If I
CB
is set to twice I
LOAD
, or 5A, V
DS
momentarily dou-
bles to d1.25V. If C
OUT
= 4000礔, transient-line input
voltage is 36V, and the 5A charging-current pulse is:
Entering the data sheet transient-thermal-resistance
curves at 1ms provides a ?/DIV>
JC
= 0.9癈/W. P
D
= 6.25W,
so t
JC
= 5.6癈. Clearly, this is not a problem.
Example 2:
I
LOAD
= 10A, efficiency = 98%, allowing V
DS
= 0.96V
but R
DS(ON)
d 96m&. An IRF530 in a D
2
PAK exhibits
R
DS(ON)
d 90m& at +25癈 and d 135m& at +80癈.
Power dissipation is 9.6W at +25癈 or 14.4W at +80癈.
Junction-to-case thermal resistance is 1.9W/癈, so the
junction-temperature rise would be approximately 5癈
above the +25癈 case temperature. For higher efficien-
cy, consider IRL540NS with R
DS(ON)
d 44m&. This
allows ?= 99%, P
D
d 4.4W, and T
JC
= +4癈 (?/DIV>
JC
=
1.1癈/W) at +25癈.
Thermal calculations for the transient condition yield
I
CB
= 20A, V
DS
= 1.8V, t = 0.5ms, transient ?/DIV>
JC
=
0.12癈/W, P
D
= 36W and t
JC
= 4.3癈.
t
F x
V
A
ms
   
.
   
=
=
4000
1 25
5
1
?/DIV>
-48V Hot-Swap Controllers
with External R
SENSE
16   ______________________________________________________________________________________
SENSE RESISTOR
HIGH-CURRENT PATH
MAX5949A
MAX5949B
SENSE V
EE
Figure 16. Recommended Layout for Kelvin-Sensing Current
Through Sense Resistor
Selector Guide
PART
PWRGD POLARITY
FAULT MANAGEMENT
MAX5949AESA
Active low (PWRGD)
Latched
MAX5949BESA
Active high (PWRGD)
Latched
相关PDF资料
MAX5950ETJ+ IC PWM CTRL HOT-SW 12V 32TQFN-EP
MAX5952CUAX+ IC PSE CNTRLR FOR POE 36-SSOP
MAX5953DUTM+ IC INTERFACE 802.3AF 48TQFN
MAX5954LETX+T IC PCI EXP/HOT-PLUG CTRLR 36TQFN
MAX5955BEEE+ IC DUAL HOT-SWAP CTRLR 16-QSOP
MAX5957AETN+T IC TRPL PCI EXP/HOT-PLUG 56-TQFN
MAX5960AECS+T IC CTRLR HOT-PLUG QD 80-TQFP
MAX5963UTL+T IC HOT SWAP DIO ORING CTL 40TQFN
相关代理商/技术参数
MAX5949BESA-T 功能描述:热插拔功率分布 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
MAX5950ETJ 功能描述:电压模式 PWM 控制器 RoHS:否 制造商:Texas Instruments 输出端数量:1 拓扑结构:Buck 输出电压:34 V 输出电流: 开关频率: 工作电源电压:4.5 V to 5.5 V 电源电流:600 uA 最大工作温度:+ 125 C 最小工作温度:- 40 C 封装 / 箱体:WSON-8 封装:Reel
MAX5950ETJ+ 功能描述:电压模式 PWM 控制器 12V PWM Controller w/Hot-Swap RoHS:否 制造商:Texas Instruments 输出端数量:1 拓扑结构:Buck 输出电压:34 V 输出电流: 开关频率: 工作电源电压:4.5 V to 5.5 V 电源电流:600 uA 最大工作温度:+ 125 C 最小工作温度:- 40 C 封装 / 箱体:WSON-8 封装:Reel
MAX5950ETJ+T 功能描述:电压模式 PWM 控制器 12V PWM Controller w/Hot-Swap RoHS:否 制造商:Texas Instruments 输出端数量:1 拓扑结构:Buck 输出电压:34 V 输出电流: 开关频率: 工作电源电压:4.5 V to 5.5 V 电源电流:600 uA 最大工作温度:+ 125 C 最小工作温度:- 40 C 封装 / 箱体:WSON-8 封装:Reel
MAX5950ETJ-T 功能描述:电压模式 PWM 控制器 RoHS:否 制造商:Texas Instruments 输出端数量:1 拓扑结构:Buck 输出电压:34 V 输出电流: 开关频率: 工作电源电压:4.5 V to 5.5 V 电源电流:600 uA 最大工作温度:+ 125 C 最小工作温度:- 40 C 封装 / 箱体:WSON-8 封装:Reel
MAX5950EVKIT 制造商:Maxim Integrated Products 功能描述:12V PWM CONTROLLER WITH HOT-SWAP - Rail/Tube
MAX5951ETJ 功能描述:电压模式 PWM 控制器 RoHS:否 制造商:Texas Instruments 输出端数量:1 拓扑结构:Buck 输出电压:34 V 输出电流: 开关频率: 工作电源电压:4.5 V to 5.5 V 电源电流:600 uA 最大工作温度:+ 125 C 最小工作温度:- 40 C 封装 / 箱体:WSON-8 封装:Reel
MAX5951ETJ+ 功能描述:电压模式 PWM 控制器 12V/5V Buck PWM Controller RoHS:否 制造商:Texas Instruments 输出端数量:1 拓扑结构:Buck 输出电压:34 V 输出电流: 开关频率: 工作电源电压:4.5 V to 5.5 V 电源电流:600 uA 最大工作温度:+ 125 C 最小工作温度:- 40 C 封装 / 箱体:WSON-8 封装:Reel