HV300/HV310
Timing Diagrams
VSENSE
RSENSE
ILIM
=
contact
bounce
CRAMP
GND
tSTART = 1.2V
VOUT
VIN
IRAMP
VUVL
VOUT
VIN
CRAMP
-48V
tTH = VGS(th)
VGATE
IRAMP
tSTART
tPOR = tSTART + tTH
VRAMP
VRAMP
VGATE
VGS(lim)
VGATE
CRAMP
VGS(th)
tRISE
≈
IRAMP
RSENSE
RFB
VEE
gfs
−
0.9I
LIM
tTH
tPOR
ILIM
CLOAD
1
2
90%
IIN
tLIM ≈ VIN
−
tRISE
ILIM
tRISE
CRAMP
tPWRGD
tPWRGD = V − VGS(lim) −1.2V
(
)
IRAMP
INT
tLIM
active
PWRGD
inactive
VINT is the internally regulated supply voltage and can
range from 9V to 11V.
VGS(th) is the gate threshold voltage of the external pass
transistor and may be obtained from its datasheet.
Initialization
Full On
Limiting
V
GS(lim) is the pass transistor gate-source voltage required
to obtain the limit curent. It is dependent on the pass
transistor’s characteristics and may be obtained from the
transfer characteristics curves on the transistor datasheet.
gfs is the transconductance of the pass transistor and may
be obtained from its datasheet.
RFB is the internal feedback resistor and is 5kΩ nominal.
Absolute Maximum Ratings
VEE reference to VDD pin
+0.3V to -100V
-0.3V to +100V
-40°C to +85°C
VPWRGD referenced to VEE Voltage
Operating Ambient Temperature Range
Operating Junction Temperature
Range
-40°C to +125°C
-65°C to +150°C
-0.3V to +12V
Storage Temperature Range
UV & OV ref to VEE
3