)
都是需要双电源 |
[2005-12-16 11:03:51] |
| [问：kongsy] |
请问模拟开关是否是单电源工作?控制信号如何处理?需要多大的驱动力度? |
| [答：Jason] |
1.单电源
2.用0/1控制信号控制开关的导通通道
3.“驱动力度”？ |
[2005-12-16 11:05:15] |
| [问：kkwd] |
国内的代理商是哪家?方便的话给我发些SPEC |
| [答：Tony] |
Arrow 和 Solomn是ST在国内主要代理商 |
[2005-12-16 11:05:30] |
| [问：zodiac_mwl] |
ST的模拟开关除了用在手机上,还能用在什么地方? |
| [答：Jason] |
还可以用在其他移动设备上，任何需要模拟/数字信号切换的应用 |
[2005-12-16 11:06:37] |
| [问：worea] |
请介绍D类功率放大器的EMI性能.它对手机的性能有何影响? |
| [答：Tony] |
ST 对EMI测试由完备测试报告，您可以直接和我们联系获得。 |
[2005-12-16 11:08:30] |
| [问：jesuisYC] |
现在很多都采用差分信号传输,请问差分信号传输比单端信号传输有何好处? |
| [答：Zipper] |
Use differential input it is not sensitive for RF disturb and our PSRR
is quite high, 100db, it is very important for mobile phone application |
[2005-12-16 11:11:01] |
| [问：ylkan] |
pop-click什么意思？ST1G3234的最大速率380MBPS是M bit吗？请问30uVrms中的单位是什么意思? |
| [答：Jason] |
1. 是指音频切换过程中出现的短暂的“波”噪音 - 例如receiver切换到免提（speak）时
2. 是Mbit
3. （指那个产品？) |
[2005-12-16 11:11:19] |
| [问：fanlun] |
ST的电平转换器有缓冲器吗?它的传输时延有多大?对系统的时序影响有多大?应如何考虑? |
| [答：Zipper] |
Internally there is a buffer, but the delay value is quite small, only
several ns, e. g 4~5 ns. Compare with system delay, designer can ignore
it. It will not affect the system sequency |
[2005-12-16 11:13:04] |
| [问：tech0013] |
多路模拟开关的通路隔离度和电阻的匹配的性能如何? |
| [答：Jason] |
以STG3699为例：
OIRR （Off Isolation）= -64 dB
(VS= 1VRMS f= 100KHz)
?RON ON = 0.06ohm
(Vcc = 2.7 VS @ RON Max IS=100mA) |
[2005-12-16 11:15:04] |
| [问：andylily] |
power down 是自动的吗 |
| [答：Jason] |
是的 |
[2005-12-16 11:15:17] |
| [问：shirley-peng] |
模拟功放IC的市场前景会怎样，现在国产功放的成本甚低，ST对这个市场如何看待 |
| [答：Zipper] |
Analog audio amp marketing will continue to increase. Even there are
some Chinese / Taiwan company can provide some product, but
if you compare with the key parameter / product line / support, you will
find ST is one of the best provider. With St’s technical / product we
can provide total solution for portable application |
[2005-12-16 11:15:58] |
| [问：worea] |
音频功放的带宽有多宽?采用ST的音频功放,它的总失真能达到多少dB? |
| [答：Zipper] |
for our audio amp, normally the BW is from 0Hz to 22Khz. for our SNR
it is about 85~ 100 db depend on different product. for THD, all of our
class AB product is no more than 0.1% as typical value |
[2005-12-16 11:17:51] |
| [问：supernemocn] |
贵公司的DC-DC芯片的最小输出电压是多少？我想用0.6V的电压，不知道有没有这样的芯片 |
| [答：Francesco] |
The minimum Vout is 0.8V
The power voltage supply is from 0.3V to 7V
It is not possible to provide 0.6V as Vout. |
[2005-12-16 11:20:39] |
| [问：tanglidi] |
数字功放的技术支持是ST的代理商还是你们自己?联系方法是.... |
| [答：Zipper] |
in shanghai , beijing and shenzhe we have FAE team .
for class D audio amp, we will support it now directlly as it is the new
product.
you can call ST shanghai office, 021 3405 4688, and then transfer to Tony
or Zipper.
if you are in Shen zhen, you can call shenzhen office 0755 86012124 transfer
to Leon
or beijing office 010 8809 7398 transfer to William |
[2005-12-16 11:21:48] |
| [问：k_houqing] |
请介绍模拟开关在高频和音频的失真性能?能否用于视频信号的关断? |
| [答：Jason] |
THD （Total Harmonic Distortion）= 0.03%
(Vcc=2.3-4.3 RL= 600? VIN= 2VPP f= 20Hz to 20kHz)
是否能用于视频切换取决于视频信号的带宽频率，ST现在量产产品中最大支持的带宽为250Mhz （STG3157, single SPDT Analog
switch） |
[2005-12-16 11:23:00] |
| [问：zw168] |
功率管理是否具有动态功率管理功能?电源效率能达到多高? |
| [答：Francesco] |
Could you pls clarify which specific device are you talking about? |
[2005-12-16 11:24:11] |
| [问：jesuisYC] |
USB2.0和USB OTG有何区别?OTG的含义是什么? |
| [答：Francesco] |
USB (Universal serial Bus)
OTG (On the go)
These two device are comunication standard.
