參數(shù)資料
型號(hào)： LTC4227CGN-1#PBF
廠商： LINEAR TECHNOLOGY CORP
元件分類： 電源管理
英文描述： POWER SUPPLY MANAGEMENT CKT, PDSO16
封裝： 0.150 INCH, LEAD FREE, PLASTIC, SSOP-16
文件頁(yè)數(shù)： 7/20頁(yè)
文件大小： 307K
代理商： LTC4227CGN-1#PBF
LTC4227-1/LTC4227-2
15
422712f
applicaTions inForMaTion
greater than 10V. The gate drive is limited to not more than
14V. This allows the use of logic-level threshold N-channel
MOSFETs and standard N-channel MOSFETs above 7V. An
external Zener diode can be used to clamp the potential
from the MOSFET’s gate to source if the rated breakdown
voltage is less than 14V.
The maximum allowable drain-source voltage, BVDSS,
must be higher than the supply voltages as the full sup-
ply voltage can appear across the MOSFET. If an input or
output is connected to ground, the full supply voltage will
appear across the MOSFET. The RDS(ON) should be small
enough to conduct the maximum load current, and also
stay within the MOSFET’s power rating.
CPO Capacitor Selection
Therecommendedvalueofthecapacitor,CCP,betweenthe
CPO and IN pins is approximately 10
× the input capaci-
tance, CISS, of the ideal diode MOSFET. A larger capacitor
takes a correspondingly longer time to charge up by the
internal charge pump. A smaller capacitor suffers more
voltage drop during a fast gate turn-on event as it shares
charge with the MOSFET gate capacitance.
Supply Transient Protection
When the capacitances at the input and output are very
small, rapid changes in current during an input or output
short-circuit event can cause transients that exceed the
24V absolute maximum ratings of the IN and OUT pins.
To minimize such spikes, use wider traces or heavier
trace plating to reduce the power trace inductance. Also,
bypass locally with a 10F electrolytic and 0.1F ceramic,
or alternatively clamp the input with a transient voltage
suppressor (Z1, Z2). A 10Ω, 0.1F snubber damps the
response and eliminates ringing (See Figure 9).
Design Example
As a design example for selecting components, consider
a 12V system with a 7.6A maximum load current for the
two supplies (see Figure 1).
First, select the appropriate value of the current sense re-
sistor, RS, for the 12V supply. Calculate the sense resistor
value based on the maximum load current and the lower
limit for the circuit breaker threshold,
VSENSE(CB)(MIN):
RS =
VSENSE(CB)(MIN)
ILOAD(MAX)
=
47.5mV
7.6A
= 6.25m
Choose a 6mΩ sense resitor with a 1% tolerance. The
minimum and maximum circuit breaker trip current is
calculated as follows:
ITRIP(MIN) =
VSENSE(CB)(MIN)
RS(MAX)
=
47.5mV
6.06m
= 7.8A
ITRIP(MAX) =
VSENSE(CB)(MAX)
RS(MIN)
=
52.5mV
5.94m
= 8.8A
Forproperoperation,ITRIP(MIN)mustexceedthemaximum
load current with margin, so RS = 6mΩ should suffice for
the 12V supply.
Next, calculate the RDS(ON) of the ideal diode MOSFET to
achievethedesiredforwarddropatmaximumload.Assum-
ing a forward drop,
VFWD of 60mV across the MOSFET:
RDS(ON) ≤
VFWD
ILOAD(MAX)
=
60mV
7.6A
= 7.9m
The SiR462DP offers a good choice with a maximum
RDS(ON) of 7.9mΩ at VGS = 10V. The input capacitance,
CISS, of the SiR462DP is about 1155pF. Slightly exceeding
the 10
× recommendation, a 0.1F capacitor is selected
for CCP1 and CCP2 at the CPO pins.
Next, verify that the thermal ratings of the selected Hot
SwapMOSFET,Si7336ADP,arenotexceededduringpower-
up or an output short.
