SGM25711B [SGMICRO]
2.5V to 18V High-Efficiency Hot Swap Controller with Power-Limiting;
| 型号： | SGM25711B |
| 厂家： | 
Shengbang Microelectronics Co, Ltd |
| 描述： | 2.5V to 18V High-Efficiency Hot Swap Controller with Power-Limiting |
| 文件： | 总23页 (文件大小：2166K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
SGM25711B
2.5V to 18V High-Efficiency
Hot Swap Controller with Power-Limiting
GENERAL DESCRIPTION
FEATURES
The SGM25711B is a hot swap controller that allows a
board to be safely inserted or removed from a live
backplane. An internal circuit drives an external
N-MOSFET switch to control supply voltage from 2.5V
to 18V.
● Input Voltage Range from 2.5V to 18V
● Programmable MOSFET SOA Protection
● Accurate Current Limit at All Times
● Accurate 25mV Current Sense Threshold
● Power Good Output
● Fast Circuit-Breaker for Short-Circuit Protection
● Programmable Fault Timer
● Programmable Under-Voltage Threshold
● Active-Low for nPG and nFLT Pins
● Available in a Green MSOP-10 Package
The SGM25711B offers programmable current limit,
power-limiting and fault time to ensure that the external
MOSFET is always working within its safe operating
area. If the load current is higher than the set current for
more than the programmed time, the external MOSFET
will be shutdown. The SGM25711B restarts automatically
after a fault timeout delay. The low current sense
threshold of 25mV is very accurate, which allows the
use of smaller detection resistors resulting in lower
power losses and smaller size.
APPLICATIONS
Medical Systems
Storage Area Networks (SAN)
Plug-In Modules
This feature allows the user to easily design a high
reliability system. The device has power and fault
output functions to provide condition monitoring and
load protection.
Base Stations
SGM25711B is available in a Green MSOP-10 package.
TYPICAL APPLICATION
RSENSE
2mΩ
M1
VIN
CSD16403Q5
VOUT
COUT
C1
0.1μF
470μF
RGATE
10Ω
3V
SENSE
GATE
OUT
nPG
R4
3.01kΩ
VCC
R5
3.01kΩ
R1
130kΩ
SGM25711B
nFLT
EN
R2
18.7kΩ
TIMER
GND
PROG
CTIMER
56nF
RPROG
44.2kΩ
VUVLO = 10.8V
ILIM = 12A
tnFLT = 7.56ms
Figure 1. Typical Application Circuit (12V/10A)
SG Micro Corp
OCTOBER 2022 – REV. A. 1
www.sg-micro.com
2.5V to 18V High-Efficiency
SGM25711B
Hot Swap Controller with Power-Limiting
PACKAGE/ORDERING INFORMATION
SPECIFIED
TEMPERATURE
RANGE
PACKAGE
DESCRIPTION
ORDERING
NUMBER
PACKAGE
MARKING
PACKING
OPTION
MODEL
SGMRB7
XMS10
XXXXX
SGM25711B
MSOP-10
SGM25711BXMS10G/TR
Tape and Reel, 4000
-40℃ to +125℃
MARKING INFORMATION
NOTE: XXXXX = Date Code, Trace Code and Vendor Code.
X X X X X
Vendor Code
Trace Code
Date Code - Year
Green (RoHS & HSF): SG Micro Corp defines "Green" to mean Pb-Free (RoHS compatible) and free of halogen substances. If
you have additional comments or questions, please contact your SGMICRO representative directly.
OVERSTRESS CAUTION
ABSOLUTE MAXIMUM RATINGS
Input Voltage Range
Stresses beyond those listed in Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to
absolute maximum rating conditions for extended periods
may affect reliability. Functional operation of the device at any
conditions beyond those indicated in the Recommended
Operating Conditions section is not implied.
EN, nFLT (1), nPG (1), GATE, OUT, SENSE, VCC..............
.................................................................... -0.3V to 30V
PROG (1) ..................................................... -0.3V to 3.6V
SENSE to VCC............................................ -0.3V to 0.3V
TIMER ...........................................................-0.3V to 5V
Sinking Current
ESD SENSITIVITY CAUTION
nFLT, nPG ............................................................... 5mA
Sourcing Current
This integrated circuit can be damaged if ESD protections are
not considered carefully. SGMICRO recommends that all
integrated circuits be handled with appropriate precautions.