UBS is a "simple" connector that does not allow the device to be host
unless we are talking about a PC.
The OTG, allows the devices such us Mobile Phone, PDA, Camera, to became
Host and thus share date with other devices without using a PC. |
[2005-12-16 11:26:54] |
| [问：zwzhb] |
现在的手机朝单片解决方案发展,ST的标准产品有何竞争优势? |
| [答：Zipper] |
except chip set, you can find all the other Stand IC product which one
needed by application.
in Asia we technical support team locate in Beijing, Shanghai and Shenzhen,
who can provide support to CTM at the first time. |
[2005-12-16 11:29:01] |
| [问：shipyan1] |
ST的双模式电源能否驱动手机的主副两个显示器的LED背景光? |
| [答：Francesco] |
Our Devices for the backlight are able to drive a number of LEDs in
series configuration.
The output is just one. |
[2005-12-16 11:29:23] |
| [问：andylily] |
能详细解释一下power down 功能吗？ |
| [答：Francesco] |
For which device? |
[2005-12-16 11:29:49] |
| [问：tech0013] |
ST的模拟开关和Siliconix的DG2015相比,有何特点和优势? |
| [答：Jason] |
一样的功能，但有以下主要区别 STG3699BVTR DG
2015
=======================================
Ron 0.40ohm 0.85ohm
Vcc max 4.3V 3.3V
Package 2.6x1.8mm 3.0x3.0mm
所以STG3699更适合于需要一下几点的应用：
1）更低导通电阻
2）宽供电范围
3）小尺寸封装 |
[2005-12-16 11:29:59] |
| [问：mahongtao] |
模拟开关有没有5V--15V的产品?
什么型号? |
| [答：Zipper] |
until to now we do not have this kind of product. our analog switch
is for low Vcc, auido or video signal application |
[2005-12-16 11:30:03] |
| [问：kongsy] |
ST模拟开关的闭合与断开所需时间有多快? |
| [答：Jason] |
以STG3699为例：
Ton = 40ns (Vcc 3.3~4.3V)
Toff = 15ns (Vcc 3.3~4.3V) |
[2005-12-16 11:31:41] |
| [问：fanlun] |
ST的电平转换器对电源的加电顺序有何影响?应如何考虑? |
| [答：Zipper] |
CTM should power on those 2 differet Vcc first, and then to transfer
data. for the 2 Vcc, there is no special request for the sequesce |
[2005-12-16 11:31:44] |
| [问：hawkzeus] |
请介绍Pop/click 抑制电路的电路结构.它和无Pop/click 电路相差大吗? |
| [答：Zipper] |
pop&click circuit is one of ST"s patent, it will help to remove
the pop and click noise during power on or power down. this knd of noise
is not acceptable in some high end aplication |
[2005-12-16 11:34:04] |
| [问：chenkexian] |
请介绍电平转换器的过压容限输入性能和输出的精度. |
| [答：Jason] |
e.g. 74VCXH1632245TBR
1. VI (DC Input Voltage) = -0.5 to +4.6 V
2. （指电压还是电流？） |
[2005-12-16 11:36:16] |
| [问：shirley-peng] |
ST的功放与PHI的来比，有什么好？ |
| [答：Zipper] |
as we know, Stand IC can provide low voltage audio amp, but in ST the
other div can provide high voltage audio amp which one can use in home
auido system or car audio system. for PHI they do not have low Vcc audio
amp. if you want to know more about high Vcc audio amp you can contact
ST local office to get more information |
[2005-12-16 11:36:36] |
| [问：Jenny_lyl_liu] |
TS4909 会卖多少钱？ |
| [答：Zipper] |
forecast is about 0.3$ |
[2005-12-16 11:37:14] |
| [问：andylily] |
st的模拟开关的最大切换速度是多少？ |
| [答：Jason] |
Ton = 40ns (Vcc 3.3~4.3V)
Toff = 15ns (Vcc 3.3~4.3V) |
[2005-12-16 11:37:58] |
| [问：chhf] |
请问有没有这样的模拟开关:类似机械式的单刀双掷开关,需要两路. |
| [答：Jason] |
STG3684 - 双路单刀双掷模拟开关 |
[2005-12-16 11:38:38] |
| [问：jesuisYC] |
SMIA代表什么?是一个什么样的项目? |
| [答：Francesco] |
SMIA (Standard Mobile Imaging Architecture)
The CCP (Compact Camera POrt decoder) is a standard of decodification
of data coming from the Camera to the Baseband.
