参数资料
型号: LT4356HDE-1#TRPBF
厂商: Linear Technology
文件页数: 11/26页
文件大小: 0K
描述: IC OVERVOLT PROT REG 12-DFN
产品培训模块: LT4356 Surge Stopper
产品目录绘图: LT4356 Output Graph
LT4356 Series 12-DFN
标准包装: 2,500
电压 - 工作: 4 ~ 80V
电压 - 箝位: 27V,可调
技术: 混合技术
电路数: 1
应用: 自动
封装/外壳: 12-WFDFN 裸露焊盘
供应商设备封装: 12-DFN(4x3)
包装: 带卷 (TR)
配用: DC1018B-C-ND - DEMO BOARD FOR LT4356-3
DC1018B-B-ND - DEMO BOARD FOR LT4356-2
DC1018B-A-ND - DEMO BOARD FOR LT4356-1
LT4356-1/LT4356-2
APPLICATIONS INFORMATION
The LT4356 can limit the voltage and current to the load
circuitry during supply transients or overcurrent events.
The total fault timer period should be set to ride through
short overvoltage transients while not causing damage
to the pass transistor. The selection of this N-channel
MOSFET pass transistor is critical for this application.
It must stay on and provide a low impedance path from
the input supply to the load during normal operation and
then dissipate power during overvoltage or overcurrent
conditions.
The following sections describe the overcurrent and the
overvoltage faults, and the selection of the timer capacitor
value based on the required warning time. The selection
of the N-channel MOSFET pass transistor is discussed
next. Auxiliary ampli?er, reverse input, and the shutdown
functions are covered after the MOSFET selection. External
component selection is discussed in detail in the Design
Example section.
Overvoltage Fault
The LTC4356 limits the voltage at the OUT pin during an
overvoltage situation. An internal voltage ampli?er regu-
lates the GATE pin voltage to maintain a 1.25V threshold at
the FB pin. During this period of time, the power MOSFET
is still on and continues to supply current to the load. This
allows uninterrupted operation during short overvoltage
transient events.
When the voltage regulation loop is engaged for longer
than the time-out period, set by the timer capacitor con-
nected from the TMR pin to ground, an overvoltage fault is
Overcurrent Fault
The LT4356 features an adjustable current limit that
protects against short circuits or excessive load current.
During an overcurrent event, the GATE pin is regulated to
limit the current sense voltage across the V CC and SNS
pins to 50mV.
An overcurrent fault occurs when the current limit circuitry
has been engaged for longer than the time-out delay set
by the timer capacitor. The GATE pin is then immediately
pulled low by a 10mA current to GND turning off the
MOSFET. After the fault condition has disappeared and a
cool down period has transpired, the GATE pin is allowed
to pull back up and turn on the pass transistor.
Fault Timer
The LT4356 includes an adjustable fault timer pin. Con-
necting a capacitor from the TMR pin to ground sets the
delay timer period before the MOSFET is turned off. The
same capacitor also sets the cool down period before the
MOSFET is allowed to turn back on after the fault condition
has disappeared.
Once a fault condition, either overvoltage or overcurrent,
is detected, a current source charges up the TMR pin. The
current level varies depending on the voltage drop across
the drain and source terminals of the power MOSFET(V DS ),
which is typically from the V CC pin to the OUT pin. This
scheme takes better advantage of the available Safe
Operating Area (SOA) of the MOSFET than would a ?xed
timer current. The timer function operates down to V CC =
5V across the whole temperature range.
detected. The GATE pin is pulled down to the OUT pin by a
150mA current. After the fault condition has disappeared
and a cool down period has transpired, the GATE pin starts
to pull high again. This prevents the power MOSFET from
being damaged during a long period of overvoltage, such
as during load dump in automobiles.
4356fa
11
相关PDF资料
PDF描述
536511-1 CONN RCEPT RTANG 2MM 24POS 30AU
3AB 125-R FUSE 125MA 250V FAST CERM 3AB
LT4356IS-1#TRPBF IC SURGE STOPPER ADJ 16-SOIC
LT4356HMS-1#TRPBF IC OVERVOLT PROT REG 10-MSOP
RCWL0603R110JQEA RES .11 OHM 1/10W 5% 0603 SMD
相关代理商/技术参数
参数描述
LT4356HDE-2 制造商:Linear Technology 功能描述:MS-Hot Swap/High Voltage, Overvoltage Protection Regulator with Auto-retry
LT4356HDE-2#PBF 功能描述:IC SURGE STOPPER ADJ 12-DFN RoHS:是 类别:过电压,电流,温度装置 >> 电涌抑制 IC 系列:- 产品培训模块:LT4356 Surge Stopper 产品目录绘图:LT4356 Output Graph LT4356 Series 10-MSOP 标准包装:2,500 系列:- 电压 - 工作:4 ~ 80V 电压 - 箝位:27V,可调 技术:混合技术 功率(瓦特):- 电路数:1 应用:自动 封装/外壳:10-TFSOP,10-MSOP(0.118",3.00mm 宽) 供应商设备封装:10-MSOP 包装:带卷 (TR) 配用:DC1018B-C-ND - DEMO BOARD FOR LT4356-3DC1018B-B-ND - DEMO BOARD FOR LT4356-2DC1018B-A-ND - DEMO BOARD FOR LT4356-1
LT4356HDE-2#TRPBF 功能描述:IC SURGE STOPPER ADJ 12-DFN RoHS:是 类别:过电压,电流,温度装置 >> 电涌抑制 IC 系列:- 产品培训模块:LT4356 Surge Stopper 产品目录绘图:LT4356 Output Graph LT4356 Series 10-MSOP 标准包装:2,500 系列:- 电压 - 工作:4 ~ 80V 电压 - 箝位:27V,可调 技术:混合技术 功率(瓦特):- 电路数:1 应用:自动 封装/外壳:10-TFSOP,10-MSOP(0.118",3.00mm 宽) 供应商设备封装:10-MSOP 包装:带卷 (TR) 配用:DC1018B-C-ND - DEMO BOARD FOR LT4356-3DC1018B-B-ND - DEMO BOARD FOR LT4356-2DC1018B-A-ND - DEMO BOARD FOR LT4356-1
LT4356HDE-2PBF 制造商:Linear Technology 功能描述:Surge Protect Adj Regulator 4-80V 60uA
LT4356HDE-3 功能描述:IC REG OVP FAULT TIMER 12DFN RoHS:否 类别:过电压,电流,温度装置 >> 电涌抑制 IC 系列:- 产品培训模块:LT4356 Surge Stopper 产品目录绘图:LT4356 Output Graph LT4356 Series 10-MSOP 标准包装:2,500 系列:- 电压 - 工作:4 ~ 80V 电压 - 箝位:27V,可调 技术:混合技术 功率(瓦特):- 电路数:1 应用:自动 封装/外壳:10-TFSOP,10-MSOP(0.118",3.00mm 宽) 供应商设备封装:10-MSOP 包装:带卷 (TR) 配用:DC1018B-C-ND - DEMO BOARD FOR LT4356-3DC1018B-B-ND - DEMO BOARD FOR LT4356-2DC1018B-A-ND - DEMO BOARD FOR LT4356-1