- 您现在的位置：买卖IC网 > PDF目录19796 > MIC2595R-2YM (Micrel Inc)IC CTRLR HOT SWAP NEG HV 14-SOIC PDF资料下载
参数资料
| 型号： | MIC2595R-2YM |
| 厂商： | Micrel Inc |
| 文件页数： | 23/29页 |
| 文件大小： | 4205K |
| 描述： | IC CTRLR HOT SWAP NEG HV 14-SOIC |
| 标准包装： | 54 |
| 类型： | 热交换控制器 |
| 应用： | 通用 |
| 内部开关： | 无 |
| 电源电压： | -19 V ~ -80 V |
| 工作温度： | -40°C ~ 85°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 14-SOIC（0.154"，3.90mm 宽） |
| 供应商设备封装： | 14-SOIC |
| 包装： | 管件 |
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页第21页第22页当前第23页第24页第25页第26页第27页第28页第29页
Micrel
MIC2589/MIC2595
December 2005
23
M9999-120505
(408) 955-1690
higher pulsed power without damage than its
continuous power dissipation ratings imply due to an
inherent trait, thermal inertia. With respect to the
specification and use of power MOSFETs, the
parameter of interest is the Transient Thermal
Impedance , or Z
?/DIV>
, which is a real number (variable
factor) used as a multiplier of the thermal resistance
(R
?/DIV>
). The multiplier is determined using the given
Transient Thermal Impedance Graph , normalized to
R
?/DIV>
, that displays curves for the thermal impedance
versus power pulse duration and duty cycle. The
single-pulse curve is appropriate for most hot swap
applications. Z
?/DIV>
is specified from junction-to-case for
power MOSFETs typically used in telecom
applications.
The following example provides a method for
estimating the peak junction temperature of a power
MOSFET in determining if the MOSFET is suitable for
a
particular
application.
V
IN
(VDD VEE) = 48V, I
LIM
= 4.2A, t
FLT
is 20ms, and
the power MOSFET is the SUM110N10-09 (TO-263
package) from Vishay-Siliconix. This MOSFET has an
R
ON
of 9.5m& (T
J
= 25癈), the junction-to-case
thermal resistance (R
?J-C)
) is 0.4癈/W, junction-to-
ambient thermal resistance (R
?J-A)
) is 40癈/W, and the
Transient Thermal Impedance Curve is shown in
Figure 8. Consider, say, the MOSFET is switched on
at time t1 and the steady-state load current passing
through the MOSFET is 3A. At some point in time
after t1, at time t2, there is an unexpected short-circuit
applied to the load, causing the MIC2589/MIC2595
controller to adjust the GATE output voltage and
regulate the load current for 20ms at the programmed
current limit value, 4.2A in this example. During this
short-circuit load condition, the dissipation in the
MOSFET is calculated by:
P
D
(short) = V
DS
?I
LIM
; V
DS
= 0V (-48V) = 48V
P
D
(short) = 48V ?4.2A = 201.6W for 20ms.
At first glance, it would appear that a very hefty
MOSFET is required to withstand this extreme
overload condition. Upon further examination, the
calculation to approximate the peak junction
temperature is not a difficult task. The first step is to
determine the maximum steady-state junction
temperature, then add the rise in temperature due to
the maximum power dissipated during a transient
overload caused by a short circuit condition. The
equation to estimate the maximum steady-state
junction temperature is given by:
T
J
(steady-state) E T
C
(max) + T
J
(1)
T
C
(max) is the highest anticipated case temperature,
prior to an overcurrent condition, at which the
MOSFET will operate and is estimated from the
following equation based on the highest ambient
temperature of the system environment.
T
C
(max) = T
A
(max) + P
D
?(R
?J-A)
R
?J-C)
)
(2)
Lets assume a maximum ambient of 60癈. The
power dissipation of the MOSFET is determined by
the current through the MOSFET and the ON
resistance (I
2
R
ON
), which we will estimate at 17m&
(specification given at T
J
= 125癈). Using our
example information and substituting into Equation 2,
T
C
(max) = 60癈+[((3A)
2
?7m&)?400.4)癈/W]
= 66.06癈
Substituting the variables into Equation 1, T
J
is
determined by:
T
J
(steady-state) ET
C
(max)+[R
O N
+(T
C
(max)T
C
)(0.005)
?(R
O N
)][I
2
?R
?(J -A )
R
?( J- C)
)]
E 66.06癈+[17m&+(66.06癈25癈)(0.005/癈)
?17m&)][(3A)
2
?400.4)癈/W]
E 66.06癈 + 7.30癈
E 73.36癈
Since this is not a closed-form equation, getting a
close approximation may take one or two iterations.