The SMIA is complaint with CCP1.0 and CCP2.0 specification.
It is used to deserialize the data coming form SERIAL CAMERA SENSOR and
transfer them to the PARALLEL BASEBAND.
It is clear that in case the ctms use the SERIAL CAMERA SENSOR this device
can not be promoted.
For more info pls check into the SMIA web site. Search for "SMIA" in Google. |
[2005-12-16 11:39:22] |
| [问：spsonic] |
16位双电平转换器件有没有tssop封装的？ |
| [答：Jason] |
有TSSOP (74VCXH1632245TTR)，但在移动设备中建议使用uTFBGA42的小封装 (74VCXH1632245TBR)
|
[2005-12-16 11:40:03] |
| [问：ylkan] |
关于噪声定义，uVrms，V/Hz开方，还有dBc/Hz,各有什么不同 |
| [答：Zipper] |
uVrms is the focus on power level
V/H 开方 is focus on the different noise level on different frequency
dBc/Hz is another type, which one transfer voltage level to db
for all of these definiation depending on different function block request
in system block |
[2005-12-16 11:40:50] |
| [问：zwzhb] |
USB OTG传输视频如照相图像的速率有多快? |
| [答：Francesco] |
As you know there are three kind of speed supported by the USB.
Low speed: 1.5Mbps
Full Speed : 12 Mbps
High Speed: ~400Mbps
No matter if it is a transfer of Video,Audio,etc...data.
Our Devices can support Low speed and Full Speed. |
[2005-12-16 11:44:15] |
| [问：liduming] |
芯片标识ST S35，封装SOT-23，3个管脚，请问这个芯片的具体型号？谢谢 |
| [答：Tony] |
S35 只是生产日期的标识。从它无法得到具体型号。
您可以讯问芯片代理商。谢谢 |
[2005-12-16 11:46:29] |
| [问：worea] |
ST的音频功放和National的LM4854相比,有何优势? |
| [答：Zipper] |
LM4854 integrate 3D function. for ST our TS4956 have all the function
as LM4854 except 3D function.
for 3D function product, we think different customer has different design
idea. for ST we prefer to do it a ASSP product. |
[2005-12-16 11:47:04] |
| [问：chenkexian] |
ST的电平转换器和TI的单电源逻辑电平转换器SN74AUP1T97,有何特色? |
| [答：Jason] |
这两个产品具有非常不同的功能，我需要具体看一下TI的这个新产品 |
[2005-12-16 11:47:11] |
| [问：fanlun] |
电平转换器有没有对延迟的补偿功能? |
| [答：Zipper] |
no, because the dealy is too small. it will not affect the system performance. |
[2005-12-16 11:47:44] |
| [问：shirley-peng] |
可否留下专家的EMAIL |
| [答：Zipper] |
if you have any technical problem or want to know our product feature
you can send mail to
zipper.zhang@st.com
or
tony.jiao@st.com |
[2005-12-16 11:49:31] |
| [问：hawkzeus] |
ST的TS4985需要输出耦合电容器吗?如果需要,电容量要多大? |
| [答：Tony] |
对于BTL连接方式，无需输出耦合电容 |
[2005-12-16 11:50:33] |
| [问：wmtju] |
差分输入的音频放大器如果输出电压偏小，如何调整？ |
| [答：Tony] |
建议调节放大倍数，如果输出还是过小，建议检测输入和输出端信号 |
[2005-12-16 11:51:21] |
| [问：shipyan1] |
ST的升压转换器STCF01对每个LED电流的匹配如何进行调节?能达到几%? |
| [答：Francesco] |
The STCF01 is Step up PWM.
The current provided in the 4 LED in continuosly monitored by the FB pin
(feedback pin).
By using an internal circuit the device is able to monitor and adjust
the current on the LEDs. |
[2005-12-16 11:51:31] |
| [问：ss2000] |
关于STUSB02E，请解释一下"D+ and D- can be shared with
other serial protocol" |
| [答：Zipper] |
as the different signal it can use for STUSB02 or can be used for the
other IC which one also use differential signal |
[2005-12-16 11:52:37] |
| [问：zw168] |
ST的闪光灯电源能保证照相手机的连续拍照吗?或者说是摄像? |
| [答：Francesco] |
The device is able to take as much shoot as decided by the Baseband.
The device is a "simple" switch current driven.
