MAX14586/MAX14590
High-Current Overvoltage Protectors
with Adjustable OVLO
Functional Diagram
IN
IN
OUT
OUT
CHARGE
PUMP
MAX14586
MAX14590
TEMPERATURE
FAULTS
LOGIC
V
BG
CONTROL
REFERENCE
SEL
OVLO
GND
Overvoltage Lockout (OVLO)
The MAX14586 has a 7V (typ) overvoltage threshold. The
MAX14590 has a 15V (typ) overvoltage threshold.
Detailed Description
The MAX14586/MAX14590 overvoltage protection devices
feature a low on-resistance (R ) internal FET and protect
ON
Thermal Shutdown Protection
The devices feature thermal shutdown circuitry. The inter-
nal FET turns off when the junction temperature exceeds
+150NC (typ). The device exits thermal shutdown after
the junction temperature cools by 20NC (typ).
low-voltage systems against voltage faults up to +36V. If
the input voltage exceeds the overvoltage threshold, the
internal FET is turned off to prevent damage to the pro-
tected components. The 15ms debounce time prevents
false turn-on of the internal FET during startup.
Applications Information
Device Operation
The devices have timing logic that controls the turn-on
IN Bypass Capacitor
For most applications, bypass IN to GND with a 1FF
ceramic capacitor as close as possible to the device
to enable Q15kV (HBM) ESD protection on IN. If Q15kV
(HBM) ESD is not required, there is no capacitor required
at IN. If the power source has significant inductance due
to long lead length, take care to prevent overshoots due
to the LC tank circuit and provide protection if necessary
to prevent exceeding the +40V absolute maximum rating
on IN.
of the internal FET. If V < V
, the internal
IN
OVLO_THRESH
charge pump is enabled. The charge-pump startup, after
a 15ms debounce delay, turns on the internal FET (see
the Functional Diagram). After the debounce time, soft-
start limits the FET inrush current for 15ms (typ). At any
time, if V rises above V
nected from IN.
, OUT is discon-
IN
OVLO_THRESH
Internal Switch
The devices incorporate an internal FET with a 48mI
OUT Output Capacitor
The slow turn-on time provides a soft-start function that
allows the devices to charge an output capacitor up to
1000FF without turning off due to an overcurrent condition.
(typ) R . The FET is internally driven by a charge pump
that generates a necessary gate voltage above IN. The
internal FET can pass more than 5A inrush current.
ON
����������������������������������������������������������������� Maxim Integrated Products
7
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
