参数资料
型号: LTC1645IS8#PBF
厂商: Linear Technology
文件页数: 8/24页
文件大小: 329K
描述: IC CTLR HOT SWAP SEQ DUAL 8-SOIC
标准包装: 100
类型: 热交换控制器
应用: 通用
内部开关:
电源电压: 1.2 V ~ 12 V
工作温度: -40°C ~ 85°C
安装类型: 表面贴装
封装/外壳: 8-SOIC(0.154",3.90mm 宽)
供应商设备封装: 8-SOIC
包装: 管件
8
LTC1645
1645fa
Power Supply Ramping
The power supplies on a board are controlled by placing
external N-channel pass transistors in the power paths as
shown in Figure 2. Consult Table 1 for a selection of
N-channel FETs suitable for use with the LTC1645. R
SENSE1
and R
SENSE2
 provide current fault detection and R1 and R2
prevent high frequency oscillation. By ramping the gates
of the pass transistors up and down at a controlled rate,
the transient surge current (I = C " dv/dt) drawn from the
main backplane supply is limited to a safe value when the
board makes connection.
When power is first applied to the chip, the gates of the
N-channels (GATE1 and GATE2 pins) are pulled low. After
the ON pin is held above 0.8V for at least one timing cycle,
the voltage at GATE1 begins to rise with a slope equal to
dv/dt = 10礎/C1 (Figure 3), where C1 is the external
capacitor connected between the GATE1 pin and GND. If
the ON pin is brought above 2V (and the ON pin has been
held above 0.8V for at least one timing cycle), the voltage
at GATE2 begins to rise with a slope equal to dv/dt =
10礎/C2.
The ramp time for each supply is t = (V
CCn
 " Cn)/10礎. If
the ON pin is pulled below 2V for GATE2 or 0.8V for GATE1
(but above 0.4V), a 40礎 current source is connected from
GATEn to GND, and the voltage at the GATEn pin will ramp
down, as shown in Figure 4.
Ringing
Good engineering practice calls for bypassing the supply
rail of any circuit. Bypass capacitors are often placed at the
supply connection of every active device, in addition to one
or more large value bulk bypass capacitors per supply rail.
If power is connected abruptly, the bypass capacitors slow
the rate of rise of voltage and heavily damp any parasitic
resonance of lead or trace inductance working against the
supply bypass capacitors.
The opposite is true for LTC1645 Hot Swap circuits on a
daughterboard. In most cases, on the powered side of the
N-channel FET switches (V
CCn
) there is no supply bypass
capacitor present. An abrupt connection, produced by
plugging a board into a backplane connector, results in a
fast rising edge applied to the V
CCn
 line of the LTC1645.
APPLICATIO S I FOR ATIO
U
U
U
Figure 4. Supply Turning Off
Figure 3. Supply Turning On
Figure 2. Typical Hot Swap Connection
R
SENSE2
Q1
Q2
R2
10&
C2
C
TIMER
C
LOAD1
C
LOAD2
R1
10&
C1
12
1    2
3
8
9
6
5
11
7
13
14
10
4
V
CC1
ON
FAULT
SENSE1
GATE2
V
CC2
V
CC2
V
CC1
V
OUT2
V
OUT1
LTC1645
(14-LEAD)
TIMER
GND
COMP
+
COMPOUT
FB
SENSE2
GATE1
1645 F02
RESET
+
+
R
SENSE1
V
CCn
V
OUTn
V
CCn
+ V
GATE
1645 F03
t
1
t
2
GATEn
SLOPE = 10礎/C
n
V
CCn
V
OUTn
V
CCn
+ V
GATE
1645 F04
t
3
t
4
GATEn
SLOPE = 40礎/C
n
相关PDF资料
PDF描述
ISL61851GCBZ IC USB PWR CTRLR DUAL 8SOIC
XC2C32A-6VQG44I IC CR-II CPLD 32MCELL 44-VQFP
VI-2WY-CX-F1 CONVERTER MOD DC/DC 3.3V 49.5W
VI-27W-CY-F4 CONVERTER MOD DC/DC 5.5V 50W
XC9536XL-10VQG64C IC CPLD 36MCRCELL 10NS 64VQFP
相关代理商/技术参数
参数描述
LTC1645ISPBF 制造商:Linear Technology 功能描述:Hot Swap Controller 2-Channel 12V SOIC14
LTC1646CGN 功能描述:IC CNTRLR HOTSWAP PCIDUAL 16SSOP RoHS:否 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
LTC1646CGN#PBF 功能描述:IC CNTRLR HOTSWAP PCIDUAL 16SSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 热交换 系列:- 标准包装:50 系列:- 类型:热交换控制器 应用:-48V 远程电力系统,AdvancedTCA ? 系统,高可用性 内部开关:无 电流限制:可调 电源电压:11.5 V ~ 14.5 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:10-TFSOP,10-MSOP(0.118",3.00mm 宽) 供应商设备封装:10-MSOP 包装:管件
LTC1646CGN#TR 功能描述:IC CNTRLR HOTSWAP PCIDUAL 16SSOP RoHS:否 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
LTC1646CGN#TRPBF 功能描述:IC CNTRLR HOTSWAP PCIDUAL 16SSOP 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