THe SHDN (Shut down) pin activate and disactivate the device based on
the imput coming from the baseband. |
[2005-12-16 11:57:07] |
| [问：w.liu] |
闪光灯升压电路是否可以用于其他DC-DC电路中？ |
| [答：Francesco] |
The device as the maximum rate in terms of current and voltage.
Thus, if other application use LEDs having specification suitable for
our device, there is no problem to use it. |
[2005-12-16 12:00:24] |
| [问：w.liu] |
闪光灯升压电路可以长时间的连续工作吗？ |
| [答：Francesco] |
Our Camera flash have two main function.
Flash Mode
Torch Mode
In the torch mode the LEDs can be kept ON as much as the battery support
it. |
[2005-12-16 12:03:45] |
| [问：RobitFeng] |
ST有沒有單通道的USB Power switch?型號是什么?謝謝 |
| [答：Jason] |
STMPS2242, 明年Q1提供样品 |
[2005-12-16 12:04:08] |
| 非在线问答： |
| [问：] |
ST 电平转换器是否有延时功能？？ |
| [答：] |
有，即逻辑本身的输入/输出的延时：e.g. 74VCXH1632245 - 4.4ns, 74VCXHQ163245
- 6ns。具体可参考相应的data sheet |
| [问：] |
STBC08的价格是多少？How much is the price for STBC08 |
| [答：] |
The price is based on several parameeter such us the Customer,
the quantity involved, market price. |
| [问：] |
ST数字功放的成本怎么控制？ |
| [答：] |
without the filter circuit, the cost is only IC itself and
the external Cap and Resistor. |
| [问：] |
ST有哪些汽车功放IC？ |
| [答：] |
this kind of Power Audio Amp belong to another Div, APG,
you can check with our local office for detail information |
| [问：] |
TS4985你们的样品有没有 |
| [答：] |
yes, we have |
| [问：] |
电平转换器的上升和下降时间有多少? |
| [答：] |
（见下数值表） |
| [问：] |
电平转换器的输出是否在两个电源都达到有效水平之前有保持在高阻抗状态的功能? |
| [答：] |
有，即"power done protection on input/output sides" |
| [问：] |
电源管理有什么新的产品 |
| [答：] |
STw4102 |
| [问：] |
耳机放大器和扬声器放大器是否集成在一块芯片内? |
| [答：] |
we have this kind of product which one integrate headphone
driver and speaker driver |
| [问：] |
国内代理商里功放占优势的是哪家？ |
| [答：] |
Solomon, Arrow |
| [问：] |
模拟开关的开关时间是多少ns |
| [答：] |
Ton = 40ns(Vcc 3.3~4.3V)
Toff = 15ns (Vcc 3.3~4.3V) |
| [问：] |
模拟开关是什么封装? |
| [答：] |
DFN16 2.6x1.8x0.55mm, QFN16 2.5x2.5x0.55mm, QFN16 3x3x0.9mm,
DFN10 2.3x2.0x0.55mm |
| [问：] |
请教ST应用工程师，能否详细介绍各个器件的典型应用呢？ |
| [答：] |
yes, you can contact with us. We can provide reference design,
function block, application notes |
| [问：] |
请介绍模拟开关在导通时的电荷注入性能.它会影响到手机那方面的性能? |
| [答：] |
when Switch is Enabled Data Port Capacitance typical value
is 84pF @Vcc=3.3, it is very small. As audio signal BW is no more than
22KHz, so charge / discharge this cap will not affect audio performance
in mobile phone |
| [问：] |
请问ST的模拟开关的导通和关断的电阻比能达到多少dB? |
| [答：] |
OIRR (off isolation) = -64dB @ Vs=1Vrms, f=100KHz Crosstalk
= -54dB @ Vs=1Vrms, f=100KHz |
| [问：] |
请问贵公司现在可以申请样品么 |
| [答：] |
what kind of samples…? |
| [问：] |
请专家介绍一下模拟开关关断时的噪音性能. |
| [答：] |
OIRR (off isolation) = -64dB @ Vs=1Vrms, f=100KHz Crosstalk
= -54dB @ Vs=1Vrms, f=100KHz |
| [问：] |
闪光灯电源能对多大的电容进行充电?充电速度有多快? For Flash application,
how much is is the maxim cap load..? How fast is the charge time..? |
| [答：] |
The STCF01 is able to provide up to 300mA, and Vsw is from
0.3 to 20V. The charging time depend on the PMIC. In fact the device is
just a driver for the LED wich receive the input from the PMIC to turn
ON/OFF the LEDs. |
| [问：] |
手机用电源的波纹系数能达到多少才能不影响到手机的性能? In mobile application
how much is the maxim Ripple ..? |
| [答：] |
The ripple must be measured on the base of the component
inside the PCB. Can not be defined as general parameeter. |
| [问：] |
74VCXH1632245 上升/下降沿时间值： |
| [答：] |
 |
中电网官方微博
