- 您现在的位置：买卖IC网 > PDF目录16905 > MIC2537-2BM (Micrel Inc)IC USB SWITCH QUAD 16-SOIC PDF资料下载
参数资料
| 型号： | MIC2537-2BM |
| 厂商： | Micrel Inc |
| 文件页数： | 8/12页 |
| 文件大小： | 0K |
| 描述： | IC USB SWITCH QUAD 16-SOIC |
| 标准包装： | 48 |
| 类型： | USB 开关 |
| 输出数： | 4 |
| Rds（开）： | 700 毫欧 |
| 内部开关： | 是 |
| 电流限制： | 250mA |
| 输入电压： | 3 V ~ 5.5 V |
| 工作温度： | -40°C ~ 85°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 16-SOIC（0.154"，3.90mm 宽） |
| 供应商设备封装： | 16-SOIC |
| 包装： | 管件 |
MIC2537
Functional Description
The MIC2537-1 and MIC2537-2 are quad high-side switches
with active-high and active-low enable inputs, respectively.
Fault conditions turn off or inhibit turn-on of one or more of the
output transistors, depending upon the type of fault, and
activate the open-drain error flag transistors making them
sink current to ground.
Input and Output
IN (input) is the power supply connection to the logic circuitry
and the drain of each output MOSFET. OUTx (output) is the
source of each respective MOSFET. In a typical circuit,
current flows through the switch from IN to OUTx toward the
load. If V OUT is greater than V IN , current will flow from OUT
to IN since the MOSFET is bidirectional when on.
The output MOSFET and driver circuitry are also designed to
allow the MOSFET source to be externally forced to a higher
voltage than the drain (V OUTx > V IN ) when the output is off. In
this situation, the MIC2537 prevents reverse current flow.
Thermal Shutdown
Thermal shutdown shuts off the affected output MOSFET
and signals the corresponding fault flags if the die tempera-
ture exceeds 135 ° C. 10 ° C of hysteresis prevents the switch
from turning on until the die temperature drops to 125 ° C.
Overtemperature detection functions only when at least one
switch is enabled.
Current-Limit Induced Thermal Shutdown
Internal circuitry increases the output MOSFET on-resis-
tance until the series combination of the MOSFET on-resis-
tance and the load impedance limits output current to ap-
proximately 200mA. The resulting increase in power dissipa-
tion may cause the shorted channel to go into thermal
shutdown. In addition, even though individual channels are
thermally isolated, it is possible they may shut down when an
adjacent channel is shorted. When this is undesirable, shut-
down of the channels not shorted can be avoided by exter-
nally responding to the fault and disabling the current limited
channel before the shutdown temperature is reached. The
delay between the flag indication of a current limit fault and
thermal shutdown will vary with ambient temperature, board
layout, and load impedance, but is typically several seconds.
The USB controller must therefore recognize a fault and
disable the appropriate channel within this time.
Micrel
Current Sensing and Limiting
The current-limit threshold is preset internally. The preset
level prevents damage to the output MOSFET and external
load but allows a minimum current of 0.15A through the
output MOSFET of each channel.
The current-limit circuit senses a portion of the output FET
switch current. The current sense resistor shown in the block
diagram is virtual and has no voltage drop. The reaction to an
overcurrent condition varies with the following three sce-
narios:
Switch Enabled into Short Circuit
If a switch is powered on or enabled into an excessive load or
short circuit, the switch immediately goes into a constant-
current mode, slowly increasing the output voltage. The fault
flag goes low until the load is reduced.
Short Circuit Applied to Output
When a heavy load or short circuit is applied to an enabled
switch, a large transient current may flow until the current-
limit circuitry responds. Once this occurs, the device limits
current to less than the short circuit current-limit specification.
See the “ Functional Characteristics: Current-Limit Transient
Response graph for details.
Current-Limit Response
The MIC2537 current-limit profile exhibits a small foldback
effect of approximately 100mA. Once this current-limit thresh-
old is exceeded the device enters constant-current mode.
This constant current is specified as the short-circuit current
limit in the “ Electrical Characteristics ” table. It is important to
note that the MIC2537 will deliver load current up to the
current-limit threshold. See the “ Functional Characteristics:
Current-Limit Response ” graph for details.
Fault Flag
FLGx is an open-drain N-channel MOSFET output. Fault
flags are active (low) for current limit or thermal shutdown.
Each flag output MOSFET is capable of sinking a 10mA load
to approximately 200mV above ground. Several FLGx pins
may be wired-NOR connected to a common pull-up resistor.
December 1999
8
MIC2537
相关PDF资料 |
PDF描述 |
|---|---|
| 5-1589777-1 | WDUALOBE CONNECTOR |
| ESC06DTEN | CONN EDGECARD 12POS .100 EYELET |
| 3186GY682M400MPC1 | CAP ALUM 6800UF 400V 20% SCREW |
| LNK2V103MSEJ | CAP ALUM 10000UF 350V 20% SCREW |
| ESC06DTEH | CONN EDGECARD 12POS .100 EYELET |
相关代理商/技术参数 |
参数描述 |
|---|---|
| MIC2537-2BM TR | 功能描述:IC USB SWITCH QUAD 16-SOIC RoHS:否 类别:集成电路 (IC) >> PMIC - 电源分配开关 系列:- 特色产品:XRP252 Switches 标准包装:1 系列:- 类型:高端开关 输出数:2 Rds（开）:140 毫欧 内部开关:是 电流限制:1.15A 输入电压:1.75 V ~ 5.5 V 工作温度:-40°C ~ 85°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（3x3） 包装:Digi-Reel® 其它名称:1016-1691-6 |
| MIC2537-2YM | 功能描述:电源开关 IC - USB Quad USB Switch (Lead Free) RoHS:否 制造商:Micrel 电源电压-最小:2.7 V 电源电压-最大:5.5 V 最大工作温度:+ 85 C 最小工作温度:- 40 C 封装 / 箱体:SOIC-8 封装:Tube |
| MIC2537-2YM TR | 功能描述:电源开关 IC - USB Quad USB Switch (Lead Free) RoHS:否 制造商:Micrel 电源电压-最小:2.7 V 电源电压-最大:5.5 V 最大工作温度:+ 85 C 最小工作温度:- 40 C 封装 / 箱体:SOIC-8 封装:Tube |
| MIC25383R-JBQS | 制造商:RF Micro Devices Inc 功能描述: |
| MIC25400YML TR | 功能描述:直流/直流开关调节器 2A Dual Output PWM Synchronous Buck Regulator RoHS:否 制造商:International Rectifier 最大输入电压:21 V 开关频率:1.5 MHz 输出电压:0.5 V to 0.86 V 输出电流:4 A 输出端数量: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:PQFN 4 x 5 |
发布紧急采购，3分钟左右您将得到回复。