ISL6140 Intersil Corporation, ISL6140 Datasheet - Page 15

• Manufacturer Part Number: ISL6140
• Description: Negative Voltage Hot Plug Controller
• Manufacturer: Intersil Corporation

Optional Components
D1 is a voltage suppressor; SMAT70A or equivalent
D2 and D3 are DRAIN diodes; the ISL6150 (H version) uses
both D2 and D3; the ISL6140 (L version) uses just D2. If
neither is used, short the path of either, to connect the
DRAIN pin to C2 and Q1. The 1N4148 is a typical diode.
SW1 is a push-button switch, that can manually reset the
fault latch after an Over-Current shutdown. It can also be
replaced by a transistor switch.
R10 and C4 are used to filter the VDD voltage, such that
small transients on the input supply do not trigger UV or OV.
R7 and C3 are used to delay the Over-Current shutdown. R7
should be shorted, if not used. See the Over-Current section
for more details.
R8 is a pull-up resistor for PWRGD, if there is no other
component acting as a pull-up device. An LED can also be
placed in series with R8, if desired. See Figure 8.
CL is any extra output Load capacitance, which can also be
considered input capacitance for the external module.
-V IN
GND
GND
(SHORT PIN)
NFET*
(INSTEAD
OF SW1)
G
C4*
SW1
D1*
R11
R12
15
(see text for when they should be used)
FIGURE 29. ISL6140/50 OPTIONAL COMPONENTS (SHOWN WITH *)
R5
R4
R6*
UV
OV
V
V
DD
EE
ISL6140, ISL6150
R10*
C3*
R1
R7*
SENSE
ISL6140 (L)
C1
R6 is used to add more hysteresis to the UV threshold,
which already has a built-in 20mV hysteresis. With R6, the
new thresholds with a rising and falling input are:
Since R6 is connected directly to the GATE output, it will
reduce the available gate current, which will reduce the dv/dt
across the MOSFET and hence the inrush current. The
value of R6 should be kept as high as possible (greater than
500K recommended) so that it does not drag down the
GATE voltage below the value required to ensure the
MOSFET is fully enhanced.
Vuv rising
Vuv falling
GATE
(
Q1
(
R2
R3
)
)
D2*
=
=
PWRGD
C2
VUVL
VUVH
DRAIN
•


•
R5 R6
------------------------------------------------------------------------------
D3*


R5 R6
------------------------------------------------------------------------------
•
•
+
R4 R6
R5 R6
+
•
•
R4 R6
R5 R6
R8*
•
•
+
R4 R5
+
•
R4 R5


•
–
Vgate
-V OUT


CL*
•
GND


R4
------- -
R6

