參數(shù)資料
型號: MIC2086-MBQS TR
廠商: Micrel Inc
文件頁數(shù): 24/29頁
文件大?。?/td> 1008K
描述: IC CTRLR HOW SWAP SGL 20-QSOP
標(biāo)準(zhǔn)包裝: 2,500
類型: 熱交換控制器
應(yīng)用: 通用型 Infiniband?
內(nèi)部開關(guān):
電源電壓: 2.3 V ~ 16.5 V
工作溫度: -40°C ~ 85°C
安裝類型: 表面貼裝
封裝/外殼: 20-SSOP(0.154",3.90mm 寬)
供應(yīng)商設(shè)備封裝: 20-QSOP
包裝: 帶卷 (TR)
其它名稱: MIC2086-MBQSTR
MIC2086-MBQSTR-ND
Micrel, Inc.
MIC2085/2086
 
 
May 2006 
24
M9999-050406
(408) 955-1690
 
 
Figure 11. Zener Clamped MOSFET GATE
 
2. Airflow works. Even a few LFM (linear feet per
minute) of air will cool a MOSFET down
substantially.    If    you    can,    position    the
MOSFET(s) near the inlet of a power supplys
fan, or the outlet of a processors cooling fan.
3. The best test of a surface-mount MOSFET for
an application (assuming the above tips show it
to be a likely fit) is an empirical one. Check the
MOSFET's temperature in the actual layout of
the expected final circuit, at full operating
current. The use of a thermocouple on the drain
leads, or infrared pyrometer on the package, will
then give a reasonable idea of the devices
junction temperature.
MOSFET Transient Thermal Issues
Having chosen a MOSFET that will withstand the
imposed   voltage   stresses,   and   the   worse   case
continuous I2R power dissipation which it will see, it
remains only to verify the MOSFETs ability to handle
short-term    overload    power    dissipation    without
overheating. A MOSFET can handle a much higher
pulsed power without damage than its continuous
dissipation ratings would imply. The reason for this is
that, like everything else, thermal devices (silicon die,
lead frames, etc.) have thermal inertia.
In terms related directly to the specification and use of
power MOSFETs, this is known as transient thermal
impedance, or Z
?J-A)
. Almost all power MOSFET data
sheets give a Transient Thermal Impedance Curve. For
example, take the following case: VIN = 12V, t
OCSLOW
 
has been set to 100msec, I
LOAD(CONT. MAX)
  is 2.5A, the
slow-trip threshold is 48mVnominal, and the fast-trip
threshold   is   95mV.   If   the   output   is   accidentally
connected to a 3& load, the output current from the
MOSFET will be regulated to 2.5A for 100ms (t
OCSLOW
)
before the part trips. During that time, the dissipation in
the MOSFET is given by:
 
P = E x I E
MOSFET
 = [12V-(2.5A)(3&)]=4.5V
  PMOSFET = (4.5V x 2.5A) = 11.25W for 100msec.
At first glance, it would appear that a really hefty
MOSFET is required to withstand this sort of fault
condition. This is where the transient thermal impedance
curves become very useful. Figure 12 shows the curve
for the Vishay (Siliconix) Si4410DY, a commonly used
SO-8 power MOSFET.
Taking the simplest case first, well assume that once a
fault event such as the one in question occurs, it will be
a long time  10 minutes or more  before the fault is
isolated and the channel is reset. In such a case, we can
approximate this as a single pulse event, that is to say,
theres no significant duty cycle. Then, reading up from
the X-axis at the point where Square Wave Pulse
Duration is equal to 0.1sec (=100msec), we see that the
Z
?J-A)
 of this MOSFET to a highly infrequent event of this
duration is only 8% of its continuous R
?J-A)
.
This particular part is specified as having an R
?J-A)
  of
50癈/W for intervals of 10 seconds or less. Thus:
Assume T
A
 = 55癈 maximum, 1 square inch of copper at
the drain leads, no airflow.
Recalling from our previous approximation hint, the part
相關(guān)PDF資料
PDF描述
MIC2225-4OYMT TR IC REG DL BUCK/LINEAR 10TMLF
MIC2310-2ZTS TR IC HOT SWAP CTLR 2CHAN 24TSSOP
MIC2341-2YTQ IC HOT PLUG CTLR DUAL PCI 48TQFP
MIC2569YQS TR IC POWER SWITCH CABLECARD 16QSOP
MIC2583R-MBQS TR IC CTRLR HOT SWAP 200MV 16-QSOP
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
MIC2086-XBQS 制造商:MICREL 制造商全稱:Micrel Semiconductor 功能描述:Single Channel Hot Swap Controllers
MIC2090 制造商:MICREL 制造商全稱:Micrel Semiconductor 功能描述:Current Limiting Power Distribution Switches
MIC2090_11 制造商:MICREL 制造商全稱:Micrel Semiconductor 功能描述:Current Limiting Power Distribution Switches
MIC2090-1YM5 制造商:MICREL 制造商全稱:Micrel Semiconductor 功能描述:Current Limiting Power Distribution Switches
MIC2090-1YM5 TR 功能描述:電源開關(guān) IC - USB 50mA Current Limiting Power Distribution Switch RoHS:否 制造商:Micrel 電源電壓-最小:2.7 V 電源電壓-最大:5.5 V 最大工作溫度:+ 85 C 最小工作溫度:- 40 C 封裝 / 箱體:SOIC-8 封裝:Tube