- 您现在的位置：买卖IC网 > Datasheet目录42 > LTC4230CGN#TRPBF (Linear Technology)IC CONTRLLR HOT SWAP TRPL 20SSOP Datasheet资料下载
参数资料
| 型号： | LTC4230CGN#TRPBF |
| 厂商： | Linear Technology |
| 文件页数： | 16/36页 |
| 文件大小： | 384K |
| 描述： | IC CONTRLLR HOT SWAP TRPL 20SSOP |
| 标准包装： | 2,500 |
| 类型： | 热交换控制器 |
| 应用： | 通用 |
| 内部开关： | 无 |
| 电源电压： | 1.7 V ~ 16.5 V |
| 工作温度： | 0°C ~ 70°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 20-SSOP（0.154"，3.90mm 宽） |
| 供应商设备封装： | 20-SSOP |
| 包装： | 带卷 (TR) |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页当前第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页第34页第35页第36页
16
LTC4230
4230f
a start-up check to make sure the supply voltage is above
its 2.3V UVLO threshold (see Time Point 1). If the input
supply voltage is valid, the gate of the external pass
transistor is pulled to ground by the internal 200礎 current
source connected at the GATEn pin. The TIMER pin is held
low by an internal N-channel pull-down transistor (see
M6, LTC4230 Block Diagram) and the FILTER pin voltage
is pulled to ground by an internal 10礎 current source.
Once V
CCn
and ON (the ON pin is >1.314V) are valid, the
LTC4230 checks to make sure that GATEn is OFF (V
GATEn
< 0.25V) at Time Point 2. An internal timing circuit is
enabled and the TIMER pin voltage ramps up at the rate
described by Equation 1. At Time Point 3 (the timing period
programmed by C
TIMER
), the TIMER pin voltage equals
V
TMR
(1.234V). Next, the TIMER pin voltage ramps down
to Time Point 4 where the LTC4230 performs two checks:
(1) FILTER pin voltage is low (V
FILTER
< 1.19V) and (2)
FAULT pin voltage is high (V
FAULT
> 1.284V). If both
conditions are met, the LTC4230 begins a second timing
(soft-start) cycle.
Second Timing (Soft-Start) Cycle
At the beginning of the second timing cycle (Time Point 5),
the LTC4230s FAST COMPn is armed and an internal
10礎 current source working with an internal charge
pump provides the gate drive to the external pass transis-
tor. An expression for the GATEn voltage slew rate is given
by Equation 3:
V
SlewRate
dV
dt
A
C
GATE
GATE
GATE
n
n
n
,
=
?/DIV>
10
(3)
where C
GATEn
= Power MOSFET gate input capacitance
(C
ISS
) for Channel n.
For example, a Si4410DY (a 30V N-channel power MOSFET)
exhibits an approximate C
GATE
of 3300pF at V
GS
= 10V. The
LTC4230s GATEn voltage rate-of-change (slew rate) for
this example would be:
V
SlewRate
dV
dt
A
pF
V
ms
GATE
GATE
n
n
,
.
=
?/DIV>
=
10
3300
3 03
The inrush current being delivered to the load while the
GATEn is ramping is dependent on C
LOADn
and C
GATEn
.
Equation 4 gives an expression for the inrush current
during the second timing cycle:
I
dV
dt
C
A
C
C
INRUSH
GATE
LOAD
LOAD
GATE
=
= ?/DIV>
n
n
n
n
"
"
10
(4)
For example, if C
GATEn
= 3300pF and C
LOADn
= 2000礔, the
inrush current charging C
LOADn
is:
I
A
F
F
A
INRUSH
= ?/DIV>
?/DIV>
?/DIV>
=
10
2000
0 0033
6 06
"
.
.
(5)
At Time Point 7, the output voltage trips FBCOMPns
threshold, signaling an output voltage power good con-
dition. RESET 2 and RESET 3 pull high. At Time Point 8,
RESET 1 asserts high, SLOW COMP is armed and the
LTC4230 enters a fault monitor mode.
