- 您现在的位置：买卖IC网 > PDF目录20058 > MAX5955AUEE+ (Maxim Integrated)IC DUAL HOT-SWAP CTRLR 16-QSOP PDF资料下载
参数资料
| 型号： | MAX5955AUEE+ |
| 厂商： | Maxim Integrated |
| 文件页数： | 12/15页 |
| 文件大小： | 354K |
| 描述： | IC DUAL HOT-SWAP CTRLR 16-QSOP |
| 产品培训模块： | Lead (SnPb) Finish for COTS Obsolescence Mitigation Program |
| 标准包装： | 100 |
| 类型： | 热交换控制器 |
| 应用： | 通用 |
| 内部开关： | 无 |
| 电源电压： | 1 V ~ 13.2 V |
| 工作温度： | 0°C ~ 85°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 16-SSOP（0.154"，3.90mm 宽） |
| 供应商设备封装： | 16-QSOP |
| 包装： | 管件 |
C
BOARD
= 6礔 and the load does not draw any current
during the startup period. With no gate capacitor the
inrush current, charge, and discharge times are:
With a 22nF gate capacitor the inrush current, charge,
and discharge times are:
Case B: Fast Turn-On (with Current Limit)
In applications where the board capacitance (C
BOARD
)
is high, the inrush current causes a voltage drop across
R
SENSE
that exceeds the startup fast-comparator
threshold. The fast comparator regulates the voltage
across the sense resistor to V
SU,TH
. This effectively
regulates the inrush current during startup. In this case,
the current charging C
BOARD
can be considered con-
stant and the turn-on time is:
The maximum inrush current in this case is:
Figure 2 shows the waveforms and timing diagrams for a
startup transient with current regulation (see Typical
Operating Characteristics). When operating under this
condition, an external gate capacitor is not required.
ON_ Comparators
The ON_ comparators control the on/off function of the
MAX5955/MAX5956. ON_ allows independent control
over channel 1 and channel 2. Drive ON1 and ON2
high (> 0.875V) to enable channel 1 and channel 2,
respectively. Pull ON_ low (< 0.875V) to disable the
respective channel. An RC time delay must be added
to the ON_ inputs with delay set to at least 20祍. This
allows the internal circuits to stabilize after application
of a steeply rising V
IN_
.
Using the MAX5955/MAX5956 on the
Backplane
Using the MAX5955/MAX5956 on the backplane allows
multiple cards with different input capacitance to be
inserted into the same slot even if the card does not
have on-board hot-swap protection. The startup period
can be triggered if IN_ is connected to ON_ through a
trace on the card (Figure 5).
Input Transients
The voltage at IN1 or IN2 must be above the UVLO dur-
ing inrush and fault conditions. When a short-circuit con-
dition occurs on the board, the fast comparator trips
causing the external MOSFET gates to be discharged at
3mA. The main system power supply must be able to
sustain a temporary fault current, without dropping below
the UVLO threshold of 2.4V, until the external MOSFET is
completely off. If the main system power supply collapses
below UVLO, the MAX5955/MAX5956 force the device to
restart once the supply has recovered. The MOSFET is
turned off in a very short time resulting in a high di/dt. The
backplane delivering the power to the external card must
have low inductance to minimize voltage transients
caused by this high di/dt.
MOSFET Thermal Considerations
During normal operation, the external MOSFETs dissi-
pate little power. The MOSFET R
DS(ON)
is low when the
MOSFET is fully enhanced. The power dissipated in
normal operation is P
D
= I
LOAD
2
x R
DS(ON)
. The most
power dissipation occurs during the turn-on and turn-
off transients when the MOSFETs are in their linear
regions. Take into consideration the worst-case sce-
nario of a continuous short-circuit fault, consider these
two cases:
1) The single turn-on with the device latched after a
fault (MAX5955B/MAX5956B)
2) The continuous automatic retry after a fault
(MAX5955A/MAX5956A)
MOSFET manufacturers typically include the package
thermal resistance from junction to ambient (R
窲A
) and
thermal resistance from junction to case (R
窲C
), which
determine the startup time and the retry duty cycle
(d = t
START
/t
START
+ t
RETRY
). Calculate the required
transient thermal resistance with the following equation:
where I
START
= V
SU,TH
/ R
SENSE
Z
T
T
V I
JA MAX
JMAX
A
IN START
?nbsp (
)
d
?/DIV>
I
V
R
INRUSH
SUTH
SENSE
=
,
t
C
V R
V
ON
BOARD
IN
SENSE
SUTH
=
?nbsp ?/DIV>
,
I
F
pF
nF
A
mA
t
nF
V
nC
A
ms
t
nF
V
nC
mA
ms
INRUSH
CHARGE
DISCHARGE
=
?/DIV>
+
?nbsp ?nbsp + =
=
?/DIV>
+
?/DIV>
=
=
?/DIV>
+
=
6
600
22
100
0 26 5
22
10 4 60
100
2 89
22
10 4 60
3
0 096
.
.
.
.
.
I
F
pF
A
A
t
V
nC
A
ms
t
V
nC
mA
ms
INRUSH
CHARGE
DISCHARGE
=
?/DIV>
+
?nbsp ?nbsp + =
=
?/DIV>
+
?/DIV>
=
=
?/DIV>
+
=
6
600
0
100
0 1
0 10 4 60
100
0 6
0 10 4 60
3
0 02
.
.
.
.
Low-Voltage, Dual Hot-Swap Controllers with
Independent On/Off Control
12 ______________________________________________________________________________________
相关PDF资料 |
PDF描述 |
|---|---|
| 5747250-4 | CONN DSUB PLUG 9POS R/A GOLD |
| VE-2TR-CX | CONVERTER MOD DC/DC 7.5V 75W |
| MAX5923EUP+ | IC HOT-SWAP SWITCH +60V 20-TSSOP |
| ISL9000IRMGZ | IC REG LDO 3V/2.7V .3A 10-DFN |
| VI-2N3-CX-F1 | CONVERTER MOD DC/DC 24V 75W |
相关代理商/技术参数 |
参数描述 |
|---|---|
| MAX5955AUEE+ | 功能描述:热插拔功率分布 Dual 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 |
| MAX5955AUEE+T | 功能描述:热插拔功率分布 Dual 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 |
| MAX5955AUEE-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 |
| MAX5955BEEE | 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 |
| MAX5955BEEE+ | 功能描述:热插拔功率分布 Dual 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 |
发布紧急采购，3分钟左右您将得到回复。