參數(shù)資料
型號(hào)： TPS2376DDA-H
廠商： TEXAS INSTRUMENTS INC
元件分類： 電源管理
英文描述： 1-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO8
封裝： GREEN, PLASTIC, POWER PAD, SOIC-8
文件頁(yè)數(shù)： 5/23頁(yè)
文件大?。?/td> 640K
代理商： TPS2376DDA-H
www.ti.com
TPS237X
SMAJ58A
R(DET)
R(CLASS)
VDD
VSS
CLASS
DET
RTN
Main
DC/DC
Converter
Output
R(ILIM)
RJ45
Option 1
ILIM
DC/DC
Converter
UCC3809
or
UCC3813
Optional
Regulator
Option 2
Option 3
A Full Wave Bridge
Gives Flexibility To
Use Supply With Either
Polarity
For Option 2,
The Capacitor Must Be
Right At The Output
To Control The
Transients.
Auxiliary
Power
Input
Use only
one option
See TI Document SLVR030 For A Typical
Application Circuit.
~
+
~
+
0.1
F
22
F
Inserting a Diode in This Location
With Option 2, Allows PoE To Start
With Aux Power Present.
SLVS646A – SEPTEMBER 2006 – REVISED SEPTEMBER 2006
APPLICATION INFORMATION (continued)
Figure 14. Auxiliary Power ORing
Option 1 consists of ORing power to the output of the PoE dc/dc converter. This option is preferred in cases
where PoE is added to an existing design that uses a low-voltage wall adapter. The relatively large PD
capacitance reduces the potential for harmful transients when the adapter is plugged in. The wall adapter output
may be grounded if the PD incorporates an isolated converter. This solution requires two separate regulators,
but low-voltage adapters are readily available. The PoE power can be given priority by setting its output voltage
above the adapter's.
Option 2 has the benefits that the adapter voltage may be lower than the TPS2376-H UVLO, and that the bulk
capacitor shown controls voltage transients caused by plugging an adapter in. The capacitor size and location
are chosen to control the amount of ringing that can occur on this node, which can be affected by additional
filtering components specific to a dc/dc converter design. The optional diode blocks the adapter voltage from
reverse biasing the input, and allows a PoE source to supply power provided that the PSE output voltage is
greater than the adapter voltage. The penalty of the diode is an additional power loss when running from PSE
power. The PSE may not be able to detect and start powering without the diode. This means that the adapter
may continue to power the PD until removed. Auxiliary voltage sources can be selected to be above or below
the PoE operational voltage range. If automatic PoE precedence is desired when using the low-voltage auxiliary
source option, make sure that the TPS2376-H inrush program limit is set higher than the maximum converter
input current at its lowest operating voltage. It is difficult to use PG with the low-voltage auxiliary source because
the converter must operate during a condition when the TPS2376-H would normally disable it. Circuits may be
designed to force operation from one source or the other depending on the desired operation and the auxiliary
source voltage chosen. However, they are not recommended because they increase complexity and thus cost.
Option 3 inserts the power before the TPS2376-H. The adapter output voltage must meet the TPS2376-H UVLO
turn-on requirement and limit the maximum voltage to 57 V. This option provides a valid power-good signal and
simplifies power priority issues. Option 3 is the most likely to create transient voltage problems when a powered
adapter is plugged in. This causes the cabling inductance and PD input capacitance to ring to a high voltage that
must be clamped by the TVS. If the adapter applies voltage to the PD before the PSE, it prevents the PSE from
detecting the PD. If the PSE is already powering the PD when the adapter is plugged in, priority is given to the
higher supply voltage.
13
相關(guān)PDF資料
PDF描述
TPS2390DGKR 1-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO8
TPS2390DGKRG4 1-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO8
TPS2391DGKRG4 1-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO8
TPS2390DGK 1-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO8
TPS2393APWRG4 1-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO14
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
TPS2376DDA-HG4 功能描述:熱插拔功率分布 IEEE 802.3af PoE High Power PD Cont RoHS:否 制造商:Texas Instruments 產(chǎn)品:Controllers & Switches 電流限制: 電源電壓-最大:7 V 電源電壓-最小:- 0.3 V 工作溫度范圍: 功率耗散: 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:MSOP-8 封裝:Tube
TPS2376DDAR-H 功能描述:熱插拔功率分布 IEEE 802.3af PoE Hi Pwr PD CONTROLLER RoHS:否 制造商:Texas Instruments 產(chǎn)品:Controllers & Switches 電流限制: 電源電壓-最大:7 V 電源電壓-最小:- 0.3 V 工作溫度范圍: 功率耗散: 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:MSOP-8 封裝:Tube
TPS2376DDAR-HG4 功能描述:熱插拔功率分布 IEEE 802.3af PoE Hi Pwr PD CONTROLLER RoHS:否 制造商:Texas Instruments 產(chǎn)品:Controllers & Switches 電流限制: 電源電壓-最大:7 V 電源電壓-最小:- 0.3 V 工作溫度范圍: 功率耗散: 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:MSOP-8 封裝:Tube
TPS2376DG4 功能描述:熱插拔功率分布 IEEE 802.3af PoE Pwr Device Cntrler RoHS:否 制造商:Texas Instruments 產(chǎn)品:Controllers & Switches 電流限制: 電源電壓-最大:7 V 電源電壓-最小:- 0.3 V 工作溫度范圍: 功率耗散: 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:MSOP-8 封裝:Tube
TPS2376DR 功能描述:熱插拔功率分布 IEEE 802.3af PoE Pwr Device Cntrler RoHS:否 制造商:Texas Instruments 產(chǎn)品:Controllers & Switches 電流限制: 電源電壓-最大:7 V 電源電壓-最小:- 0.3 V 工作溫度范圍: 功率耗散: 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:MSOP-8 封裝:Tube
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。

采購(gòu)需求

(若只采購(gòu)一條型號(hào)，填寫一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

*型號(hào) *數(shù)量 廠商 批號(hào) 封裝
添加更多采購(gòu)

我的聯(lián)系方式

*
*
*