- 您现在的位置：买卖IC网 > PDF目录19786 > MAX5903NNETT+T (Maxim Integrated)IC HOT-SWAP CONTROLLER 6-TDFN PDF资料下载
参数资料
| 型号： | MAX5903NNETT+T |
| 厂商： | Maxim Integrated |
| 文件页数： | 9/14页 |
| 文件大小： | 333K |
| 描述： | IC HOT-SWAP CONTROLLER 6-TDFN |
| 产品培训模块： | Lead (SnPb) Finish for COTS Obsolescence Mitigation Program |
| 标准包装： | 2,500 |
| 系列： | Simple Swapper™ |
| 类型： | 热交换控制器 |
| 应用： | 通用 |
| 内部开关： | 无 |
| 电源电压： | 9 V ~ 72 V |
| 工作温度： | -40°C ~ 85°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 6-WDFN 裸露焊盘 |
| 供应商设备封装： | 6-TDFN 裸露焊盘（3x3） |
| 包装： | 带卷 (TR) |
+72V, SOT23/TDFN, Simple Swapper Hot-Swap
Controllers
_______________________________________________________________________________________ 9
Selecting a Circuit-Breaker Threshold
The MAX5902A/MAX5903A and the MAX5902L/
MAX5903L offer a circuit-breaker function to protect the
external MOSFET and the load from the potentially
damaging effects of excessive current. As load current
flows through the external MOSFET, a voltage, V
SD
, is
generated from source to drain due to the MOSFETs
on-resistance, R
DS(ON)
. The MAX5902A/MAX5903A
and MAX5902L/MAX5903L monitor V
SD
when the exter-
nal MOSFET is fully enhanced. If V
SD
exceeds the
circuit-breaker threshold the external MOSFET is turned
off, and PGOOD (PGOOD) is deasserted. To accom-
modate different MOSFETs and different load currents
the MAX5902/MAX5903 are available with circuit-break-
er threshold voltages of 300mV, 400mV, and 500mV. To
determine the proper circuit-breaker threshold for an
application use:
V
CB
> (R
DS(ON)
) (I
OUT(MAX)
)
where R
DS(ON)
is the on-resistance of the MOSFET and
I
OUT
(MAX) is the maximum expected output current.
The MAX5902N/MAX5903N have no circuit-breaker
function. For these parts choose an external MOSFET
which meets the load requirements.
The circuit-breaker function is intended to protect
against gross overcurrent or short-circuit conditions.
During a gross overcurrent or short-circuit condition,
the MAX5902/MAX5903 disconnect the load by dis-
abling the external MOSFET. For calculating the circuit-
breaker threshold use the MOSFETs R
ON
at the worst
possible operating condition, and add a 20% overcur-
rent margin to the maximum circuit current. For
instance, if a MOSFET has an R
ON
of 0.06& at T
A
=
+25癈, and a normalized on-resistance factor of 1.75 at
T
A
= +130癈 (from the MOSFET data sheet), the R
ON
used for calculation is the product of these two num-
bers, or (0.06&) x (1.75) = 0.105&. Then, if the maxi-
mum current is expected to be 2A, using a 20%
margin, the current for calculation is (2A) x (1.2) = 2.4A.
The resulting minimum circuit-breaker threshold is then
a product of these two results, or (0.105&) x (2.4A) =
0.252V. The next highest minimum available threshold
is 0.280V of the MAX5902ABEUT, which is an ideal
choice given these parameters. Using this method to
choose a circuit-breaker threshold allows the circuit to
operate under worst case conditions without causing a
circuit-breaker fault, but the circuit-breaker function will
still operate if a short circuit, or a gross overcurrent
condition exists.
Determining Inrush Current
Determining a circuits inrush current is necessary to
help choose the proper MOSFET. The MAX5902/
MAX5903 regulate the inrush current by means of con-
trolling the load voltage slew rate, but inrush current is
also a function of load capacitance. Determine inrush
current using:
where C is the load capacitance, and SR is the
MAX5902/MAX5903 Load Voltage Slew-Rate
Magnitude from the Electrical Characteristics table. For
example, assuming a load capacitance of 100礔, and
using the typical value of 9V/ms for the slew rate, the
inrush current is 0.9A typical.
If the maximum possible Load Voltage Slew Rate is
used, the maximum inrush current calculates to 1.8A.
Choose a MOSFET with a maximum pulsed current
specification that exceeds the maximum inrush current.
I C
dV
dt
C SR
=
= ?/DIV>
GROUND
POWER IN
POWER
OUT
M1
SOT-223
S D G
U1
SOT23-6
MAX5902/MAX5903
Figure 7. Circuit Board Layout Example.
MAXIMUM
I
LOAD
(A)
SUGGESTED
EXTERNAL
MOSFET
SUGGESTED MAXIM
PART
0.5
IRF9540NS
MAX5902AAEUT
1
IRF9540NS
MAX5902ABEUT
2
IRF5210S
MAX5902ABEUT
3
IRF5210S
MAX5902ACEUT
V
IN
= +9V to +72V
相关PDF资料 |
PDF描述 |
|---|---|
| ABC28DRYI-S734 | CONN EDGECARD 56POS DIP .100 SLD |
| EEC05DRXN | CONN EDGECARD 10POS DIP .100 SLD |
| LCMXO1200E-5BN256C | IC FPGA 1.2KLUTS 256CABGA |
| RS3GB-13-F | DIODE FAST REC 400V 3A SMB |
| LCMXO1200C-4BN256I | IC FPGA 1.2KLUTS 256CABGA |
相关代理商/技术参数 |
参数描述 |
|---|---|
| MAX5903NNEUT | 制造商:Maxim Integrated Products 功能描述:SIMPLE SWAPPER HOT-SWAP SWITCHES - Rail/Tube |
| MAX5903NNEUT+ | 制造商:Maxim Integrated Products 功能描述:- Rail/Tube |
| MAX5903NNEUT+T | 功能描述:热插拔功率分布 72V Hot-Swap Controller 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 |
| MAX5903NNEUT-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 |
| MAX5904ESA | 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 |
发布紧急采购，3分钟左右您将得到回复。