Failureto observe proper handling and installation procedures
can cause damage. ESD damage can range from subtle
performancedegradation tocomplete device failure. Precision
integrated circuits may be more susceptible to damage
because even small parametric changes could cause the
device not to meet the published specifications.
PROG.................................................... Internally limited
Package Thermal Resistance
MSOP-10, θJA ........................................................164℃/W
Junction Temperature ..............................................+150℃
Storage Temperature Range ......................-65℃ to +150℃
Lead Temperature (Soldering, 10s) ..........................+260℃
ESD Susceptibility
HBM......................................................................... 4000V
CDM......................................................................... 1000V
DISCLAIMER
SG Micro Corp reserves the right to make any change in
NOTE: 1. Do not apply voltage directly to the pin.
circuit design, or specifications without prior notice.
RECOMMENDED OPERATING CONDITIONS
Input Voltage Range
SENSE, VCC ................................................ 2.5V to 18V
EN, nFLT, nPG, OUT........................................ 0V to 18V
Sinking Current
nFLT, nPG ................................................... 0mA to 2mA
Resistance, RPROG......................................4.99kΩ to 500kΩ
External Capacitance, CTIMER................................1nF (MIN)
Operating Junction Temperature Range .....-40℃ to +125℃
SG Micro Corp
www.sg-micro.com
OCTOBER 2022
2
2.5V to 18V High-Efficiency
SGM25711B
Hot Swap Controller with Power-Limiting
PIN CONFIGURATION
(TOP VIEW)
nPG
EN
1
2
3
4
5
10 nFLT
9
8
7
6
VCC
PROG
TIMER
GND
SENSE
GATE
OUT
MSOP-10
PIN DESCRIPTION
PIN
NAME
FUNCTION
Power Good Indicator Pin (Active-Low, Open-Drain). The voltage of the external MOSFET
determines its state.
1
nPG
2
3
4
5
EN
Enable Pin. Active-high enable input. Connect to resistor divider.
Power-Limiting Programmable Pin. The power-limiting resistor connected to this pin determines
the maximum allowable dissipation of the external MOSFET.
PROG
TIMER
GND
Fault Timer Pin. An external capacitor on this pin sets the insertion delay time and fault time
delay. The chip's restart time is also controlled by this capacitor.
Ground.
Power Output Pin. Connect this pin to output (i.e., external MOSFET source). The chip monitors
MOSFET VDS voltage through this pin to limit the MOSFET power and control the nPG signal
accordingly.
6
OUT
7
8
GATE
SENSE
VCC
Gate Driver Output. This pin is connected to the gate of the external MOSFET.
Current Sense Pin. The voltage from the input pin to this pin is measured by the current flowing
into the sense resistor.
9
Power Input Pin. It is recommended to place a small bypass capacitor close this pin.
Fault Event Indicator Pin. Go low when the external MOSFET has been turned off by the
overload fault timer.
10
nFLT
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2.5V to 18V High-Efficiency
SGM25711B
Hot Swap Controller with Power-Limiting
ELECTRICAL CHARACTERISTICS
(-40℃ ≤ TJ ≤ +125℃, VCC = 12V, VEN = 3V and RPROG = 50kΩ to GND. Typical values are at TJ = +25℃, unless otherwise noted.)
