Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect device reliability.
Operating Ambient Temperature Range ........... -40NC to +85NC
Maximum Junction Temperature.....................................+150NC
Storage Temperature Range............................ -60NC to +150NC
Lead Temperature (soldering, 10s) ................................+300NC
Soldering Temperature (reflow) ......................................+260NC
PACKAGE THERMAL CHARACTERISTICS (Note 2)
TQFN
Junction-to-Case Thermal Resistance (B
JC
) ...................30NC/W
Junction-to-Ambient Thermal Resistance (B
JA
) ............... ...2NC/W
Note 2:
Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-
layer board. For detailed information on package thermal considerations, refer to
www.maxim-ic.com/thermal-tutorial.
ELECTRICAL CHARACTERISTICS
(V
IN
= 12V, V
ON1
= 2V, V
ON2
= V
PRESDET
= 0V, R
CB
= 40kI, T
A
= T
J
= -40NC to +85NC, unless otherwise noted. Typical values are
at T
A
= +25NC.) (Note 3)
PARAMETER
Input Supply Voltage Range
Input Supply Current
Default Undervoltage Lockout
Default Undervoltage Lockout
Hysteresis
ON1 Turn-On Threshold
ON1 Turn-On Threshold
Hysteresis
ON1 Input Bias Current
CURRENT LIMIT
R
CB
= 40kI
Circuit-Breaker Accuracy
(At Startup)
Slow-Comparator Response
Time (Note 4)
MOSFET
Total On-Resistance
LOGIC INPUTS (ON2,
PRESDET)
Low Voltage Input
High Voltage Input
Input Current
2
V
IL
V
IH
I
IN
2.7V < V
IN
< 18V
2.7V < V
IN
< 18V
V
ON2
, V
PRESDET
= 0 to 6V
1.4
-1
+1
0.4
V
V
FA
R
ON
15
24
41
mI
I
CB,TH
R
CB
= 28.57kI
R
CB
= 20kI
R
CB
= 10kI
t
SCD
0.6% overcurrent
30% overcurrent
6.3
4.5
3.15
1.575
7
5
3.5
1.75
2.7
200
7.7
5.5
3.85
1.925
ms
Fs
A
SYMBOL
V
IN
I
IN
V
UVLO
V
UVLO_HYS
V
ON1_TH
V
ON1_HYS
I
ON1
V
ON1
rising
V
ON1
falling
V
ON1
= 0 to 5V
-1
1.17
V
ON1
= 3V, no load, 7A current-limit
threshold
V
IN
rising, V
ON1
= V
IN
2.35
CONDITIONS
MIN
2.7
5
2.5
0.1
1.21
0.1
+1
1.25
TYP
MAX
18
7.5
2.65
UNITS
V
mA
V
V
V
V
FA
2.7V to 18V, 7A, Hot-Swap Solution
ELECTRICAL CHARACTERISTICS (continued)
(V
IN
= 12V, V
ON1
= 2V, V
ON2
= V
PRESDET
= 0V, R
CB
= 40kI, T
A
= T
J
= -40NC to +85NC, unless otherwise noted. Typical values are
at T
A
= +25NC.) (Note 3)
PARAMETER
OPEN-DRAIN OUTPUTS
FAULT,
PG Output Low Voltage
FAULT,
PG Output High
Leakage Current
OUT Bias Current
TIMING
Automatic Restart Delay After
Current-Limit Timeout
PG Assertion Delay
PG Threshold
THERMAL PROTECTION
Thermal-Shutdown Threshold
Thermal-Shutdown Threshold
Hysteresis
150
20
NC
NC
t
OFF
t
PG
V
PG
From V
OUT
> V
PG
V
OUT
= 12V
250
16
0.9 x
V
IN
ms
ms
V
V
OL
I
OH
I
OUT
Low-impedance state,
I
FAULT
= I
PG
= 5mA
High-impedance state,
V
FAULT
= V
PG
= 16V
V
ON1
= GND
0.4
1
10
V
FA
FA
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
MAX5976A/MAX5976B
Note 3:
All devices are 100% production tested at T
A
= +25°C. Limits over temperature are guaranteed by design.
Note 4:
The current-limit slow-comparator response time is weighed against the amount of overcurrent so that the higher the over-
current condition, the faster the response time.
Typical Operating Characteristics
(V
IN
= 12V, V
ON1
= 2V, R
CB
= 40kω, V
ON2
= V
PRESDET
= 0V, T
A
= +25°C, unless otherwise noted.)
SUPPLY CURRENT vs. TEMPERATURE
MAX5976 toc01
CIRCUIT-BREAKER THRESHOLD
vs. CIRCUIT-BREAKER RESISTANCE
MAX5976 toc02
CIRCUIT-BREAKER THRESHOLD
vs. TEMPERATURE
V
IN
= 12V
CIRCUIT-BREAKER THRESHOLD (A)
8
6
4
2
0
-40
-15
10
35
60
85
TEMPERATURE (°C)
R
CB
= 39.3kI
R
CB
= 30.1kI
R
CB
= 19.9kI
R
CB
= 10kI
MAX5976 toc03
6.0
V
ON1
= 2V
10
CIRCUIT-BREAKER THRESHOLD (A)
8
6
4
2
0
10
V
IN
= 12V
10
SUPPLY CURRENT (mA)
5.5
V
IN
= 12V
5.0
4.5
V
IN
= 5V
4.0
-40
-15
10
35
TEMPERATURE (°C)
60
85
V
IN
= 3V
15
20
25
R
CB
(kI)
30
35
40
3
2.7V to 18V, 7A, Hot-Swap Solution
MAX5976A/MAX5976B
Typical Operating Characteristics (continued)
(V
IN
= 12V, V
ON1
= 2V, R
CB
= 40kω, V
ON2
= V
PRESDET
= 0V, T
A
= +25°C, unless otherwise noted.)
