LT4256 LINER [Linear Technology], LT4256 Datasheet - Page 6

• Manufacturer Part Number: LT4256
• Description: UV, OV and Reverse Supply Protection Controller Low Operating Current: 125?A
• Manufacturer: LINER [Linear Technology]

LTC4365
PIN FUNCTIONS
Exposed Pad: Connect to device ground.
FAULT: Fault Indication Output. This high voltage open drain
output is pulled low if UV is below its monitor threshold,
if OV is above its monitor threshold, if SHDN is low, or if
V
GATE: Gate Drive Output for External N-channel MOSFETs.
An internal charge pump provides 20μA of pull-up current
and up to 9.8V of enhancement to the gate of an external
N-channel MOSFET.
When turned off, GATE is pulled just below the lower of
V
cally connected to V
GND: Device Ground.
OV: Overvoltage Comparator Input. Connect this pin to an
external resistive divider to set the desired V
fault threshold. Input to an accurate, fast (1μs) compara-
tor with a 0.5V rising threshold and 25mV of hysteresis.
When OV rises above its threshold, a 50mA current sink
pulls down on the GATE output. When OV falls back below
0.475V, and after a 36ms recovery delay waiting period,
the GATE charge pump is enabled. The low leakage current
of the OV input allows the use of large valued resistors for
the external resistive divider. Connect to GND if unused.
SHDN: Shutdown Control Input. SHDN high enables the
GATE charge pump which in turn enhances the gate of an
external N-channel MOSFET. A low on SHDN generates a
6
IN
IN
has not risen above V
or V
OUT
. When V
IN
IN
.
goes negative, GATE is automati-
IN(UVLO)
.
IN
overvoltage
pull down on the GATE output with a 90μA current sink and
places the LTC4365 in low current mode (10μA). If unused,
connect to V
60V, use a current limiting resistor of at least 100k.
UV: Undervoltage Comparator Input. Connect this pin
to an external resistive divider to set the desired V
undervoltage fault threshold. Input to an accurate, fast
(1μs) comparator with a 0.5V falling threshold and 25mV
of hysteresis. When UV falls below its threshold, a 50mA
current sink pulls down on the GATE output. When UV
rises back above 0.525V, and after a 36ms recovery
delay waiting period, the GATE charge pump is enabled.
The low leakage current of the UV input allows the use
of large valued resistors for the external resistive divider.
If unused, connect to V
goes below ground, or if V
limiting resistor of at least 100k.
V
–40V to 60V. Operating range: 2.5V to 34V.
V
age at the output side of the external N-channel MOSFET.
The GATE charge pump voltage is referenced to V
is used as the charge pump input when V
than approximately 6.5V.
IN
OUT
: Power Supply Input. Maximum protection range:
: Output Voltage Sense Input. This pin senses the volt-
IN
. If V
IN
goes below ground, or if V
IN
. While connected to V
IN
rings to 60V, use a current
OUT
IN
is greater
IN
rings to
, if V
OUT
4365f
. It
IN
IN