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
VCC
UVLO Threshold Voltage, Rising
UVLO Threshold Voltage, Falling
Hysteresis
2.25
2.17
2.35
2.27
85
2.45
2.37
V
V
mV
mA
μA
Supply Current, Enabled
Supply Current, Disabled
EN
IOUT + IVCC + ISENSE
VEN = 0V, IOUT + IVCC + ISENSE
0.32
4
0.5
Enable Threshold Voltage, Falling
Hysteresis
1.25
-1
1.3
55
0
1.35
1
V
mV
µA
Input Leakage Current
nFLT
VEN = 0V to 30V
Output Low Voltage
Input Leakage Current
nPG
Sinking 2mA
35
0
65
1
mV
µA
VnFLT = 0V or 30V
-1
nPG Threshold Voltage
Hysteresis
V(SENSE - OUT) rising, nPG going high
V(SENSE - OUT) falling, nPG going low
Sinking 2mA
235
315
85
35
0
395
mV
mV
mV
µA
Output Low Voltage
Input Leakage Current
PROG
65
1
VnPG = 0V or 30V
-1
Bias Voltage
Sourcing 10µA
VPROG = 1.5V
0.65
-0.2
0.68
0
0.71
0.2
V
Input Leakage Current
TIMER
µA
Sourcing Current
VTIMER = 0V
8
8
10
10
12
12
µA
µA
mA
V
VTIMER = 2V
Sinking Current
VEN = 0V, VTIMER = 2V
4.5
1.3
0.33
7
9.5
1.4
0.38
TIMER Threshold Voltage, Rising
TIMER Threshold Voltage, Falling
1.35
0.35
V
Raise GATE until ITIMER sinking, measure V(GATE - VCC)
VCC = 12V
,
Timer Activation Voltage
5.3
5.6
5.9
V
OUT
Input Bias Current
GATE
VOUT = 12V
1
µA
Output Voltage
Clamp Voltage
Sourcing Current
VOUT = 12V
24.5
12
25.5
13.5
33
26.5
15
V
V
Inject 10μA into GATE, measure V(GATE - VCC)
VGATE = 12V
20
46
μA
mA
mA
kΩ
Fast turn-off, VGATE = 0.2V
Sustained, VGATE = 4V to 23V
Thermal shutdown
33
63
93
Sinking Current
6
11
16
Pull-Down Resistance
SENSE
11.5
17.5
23.5
Input Bias Current
VSENSE = 12V, sinking current
15
25
25
27
µA
23
V
OUT = 12V, -20℃ ≤ TJ ≤ +125℃
Current Limit Threshold
mV
22.5
25
27.5
VOUT = 12V, -40℃ ≤ TJ ≤ +125℃
VOUT = 7V, RPROG = 50kΩ
VOUT = 2V, RPROG = 25kΩ
10
10
14
14
18
18
Power-Limiting Threshold
mV
mV
Fast-Trip Shutdown Threshold
52.3
61.5
70.7
Over-Temperature Shutdown (OTSD)
Threshold, Rising
145
15
℃
℃
Hysteresis
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2.5V to 18V High-Efficiency
SGM25711B
Hot Swap Controller with Power-Limiting
TIMING REQUIREMENTS
PARAMETER
EN
CONDITIONS
MIN
TYP
MAX
UNITS
Deglitch Time
EN↑
10
39.5
80
1
µs
µs
Disable Delay Time (tpff50-90
nPG
)
EN↓ to GATE↓, CGATE = 0, see Figure 2
0.33
0.665
Delay (Deglitch) Time
GATE
Rising or falling edge
2
9
4
6
ms
Fast Turn-Off Duration
13.5
125
18
µs
µs
Turn-On Delay Time (tprr50-50
SENSE
)
VCC rising to GATE sourcing, see Figure 3
250
Fast Turn-Off Duration
9
13.5
250
18
µs
ns
Fast Turn-Off Delay Time (tprf50-50
)
V(VCC - SENSE) = 80mV, CGATE = 0pF, see Figure 4
90%
IGATE
50%
VGATE
tpff50-90
VCC
50%
50%
tprr50-50
VEN
Figure 2. tpff50-90 Timing Waveform
Figure 3. tprr50-50 Timing Waveform
VGATE
50%
50%
V(VCC
–
SENSE)
tprf50-50
Figure 4. tprf50-50 Timing Waveform
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2.5V to 18V High-Efficiency
SGM25711B
Hot Swap Controller with Power-Limiting
TYPICAL PERFORMANCE CHARACTERISTICS
Supply Current vs. Input Voltage at Normal Operation
EN = High
Supply Current vs. Input Voltage at Shutdown
EN = Low
450
400
350
300
250
200
150
7
6
5
4
3
2
1
TJ = -40℃
TJ = +25℃
TJ = +125℃
TJ = -40℃
TJ = +25℃
TJ = +125℃
2
4
6
8
10
12
14
16
18
2
4
6
8
10
12
14
16
18
Input Voltage (V)
Input Voltage (V)
Voltage Across RSENSE in Inrush Power-Limiting vs. VDS of Pass
