?/DIV>
=
The closest standard 1% value for R1 = 698k&.
Using standard 1% resistor values, the circuits
nominal UV and OV thresholds are:
V
UV
= 36.5V
V
OV
= 71.2V
Good general engineering design practices must
consider   the   tolerances   associated   with   these
parameters, including but not limited to, power supply
tolerance, undervoltage and overvoltage threshold
tolerances, and the tolerances of the external passive
components.
Programmable UVLO Hysteresis (MIC2595 and
MIC2595R)
The MIC2595 and the MIC2595R devices have user-
programmable hysteresis by means of the ON and
OFF pins (Pins 4 and 3, respectively). This allows
setting the MIC2595/MIC2595R to turn on at a voltage
V1, and not turn off until a second voltage V2, where
V2 < V1. This can significantly simplify dealing with
source impedances in the supply buss while at the
same   time   increasing   the   amount   of   available
operating time from a loosely regulated power rail (for
example, a battery supply). The MIC2595/MIC2595R
holds the output off until the voltage at the ON pin is
above its V
ONH
threshold value given in the Electrical
Characteristics table. Once the output has been
enabled by the ON pin, it will remain on until the
voltage at the OFF pin falls below its respective V
OFFL
threshold value, or the part turns off due to an external
fault condition. Should either event occur, the GATE
pin is immediately pulled low and will remain low until
the ON pin voltage once again rises above its V
ONH
threshold. The circuits turn-on and turn-off voltage
levels are set using the resistor divider R1, R2, and
R3 similar to the Typical Application circuit and the
equations to set the trip points are shown below. For
the following example, the circuits ON threshold is set
to V
ON
= 40V and the circuits OFF threshold is set to
V
OFF
= 35V.
)
(
)
R3
R2
R3
R2
R1
(typ)
V
V
R3
R3
R2
R1
(typ)
V
V
OFFL
OFF
ONH
ON
+
+
+
?/DIV>
=
+
+
?/DIV>
=
Given V
OFF
, V
ON
, and any one of the resistor values,
the remaining two resistor values can be readily
determined. A suggested value for R3 is selected to
provide approximately 100礎(chǔ) (or more) of current
through the voltage divider chain at V
DD
= V
OFF
. This
yields the following as a starting point:
12.23k&
100礎(chǔ)
1.223V
100礎(chǔ)
(typ)
V
R3
OFFL
=
=
=
The closest standard 1% value for R3 = 12.4k&.
Solving for R2 and R1 yields:
1.77k&
1
35V
40V
12.4k&
R2
1
V
V
R3
R2
OFF
ON
=
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
=
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
?/DIV>
=
The closest standard 1% value for R2 = 1.78k&.
Lastly, the value for R1 is calculated:
)
391.38k&
R1
1.78k&
1.223V
1.223V
40V
12.4k&
R1
R2
1.223V
1.223V
V
R3
R1
ON
=
?/DIV>
=
?/DIV>
=
The closest standard 1% value for R1 = 392k&.
Using standard 1% resistor values, the circuits
nominal ON and OFF thresholds are:
V
ON
= 40.1V
V
OFF
= 35V
Good general engineering design practices must
consider   the   tolerances   associated   with   these
parameters, including but not limited to, power supply
tolerance, undervoltage and overvoltage threshold
tolerances, and the tolerances of the external passive
components.
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
MIC2595R-2YM |
功能描述:熱插拔功率分布 Negative Voltage Hot-Swap Controller - Lead Free
RoHS:否 制造商:Texas Instruments 產(chǎn)品:Controllers & Switches 電流限制: 電源電壓-最大:7 V 電源電壓-最小:- 0.3 V 工作溫度范圍: 功率耗散: 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:MSOP-8 封裝:Tube |
MIC2595R-2YM TR |
功能描述:熱插拔功率分布 Negative Voltage Hot-Swap Controller - Lead Free
RoHS:否 制造商:Texas Instruments 產(chǎn)品:Controllers & Switches 電流限制: 電源電壓-最大:7 V 電源電壓-最小:- 0.3 V 工作溫度范圍: 功率耗散: 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:MSOP-8 封裝:Tube |
MIC2595R-2YM-TR |
功能描述:Hot Swap Controller, Sequencer 1 Channel -48V 14-SOIC 制造商:microchip technology 系列:- 包裝:剪切帶(CT) 零件狀態(tài):停產(chǎn) 類型:熱交換控制器,序列發(fā)生器 通道數(shù):1 內(nèi)部開(kāi)關(guān):無(wú) 應(yīng)用:-48V 特性:自動(dòng)重試 可編程特性:限流,故障超時(shí),UVLO 電壓 - 電源:-80 V ~ -19 V 電流 - 輸出(最大值):- 工作溫度:-40°C ~ 85°C 電流 - 電源:4mA 安裝類型:表面貼裝 封裝/外殼:14-SOIC(0.154",3.90mm 寬) 供應(yīng)商器件封裝:14-SOIC 功能引腳:CFILTER,CNLD,DRAIN,PGTIMER,OFF,ON,/PWRGD1,/PWRGD2,/PWRGD3 標(biāo)準(zhǔn)包裝:1 |
MIC2596-1BTS |
功能描述:IC SWITCH HOT SWAP DUAL 20-TSSOP RoHS:否 類別:集成電路 (IC) >> PMIC - 熱交換 系列:- 產(chǎn)品培訓(xùn)模塊:Obsolescence Mitigation Program 標(biāo)準(zhǔn)包裝:100 系列:- 類型:熱插拔開(kāi)關(guān) 應(yīng)用:通用 內(nèi)部開(kāi)關(guān):是 電流限制:可調(diào) 電源電壓:9 V ~ 13.2 V 工作溫度:-40°C ~ 150°C 安裝類型:表面貼裝 封裝/外殼:10-WFDFN 裸露焊盤 供應(yīng)商設(shè)備封裝:10-TDFN-EP(3x3) 包裝:管件 |
MIC2596-1BTS TR |
功能描述:IC SWITCH HOT SWAP DUAL 20-TSSOP RoHS:否 類別:集成電路 (IC) >> PMIC - 熱交換 系列:- 產(chǎn)品培訓(xùn)模塊:Obsolescence Mitigation Program 標(biāo)準(zhǔn)包裝:100 系列:- 類型:熱插拔開(kāi)關(guān) 應(yīng)用:通用 內(nèi)部開(kāi)關(guān):是 電流限制:可調(diào) 電源電壓:9 V ~ 13.2 V 工作溫度:-40°C ~ 150°C 安裝類型:表面貼裝 封裝/外殼:10-WFDFN 裸露焊盤 供應(yīng)商設(shè)備封裝:10-TDFN-EP(3x3) 包裝:管件 |