SOFT-START WITH CURRENT LIMITING
During the second timing cycle, the inrush current is
described by Equation 4. Note that there is a one-to-one
correspondence in the inrush current to C
LOADn
. If the
inrush current is large enough to cause a voltage drop
greater than 50mV across the sense resistor, an internal
servo loop controls the operation of the 10礎 current
source at the GATEn pin to regulate the load current to:
I
mV
R
LIMIT SOFTSTART
SENSE
(
)n
n
=
50
(6)
For example, the inrush current is limited to 5A when
R
SENSEn
= 0.01&.
In this fashion, the inrush current is controlled and C
LOADn
is charged up slowly during the soft-start cycle.
The timing diagram in Figure 6 illustrates the operation of
the LTC4230 in a normal power-up sequence with limited
inrush current as described by Equation 6. At Time Point 5,
the GATE pin voltage begins to ramp indicating that the
power MOSFET is beginning to charge C
LOADn
. At Time
Point 5, the inrush current causes a 50mV voltage drop
across R
SENSEn
and an internal servo loop engages, limit-
ing the inrush current to a fixed level. At Time Point 6, the
GATEn pin voltage continues to ramp as C
LOADn
charges
until V
OUTn
reaches its final value. The charging current
APPLICATIO S I FOR ATIO
U
U
U
相关PDF资料 |
PDF描述 |
|---|---|
| LTC4232CDHC#TRPBF | IC CTLR HOT SWAP 5A 16-DFN |
| LTC4240IGN#TRPBF | IC CTRLR HOTSWAP CPCI I2C 28SSOP |
| LTC4241IGN#PBF | IC CTRLR HOTSWAP 3.3V AUX 20SSOP |
| LTC4242CUHF#TRPBF | IC CNTRLR HOT SWAP 38-QFN |
| LTC4244CGN-1#TRPBF | IC CTRLR HOTSWAP PCI 20-SSOP |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LTC4230IGN | 功能描述:IC CONTRLLR HOT SWAP TRPL 20SSOP RoHS:否 类别:集成电路 (IC) >> PMIC - 热交换 系列:- 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:119 系列:- 类型:热交换控制器 应用:通用型，PCI Express? 内部开关:无 电流限制:- 电源电压:3.3V，12V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:80-TQFP 供应商设备封装:80-TQFP（12x12） 包装:托盘 产品目录页面:1423 (CN2011-ZH PDF) |
| LTC4230IGN#PBF | 功能描述:IC CONTRLLR HOT SWAP TRPL 20SSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 热交换 系列:- 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:119 系列:- 类型:热交换控制器 应用:通用型，PCI Express? 内部开关:无 电流限制:- 电源电压:3.3V，12V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:80-TQFP 供应商设备封装:80-TQFP（12x12） 包装:托盘 产品目录页面:1423 (CN2011-ZH PDF) |
| LTC4230IGN#TR | 功能描述:IC CONTRLLR HOT SWAP TRPL 20SSOP RoHS:否 类别:集成电路 (IC) >> PMIC - 热交换 系列:- 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:119 系列:- 类型:热交换控制器 应用:通用型，PCI Express? 内部开关:无 电流限制:- 电源电压:3.3V，12V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:80-TQFP 供应商设备封装:80-TQFP（12x12） 包装:托盘 产品目录页面:1423 (CN2011-ZH PDF) |
| LTC4230IGN#TRPBF | 功能描述:IC CONTRLLR HOT SWAP TRPL 20SSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 热交换 系列:- 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:119 系列:- 类型:热交换控制器 应用:通用型，PCI Express? 内部开关:无 电流限制:- 电源电压:3.3V，12V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:80-TQFP 供应商设备封装:80-TQFP（12x12） 包装:托盘 产品目录页面:1423 (CN2011-ZH PDF) |
| LTC4232CDHC#PBF | 功能描述:IC CTLR HOT SWAP 5A 16-DFN RoHS:是 类别:集成电路 (IC) >> PMIC - 热交换 系列:- 产品培训模块:Obsolescence Mitigation Program 标准包装:100 系列:- 类型:热插拔开关 应用:通用 内部开关:是 电流限制:可调 电源电压:9 V ~ 13.2 V 工作温度:-40°C ~ 150°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-EP（3x3） 包装:管件 |
发布紧急采购，3分钟左右您将得到回复。