OMO ElectronicOMO Electronic
Expand menu
Hello, Sign inMy Account
0 Cart

MAX14527ETA+T

P1-P3P4-P6P7-P7
MAX14527/MAX14528
Adjustable Overvoltage Protector
with High Accuracy
4 _______________________________________________________________________________________
Typical Operating Characteristics
(T
A
= +25°C, unless otherwise noted.)
0
20
30
40
50
60
70
80
90
0 7 14 21 28
IN SUPPLY CURRENT
vs. IN VOLTAGE
MAX14527/8 toc01
IN VOLTAGE (V)
IN SUPPLY CURRENT (µA)
10
T
A
= +85°C
T
A
= -40°C
T
A
= +25°C
POWER-UP RESPONSE
MAX14527/8 toc07
10ms/div
V
IN
5V/div
V
OUT
5V/div
I
OUT
100mA/div
OVERVOLTAGE FAULT RESPONSE
MAX14527/8 toc08
1μs/div
V
IN
5V/div
V
OUT
5V/div
I
OUT
50mA/div
Detailed Description
The MAX14527/MAX14528 overvoltage protection
devices feature a low R
ON
internal FET and protect low-
voltage systems against voltage faults up to +28V. If
the input voltage exceeds the overvoltage threshold,
the internal FET is turned off to prevent damage to the
protected components. The 15ms debounce time pre-
vents false turn-on of the internal FET during startup.
Device Operation
The MAX14527/MAX14528 have timing logic that
controls the turn-on of the internal FET. If V
IN
<
V
OVLO_THRESH
, the internal charge pump is enabled.
The charge-pump startup, after a 15ms debounce
delay, turns on the internal FET (see the
Functional
Diagram
). At any time, if V
IN
rises above V
OVLO_
THRESH
, OUT is disconnected from IN.
MAX14527/MAX14528
Adjustable Overvoltage Protector
with High Accuracy
_______________________________________________________________________________________ 5
Pin Description
Functional Diagram
OUT
OUT
IN
IN
OVLO
GND
CHARGE
PUMP
LOGIC
CONTROL
SEL
V
BG
REFERENCE
+
-
TEMPERATURE
FAULTS
MAX14527
MAX14528
PIN
NAME
FUNCTION
1, 2 IN
Voltage Input. Bypass IN with a 1µF ceramic capacitor as close as possible to the device to obtain ±15kV
Human Body Model (HBM) ESD protection. Connect all the IN pins together for proper operation. IN is
protected to ±2kV HBM when IN is not bypassed with a capacitor to GND.
3
OVLO
External OVLO Adjustment. Connect OVLO to GND when using the internal threshold. Connect a resistor-
divider to OVLO to set a different OVLO threshold; this external resistor-divider is completely independent
from the internal threshold.
4, 5 I.C. Internally Connected. Do not connect. Leave I.C. unconnected.
6 GND Ground
7, 8 OUT Output Voltage. Output of internal switch. Connect all the OUT outputs together for proper operation.
—EP
Exposed Pad. Connect exposed pad to ground. For enhanced thermal dissipation, connect EP to a copper
area as large as possible. Do not use EP as a sole ground connection.
MAX14527/MAX14528
Internal Switch
The MAX14527/MAX14528 incorporate an internal FET
with a 100mΩ (typ) R
ON
. The FET is internally driven by
a charge pump that generates a necessary gate volt-
age above IN. The internal FET is capable of passing
more than 5A inrush current.
Overvoltage Lockout (OVLO)
The MAX14527 has a 5.75V (typ) overvoltage threshold
(OVLO).The MAX14528 has a 6.76V (typ) OVLO
threshold.
Thermal-Shutdown Protection
The MAX14527/MAX14528 feature thermal shutdown
circuitry. The internal FET turns off when the junction
temperature exceeds +150°C (typ). The device exits
thermal shutdown after the junction temperature cools
by 20°C (typ).
Applications Information
IN Bypass Capacitor
For most applications, bypass IN to GND with a 1µF
ceramic capacitor as close as possible to the device to
enable ±15kV (HBM) ESD protection on IN. If ±15kV
(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 pre-
vent overshoots due to the LC tank circuit and provide
protection if necessary to prevent exceeding the +30V
absolute maximum rating on IN.
OUT Output Capacitor
The slow turn-on time provides a soft-start function that
allows the MAX14527/MAX14528 to charge an output
capacitor up to 1000µF.
External OVLO Adjustment Functionality
If OVLO is connected to ground, the internal OVLO
comparator uses the internally set OVLO value.
If an external resistor-divider is connected to OVLO
and V
OVLO
exceeds the OVLO select voltage,
V
OVLO_ SELECT
, the internal OVLO comparator reads
the IN fraction fixed by the external resistor divider. R
1
=
1MΩ is a good starting value for minimum current con-
sumption. Since V
IN_OVLO
, V
OVLO_THRESH
, and R
1
are
known, R
2
can be calculated from the following formula:
This external resistor-divider is completely independent
from the internal resistor-divider.
ESD Test Conditions
ESD performance depends on a number of conditions.
The MAX14527/MAX14528 are specified for ±15kV
(HBM) typical ESD resistance on IN when IN is
bypassed to ground with a 1µF ceramic capacitor.
HBM ESD Protection
Figure 2a shows the Human Body Model, and Figure
2b shows the current waveform it generates when dis-
charged into a low impedance. This model consists of a
100pF capacitor charged to the ESD voltage of interest,
which is then discharged into the device through a
1.5kΩ resistor.
VV
R
R
IN_OVLO OVLO_THRESH
1
2
=×+
⎡
⎣
⎢
⎤
⎦
⎥
1
Adjustable Overvoltage Protector
with High Accuracy
6 _______________________________________________________________________________________
CHARGE-CURRENT-
LIMIT RESISTOR
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
C
s
100pF
R
C
1M
Ω
R
D
1.5k
Ω
HIGH-
VOLTAGE
DC
SOURCE
DEVICE
UNDER
TEST
Figure 2a. Human Body ESD Test Model
I
P
100%
90%
36.8%
t
RL
TIME
t
DL
CURRENT WAVEFORM
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
I
R
10%
0
0
AMPERES
Figure 2b. Human Body Current Waveform
P1-P3P4-P6P7-P7

MAX14527ETA+T

Mfr. #:
Buy MAX14527ETA+T
Manufacturer:
Maxim Integrated
Description:
Supervisory Circuits Over Volt Protector w/Internal N-FET
Lifecycle:
New from this manufacturer.
Delivery:
DHL FedEx Ups TNT EMS
Payment:
T/T Paypal Visa MoneyGram Western Union

Products related to this Datasheet