MIC2085(2004) データシートの表示（PDF） - Micrel
部品番号
コンポーネント説明
メーカー
MIC2085 Datasheet PDF : 28 Pages
| |||
MIC2085/2086
Micrel
Fast Output Discharge for Capacitive Loads
(DIS pin output is low) once the ON pin is deasserted. Figure
In many applications where a switch controller is turned off by
either removing the PCB from the backplane or the ON pin is
reset, capacitive loading will cause the output to retain
voltage unless a ‘bleed’ (low impedance) path is in place in
order to discharge the capacitance. The MIC2086 is equipped
with an internal MOSFET that allows the discharging of any
load capacitance to ground through a 550Ω path. The dis-
charge feature is configured by wiring the DIS pin to the
output (source) of the external MOSFET and becomes active
8(a) illustrates the use of the discharge feature with an
optional resistor (R5) that can be used to provide added
resistance in the output discharge path. For an even faster
discharge response of capacitive loads, the configuration of
Figure 8(b) can be utilized to apply a crowbar to ground
through an external SCR (Q3) that is triggered when the DIS
pin goes low which turns on the PNP transistor (Q2). See the
different “Functional Characteristic” curves for a comparison
of the discharge response configurations.
1V2VIN
ON Signal
C1m1F
R471kW
4 ON
10R.0S5E0%N7SW E2
(PowSeir7P8QA9K12TDMPSO-8)
3
4
19,20 18
VCC SENSE
GATE 17
R102W
R111%30kW
C0.2022mF
V12OVUT@5A
1C5LO0A0DmF
MIC2086
FB 8
R114%4.7kW
DIS 15
*R5
CPOR
0.01CmF3 3
/POR 5
PWRGD 6
GND CFILTER
9,10
2 C0.401mF
DSiogwnnaslstream
1V2VIN
ON Signal
C1m1F
R471kW
4 ON
(a)
10R.0S5E0%N7SW E2
(PowSeir7P8QA9K12TDMPSO-8)
3
4
19,20 18
VCC SENSE
GATE 17
R102W
R111%30kW
C0.2022mF
MIC2086
FB 8
R114%4.7kW
/POR 5 DSiogwnnasl treamR4.64kW
V12OVUT@5A
1C5LO0A0DmF
DIS 15
CPOR GND CFILTER
0.01CmF3 3
9,10
2 C0.401mF
UPC*ARwOdnir5dcdiRtuiheot/iirSoftivnnFTBotaAierlgtelraRunapgrTakieen-leUs85(rOP(5oRa0umDe)W tspiiets.ptuleaootd)ynp=stf=ioeo1r6n1TcmaVilmalstreoity=c.o6m2b0imnse in series
(b)
R1.55kW
0.022CmF5
ZTXQ7288A
R2270W
TCRQ232-4
Figure 8. MIC2086 Fast Discharge of Capacitive Load
M0235-121903
20
January 2004
Share Link: 