ON-RESISTANCE vs. TEMPERATURE
MAX5976 toc04
TURN-ON WAVEFORM
MAX5976 toc05
NORMAL TURN-OFF WAVEFORM
MAX5976 toc06
40
V
IN
= 12V
I
LOAD
= 100mA
V
ON1
2V/div
0V
V
OUT
10V/div
V
PG
10V/div
I
LOAD
5A/div
0V
V
ON1
2V/div
ON-RESISTANCE (mI)
35
30
0V
0V
V
OUT
10V/div
V
PG
10V/div
I
LOAD
5A/div
25
0V
I
LOAD
= 5A
4ms/div
0V
I
LOAD
= 5A
4ms/div
20
-40
-15
10
35
TEMPERATURE (°C)
60
85
0A
0A
FAULT SHUTDOWN WAVEFORM—OVERLOAD
(SLOW TRIP)
MAX5976 toc07
FAULT SHUTDOWN WAVEFORM—SHORT
CIRCUIT
MAX5976 toc08
ON1 RISING/FALLING THRESHOLD VOLTAGE
vs. TEMPERATURE
V
OUT
10V/div
V
ON1
RISING/FALLING THRESHOLD VOLTAGE
1.22
1.20
1.18
1.16
1.14
1.12
1.10
-40
-15
10
35
60
85
TEMPERATURE (°C)
V
ON1
FALLING
V
ON1
RISING
MAX5976 toc09
1.24
V
OUT
10V/div
0V
I
LOAD
2A/div
0A
0V
V
PG
10V/div
V
FAULT
10V/div
2ms/div
0A
0V
0V
I
LOAD
10A/div
V
PG
10V/div
V
FAULT
10V/div
4ms/div
0V
0V
PG ASSERTION DELAY
MAX5976 toc10
AUTORETRY FUNCTIONALITY
MAX5976 toc11
CIRCUIT-BREAKER THRESHOLD TIME
vs. OVERCURRENT
V
OUT
500mV/div
3.0
2.8
2.6
2.4
2.2
2.0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
0
CIRCUIT-BREAKER THRESHOLD TIME (ms)
V
IN
= 12V
R
CB
= 19.9kI
MAX5976 toc12
V
ON1
1V/div
0V
V
OUT
5V/div
I
LOAD
= 7A
0V
I
LOAD
2A/div
0V
0V
0V
V
PG
5V/div
0V
4ms/div
40ms/div
V
FAULT
10V/div
500
1000
1500
2000
2500
3000
OVERCURRENT (%)
4
2.7V to 18V, 7A, Hot-Swap Solution
Pin Configuration
OUT
OUT
OUT
MAX5976A/MAX5976B
TOP VIEW
PRESDET
12
11
10
9
ON2 13
CB 14
REG 15
ON1 16
8
7
OUT
PG
FAULT
IN
MA5976A
MA5976B
+
1
GND
2
IN
3
IN
EP*
6
5
4
IN
TQFN
*CONNECT EP TO GND.
Pin Description
PIN
1
2–5
6
7
8–11
12
13
14
15
NAME
GND
IN
FAULT
PG
OUT
PRESDET
ON2
CB
REG
FUNCTION
Ground
Supply Voltage Input. IN is connected to the drain of the internal 24mI MOSFET. Bypass IN with
1FF capacitor to ground. Add a transient voltage suppressor diode from IN to GND for output
short-circuit protection.
Fault Status Output.
FAULT
is an open-drain, active-low output.
FAULT
asserts low when an over-
current or overtemperature condition triggers a shutdown.
Power-Good Output. PG is an open-drain, active-high output. PG pulls low until the internal power
MOSFET is fully enhanced.
Load Connection Point. Source of the internal power MOSFET.
Active-Low Present-Detect Logic Input. Pulling
PRESDET
to GND enables the output if
ON2
is low
and ON1 is high.
Active-Low Enable Logic Input. Pulling
ON2
to GND enables the output if
PRESDET
is low and
ON1 is high.
Current-Limit Threshold Set. Connect a resistor from CB to GND to set the circuit-breaker threshold.
Internal Regulator Output. Bypass to ground with a 1FF capacitor. Do not power external circuitry
using the REG output.
Active-High Enable Comparator Input. Pulling ON1 high enables the output if
PRESDET
and
ON2
are held low. ON1 also sets the undervoltage threshold. See the Setting
the Undervoltage
Threshold
section.
Exposed Pad. EP is internally grounded. Connect externally to ground plane for effective heat dis-
sipation. Do not use as the only ground connection.
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