Assuming the MOSFET dissipates power due to inrush
current charging the load capacitor, CL, at power-up, the
energy dissipated in the MOSFET is the same as the energy
stored in the load capacitor, and is given by:
ECL =
1
2
CL VIN2
相關(guān)PDF資料
PDF描述
LTC4251IS6 1-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO6
LTC4251CS6 1-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO6
LTC4259CGW#PBF 4-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO36
LTC4259CGW 4-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO36
LTC4267CGN-1#TR 1 A SWITCHING CONTROLLER, 240 kHz SWITCHING FREQ-MAX, PDSO16
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
LTC4227CGN-2#PBF 功能描述:IC CTLR HOT SWAP DUAL 16-SSOP RoHS:是 類別:集成電路 (IC) >> PMIC - 熱交換 系列:- 標(biāo)準(zhǔn)包裝:50 系列:- 類型:熱交換控制器 應(yīng)用:-48V 遠(yuǎn)程電力系統(tǒng)，AdvancedTCA ? 系統(tǒng)，高可用性 內(nèi)部開關(guān):無(wú) 電流限制:可調(diào) 電源電壓:11.5 V ~ 14.5 V 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:10-TFSOP，10-MSOP（0.118"，3.00mm 寬） 供應(yīng)商設(shè)備封裝:10-MSOP 包裝:管件
LTC4227CGN-2#TRPBF 功能描述:IC CTRLR HOT SWAP 16-SSOP RoHS:是 類別:集成電路 (IC) >> PMIC - 熱交換 系列:- 產(chǎn)品培訓(xùn)模塊:Obsolescence Mitigation Program 標(biāo)準(zhǔn)包裝:100 系列:- 類型:熱插拔開關(guān) 應(yīng)用:通用 內(nèi)部開關(guān):是 電流限制:可調(diào) 電源電壓:9 V ~ 13.2 V 工作溫度:-40°C ~ 150°C 安裝類型:表面貼裝 封裝/外殼:10-WFDFN 裸露焊盤 供應(yīng)商設(shè)備封裝:10-TDFN-EP（3x3） 包裝:管件
LTC4227CUFD-1#PBF 功能描述:IC CTRLR HOT SWAP 20-QFN RoHS:是 類別:集成電路 (IC) >> PMIC - 熱交換 系列:- 產(chǎn)品培訓(xùn)模塊:Obsolescence Mitigation Program 標(biāo)準(zhǔn)包裝:100 系列:- 類型:熱插拔開關(guān) 應(yīng)用:通用 內(nèi)部開關(guān):是 電流限制:可調(diào) 電源電壓:9 V ~ 13.2 V 工作溫度:-40°C ~ 150°C 安裝類型:表面貼裝 封裝/外殼:10-WFDFN 裸露焊盤 供應(yīng)商設(shè)備封裝:10-TDFN-EP（3x3） 包裝:管件
LTC4227CUFD-1#TRPBF 功能描述:IC CTRLR HOT SWAP 20-QFN RoHS:是 類別:集成電路 (IC) >> PMIC - 熱交換 系列:- 產(chǎn)品培訓(xùn)模塊:Obsolescence Mitigation Program 標(biāo)準(zhǔn)包裝:100 系列:- 類型:熱插拔開關(guān) 應(yīng)用:通用 內(nèi)部開關(guān):是 電流限制:可調(diào) 電源電壓:9 V ~ 13.2 V 工作溫度:-40°C ~ 150°C 安裝類型:表面貼裝 封裝/外殼:10-WFDFN 裸露焊盤 供應(yīng)商設(shè)備封裝:10-TDFN-EP（3x3） 包裝:管件
LTC4227CUFD-2#PBF 功能描述:IC CTRLR HOT SWAP 20-QFN RoHS:是 類別:集成電路 (IC) >> PMIC - 熱交換 系列:- 產(chǎn)品培訓(xùn)模塊:Obsolescence Mitigation Program 標(biāo)準(zhǔn)包裝:100 系列:- 類型:熱插拔開關(guān) 應(yīng)用:通用 內(nèi)部開關(guān):是 電流限制:可調(diào) 電源電壓:9 V ~ 13.2 V 工作溫度:-40°C ~ 150°C 安裝類型:表面貼裝 封裝/外殼:10-WFDFN 裸露焊盤 供應(yīng)商設(shè)備封裝:10-TDFN-EP（3x3） 包裝:管件
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

*
*
*