On the second iteration, start with T
J
equal to the
value calculated above. Doing so in this example
yields;
T
J
(steady-state) E66.06癈+[17m&+(73.36癈
-25癈)?0.005/癈)
?17m&)][(3A)
2
?400.4)]癈/W
E73.62癈
Another iteration shows that the result (73.63癈) is
converging quickly, so well estimate the maximum
T
J(steady-state)
at 74癈.
The use of the Transient Thermal Impedance Curves
is necessary to determine the increase in junction
temperature associated with a worst-case transient
condition. From our previous calculation of the
maximum power dissipated during a short circuit
event for the MIC2589/MIC2595, we calculate the
transient junction temperature increase as:
T
J
(transient) = P
D
(short) ?R
?J-C)
?Multiplier
(3)
Assume the MOSFET has been on for a long time
several minutes or more and delivering the steady-
state load current of 3A to the load when the load is
short circuited. The controller will regulate the GATE
output voltage to limit the current to the programmed
value of 4.2A for 20ms before immediately shutting off
the output. For this situation and almost all hot swap
applications, this can be considered a single pulse
event as there is no significant duty cycle. From
Figure 8, find the point on the X-axis ( Square-Wave
Pulse Duration ) for 25ms, allowing for a 25% margin
相关PDF资料 |
PDF描述 |
|---|---|
| MIC5200-5.0BS | IC REG LDO 5V .1A SOT223 |
| MAX8527EUD/V+ | IC REG LDO ADJ 2A 14TSSOP |
| EEM25DSEI | CONN EDGECARD 50POS .156 EYELET |
| MIC5200-5.0BM | IC REG LDO 5V .1A 8SOIC |
| GEM18DTMD-S189 | CONN EDGECARD 36POS R/A .156 SLD |
相关代理商/技术参数 |
参数描述 |
|---|---|
| MIC2595R-2YM TR | 功能描述:热插拔功率分布 Negative Voltage Hot-Swap Controller - Lead Free RoHS:否 制造商:Texas Instruments 产品:Controllers & Switches 电流限制: 电源电压-最大:7 V 电源电压-最小:- 0.3 V 工作温度范围: 功率耗散: 安装风格:SMD/SMT 封装 / 箱体:MSOP-8 封装:Tube |
| MIC2595R-2YM-TR | 功能描述:Hot Swap Controller, Sequencer 1 Channel -48V 14-SOIC 制造商:microchip technology 系列:- 包装:剪切带（CT） 零件状态:停产 类型:热交换控制器，序列发生器 通道数:1 内部开关:无 应用:-48V 特性:自动重试 可编程特性:限流，故障超时，UVLO 电压 - 电源:-80 V ~ -19 V 电流 - 输出（最大值）:- 工作温度:-40°C ~ 85°C 电流 - 电源:4mA 安装类型:表面贴装 封装/外壳:14-SOIC（0.154"，3.90mm 宽） 供应商器件封装:14-SOIC 功能引脚:CFILTER，CNLD，DRAIN，PGTIMER，OFF，ON，/PWRGD1，/PWRGD2，/PWRGD3 标准包装:1 |
| MIC2596-1BTS | 功能描述:IC SWITCH HOT SWAP DUAL 20-TSSOP RoHS:否 类别:集成电路 (IC) >> PMIC - 热交换 系列:- 产品培训模块:Obsolescence Mitigation Program 标准包装:100 系列:- 类型:热插拔开关 应用:通用 内部开关:是 电流限制:可调 电源电压:9 V ~ 13.2 V 工作温度:-40°C ~ 150°C 安装类型:表面贴装 封装/外壳:10-WFDFN 裸露焊盘 供应商设备封装:10-TDFN-EP（3x3） 包装:管件 |
| MIC2596-1BTS TR | 功能描述:IC SWITCH HOT SWAP DUAL 20-TSSOP RoHS:否 类别:集成电路 (IC) >> PMIC - 热交换 系列:- 产品培训模块:Obsolescence Mitigation Program 标准包装:100 系列:- 类型:热插拔开关 应用:通用 内部开关:是 电流限制:可调 电源电压:9 V ~ 13.2 V 工作温度:-40°C ~ 150°C 安装类型:表面贴装 封装/外壳:10-WFDFN 裸露焊盘 供应商设备封装:10-TDFN-EP（3x3） 包装:管件 |
| MIC2596-1BTSE | 功能描述:IC SWITCH HOT SWAP DUAL 20-TSSOP RoHS:否 类别:集成电路 (IC) >> PMIC - 热交换 系列:- 产品培训模块:Obsolescence Mitigation Program 标准包装:100 系列:- 类型:热插拔开关 应用:通用 内部开关:是 电流限制:可调 电源电压:9 V ~ 13.2 V 工作温度:-40°C ~ 150°C 安装类型:表面贴装 封装/外壳:10-WFDFN 裸露焊盘 供应商设备封装:10-TDFN-EP（3x3） 包装:管件 |
发布紧急采购，3分钟左右您将得到回复。