- 您现在的位置：买卖IC网 > PDF目录22144 > LTC1644IGN#TR (Linear Technology)IC CONTROLLER HOT SWAP 20-SSOP PDF资料下载
参数资料
| 型号： | LTC1644IGN#TR |
| 厂商： | Linear Technology |
| 文件页数： | 16/24页 |
| 文件大小： | 447K |
| 描述： | IC CONTROLLER HOT SWAP 20-SSOP |
| 标准包装： | 2,500 |
| 类型： | 热交换控制器 |
| 应用： | CompactPCI? |
| 内部开关： | 无 |
| 电源电压： | 3.3V，5V，±12V |
| 工作温度： | -40°C ~ 85°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) |
| 其它名称： | LTC1644IGNTR |
LTC1644
16
1644f
APPLICATIO S I FOR ATIO
U
U
U
Calculating R
SENSE
An equivalent circuit for one of the LTC1644s circuit
breakers useful in calculating the value of the sense
resistor is shown in Figure 7. To determine the most
appropriate value for the sense resistor first requires the
maximum current required by the load under worst-case
conditions.
+
14
LTC1644*
1644 F07
*ADDITIONAL DETAILS OMITTED FOR CLARITY
V
CB(MAX)
= 70mV
V
CB(NOM)
= 55mV
V
CB(MIN)
= 40mV
13
5V
SENSE
5V
IN
R
SENSE
I
LOAD(MAX)
5V
IN
V
CB
+
Two other parameters affect the value of the sense resis-
tor. First is the tolerance of the LTC1644s circuit breaker
threshold. The LTC1644s nominal circuit breaker thresh-
old is V
CB(NOM)
= 55mV; however, it exhibits ?5mV
tolerance over process and temperature. Second is the
tolerance (RTOL) in the sense resistor. Sense resistors are
available in RTOLs of ?%, ?% and ?% and exhibit
temperature coefficients of resistance (TCRs) between
?5ppm/癈 and ?00ppm/癈. How the sense resistor
changes as a function of temperature depends on the I
2
R
power being dissipated by it. The power rating of the sense
resistor should accommodate steady-state fault current
levels so that the component is not damaged before the
circuit breaker trips.
The first step in calculating the value of R
SENSE
is based on
I
LOAD(MAX)
and the lower limit for the circuit breaker
threshold, V
CB(MIN)
. The maximum value for R
SENSE
in this
case is expressed by Equation 6:
R
V
I
SENSE
CB MIN
LOAD MAX
=
( )
( )
(6)
Figure 7. Circuit Breaker Equivalent
Circuit for Calculating R
SENSE
The second step is to determine the nominal value of
the sense resistor which is dependent on its tolerance
(RTOL = ?%, ?%, or ?%) and standard sense resistor
values. Equation 7 can be used to calculate the nominal
value from the maximum value found by Equation 6:
R
R
RTOL
SENSE N M
SENSE MAX
( )
( )
0
1
100
=
+
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
(7)
Often, the result of Equation 7 may not yield a standard
sense resistor value. In this case, two sense resistors with
the same RTOL can be connected in parallel to yield
R
SENSE(NOM)
.
The last step requires calculating a new value for I
TRIP(MAX)
(I
TRIP(MAX,NEW)
) based on a minimum value for R
SENSE
(R
SENSE(MIN)
) and the upper limit for the circuit breaker
threshold, V
CB(MAX)
. The new value for I
TRIP(MAX,NEW)
is
given by Equation 8:
I
V
R
TRIP MAXNEW
CB MAX
SENSE MIN
( ,
)
( )
( )
=
(8)
where R
R
RTOL
SENSE MIN
SENSE NOM
( )
(
)
=
"
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
1
100
Table 4 lists I
TRIP(MIN)
and I
TRIP(MAX)
versus some sug-
gested values of R
SENSE
. Table 8 lists manufacturers and
part numbers for these resistor values.
Table 4. I
TRIP
vs R
SENSE
Table
R
SENSE
(1% RTOL)
I
TRIP(MIN)
I
TRIP(MAX)
0.005&
7.92A
14.14A
0.007&
5.66A
10.10A
0.011&
3.60A
6.43A
0.028&
1.41A
2.53A
0.055&
0.72A
1.29A
相关PDF资料 |
PDF描述 |
|---|---|
| EPM7256EGI192-20 | IC MAX 7000 CPLD 256 192-PGA |
| RSC30DRAH-S734 | CONN EDGECARD 60POS .100 R/A PCB |
| R2S12-1524/H | CONV DC/DC 2W 15VIN 24VOUT SMD |
| RMC30DRAH-S734 | CONN EDGECARD 60POS .100 R/A PCB |
| R2S12-1512/H | CONV DC/DC 2W 15VIN 12VOUT SMD |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LTC1645CS | 功能描述:IC CTRLR SEQ HOTSWAP DUAL 14SOIC 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 |
| LTC1645CS#PBF | 功能描述:IC CTLR HOT SWAP SEQ DUAL 14SOIC 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 |
| LTC1645CS#TR | 功能描述:IC CTRLR SEQ HOTSWAP DUAL 14SOIC 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 |
| LTC1645CS#TRPBF | 功能描述:IC CTRLR SEQ HOTSWAP DUAL 14SOIC 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 |
| LTC1645CS8 | 功能描述:IC CTRLR SEQ HOTSWAP DUAL 8SOIC 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 |
发布紧急采购，3分钟左右您将得到回复。