17
LTC4230
 4230f
reduces, and the internal servo loop disengages. At the
end of the soft-start cycle (Time Point 8), all RESETn are
high and all SLOW COMPn are armed.
Power-Off Cycle
As shown at Time Point 9, an external hard reset is initiated
by pulling the ON pin low (V
ON
 < 1.234V). All GATEn pin
voltages are ramped to ground by the internal 200礎
current sources, discharging C
GATEn
 and turning off the
pass transistors. As C
LOADn
 discharges, the output voltage
crosses FBCOMPns threshold, signaling a power bad
condition at Time Point 10. RESETn then asserts low.
1
3
7
6
5
8
4
FIRST TIMING CYCLE
20礎 PULL-UP
20礎 PULL-UP
LOAD CURRENT IS REGULATING AT 50mV/R
SENSEn
4230 F06
NORMAL MODE
SECOND TIMING
CYCLE
CHECK FOR FILTER LOW (< V
REF
)
CHECK FOR FAULT HIGH (> V
REF
 + 50mV)
2
CHECK FOR GATEn < 0.25V
FAST COMPARATOR
ARMED
IF ON IS LOW AND
V
FBn
 < 1.234V,
RESET 1, RESET 2 and RESET 3
PULL LOW, RESPECTIVELY
ON
TIMER
GATEn
V
OUTn
I
LOADn
GATEn
V
OUTn
RESET 1
RESET 2,
RESET 3
10礎 PULL-UP
200礎 PULL-DOWN
SLOW COMPARATOR ARMED
9
10
POWER GOOD
(V
FBn
 > 1.237V)
POWER BAD
(V
FBn
 < 1.234V)
200礎 PULL-DOWN
Figure 6. Normal Power-Up Sequence (with Current Limiting in Second Timing Cycle)
FREQUENCY COMPENSATION AT SOFT-START
If the external gate input capacitance (C
ISS
) is greater than
600pF, no external gate capacitor is required at GATEn to
stabilize the internal current-limiting loop during soft-
start. Otherwise, connect an external gate capacitor be-
tween the GATEn and GND pins to increase the total gate
capacitance above 600pF. The servo loop that controls the
external MOSFET during current limiting has a unity-gain
frequency of about 105kHz and phase margin of 80?for
external MOSFET gate input capacitances to 2.5nF.
APPLICATIO  S I FOR  ATIO
U
U
U
相关PDF资料
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
LTC4245CG#TRPBF IC CNTRLR HOT SWAP 36-SSOP
LTC4251-2CS6#TRPBF IC CTRLR HOTSWAP NEGVOLT SOT23-6
LTC4252A-1IMS#TRPBF IC CNTRLR HOTSWAP NEGVOLT 10MSOP
相关代理商/技术参数
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
LTC4232CDHC#TRPBF 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
LTC4232IDHC#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: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)
LTC4232IDHC#TRPBF 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: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)