Voltage Across RSENSE in Inrush Current Limit vs. Temperature
26.5
MOSFET
32
VCC = 12V
26.0
25.5
25.0
24.5
27
22
17
12
VCC = 2.5V
VCC = 12V
VCC = 18V
TJ = -40℃
24.0
7
TJ = +25℃
TJ = +125℃
23.5
2
-50 -25
0
25
50
75 100 125 150
0
2
4
6
8
10
12
14
Temperature (℃)
VDS of Pass MOSFET (V)
Gate Current vs. Voltage Across RSENSE
Gate Current vs. Voltage Across RSENSE
40
0
40
0
TJ = -40℃
TJ = +25℃
TJ = +125℃
TJ = -40℃
TJ = +25℃
TJ = +125℃
-40
-40
-80
-80
-120
-160
-200
-120
-160
-200
VCC = 12V
VOUT = 0V
RPROG = 50kΩ
VCC = VOUT = 12V
Gate Current at Current Limit
VGATE = 3V
1
2
3
4
5
6
7
8
9
10
0
7
14 21 28
35
42
49
56
Voltage Across RSENSE (mV)
Voltage Across RSENSE (mV)
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2.5V to 18V High-Efficiency
SGM25711B
Hot Swap Controller with Power-Limiting
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
Gate Voltage with Zero Gate Current vs. Input Voltage
32
Gate Current during Fast-Trip
70
60
50
40
30
20
10
0
4
3
28
24
20
16
12
8
2
1
V(VCC - SENSE)
0
-1
-2
-3
-4
VCC = 6V
VGATE = 0.2V
TJ = -40℃
TJ = +25℃
TJ = +125℃
TJ = -40℃
TJ = +25℃
TJ = +125℃
-10
2
4
6
8
10
12
14
16
18
0
15
30
45
60
75
90 105 120
Input Voltage (V)
Time (μs)
EN Threshold Voltage vs. Temperature
VCC = 12V
UVLO Threshold Voltage vs. Temperature
VCC = 12V
2.4
2
2.44
2.40
2.36
2.32
2.28
2.24
2.20
UVLO Threshold Rising
1.6
1.2
0.8
0.4
0
EN Threshold Rising
UVLO Threshold Falling
-50 -25
0
25
50
75 100 125 150
-50 -25
0
25
50
75 100 125 150
Temperature (℃)
Temperature (℃)
Threshold Voltage of VDS vs. Temperature
Fast-Trip Shutdown Threshold Voltage vs. Temperature
62.5
360
330
300
270
240
210
180
62.0
61.5
61.0
60.5
60.0
59.5
nPG Rising
VCC = 2.5V
VCC = 12V
VCC = 18V
nPG Falling
-50 -25
0
25
50
75 100 125 150
-50 -25
0
25
50
75 100 125 150
Temperature (℃)
Temperature (℃)
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2.5V to 18V High-Efficiency
SGM25711B
Hot Swap Controller with Power-Limiting
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
nPG Open-Drain Output Voltage in Low-State vs. Temperature
70
nFLT Open-Drain Output Voltage in Low-State vs. Temperature
70
60
50
40
30
20
10
60
50
40
30
VCC = 2.5V
VCC = 12V
VCC = 2.5V
VCC = 12V
VCC = 18V
20
VCC = 18V
10
-50 -25
0
25
50
75 100 125 150
-50 -25
0
25
50
75 100 125 150
Temperature (℃)
Temperature (℃)
Timer Upper Threshold Voltage vs. Temperature
Timer Lower Threshold Voltage vs. Temperature
1.357
1.355
1.353
1.351
1.349
1.347
1.345
0.357
0.356
0.355
0.354
0.353
0.352
0.351
VCC = 2.5V
VCC = 12V
VCC = 18V
VCC = 2.5V
VCC = 12V
VCC = 18V
-50 -25
0
25
50
75 100 125 150
-50 -25
0
25
50
75 100 125 150
Temperature (℃)
Temperature (℃)
Timer Sourcing Current vs. Temperature
Timer Sinking Current vs. Temperature
10.4
10.3
10.2
10.1
10
10.4
10.3
10.2
10.1
10
9.9
VCC = 2.5V
VCC = 12V
VCC = 18V
VCC = 2.5V
VCC = 12V
VCC = 18V
9.9
9.8
9.7
9.8
-50 -25
0
25
50
75 100 125 150
-50 -25
0
25
50
75 100 125 150
Temperature (℃)
Temperature (℃)
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2.5V to 18V High-Efficiency
SGM25711B
Hot Swap Controller with Power-Limiting
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
Fault Timer Period vs. Temperature
VCC = 12V
Timer Activation Voltage vs. Input Voltage
3
2.5
2
9
8
7
6
5
4
3
CTIMER = 10nF
1.5
1
CTIMER = 4.7nF
CTIMER = 1nF
TJ = -40℃
TJ = +25℃
TJ = +125℃
0.5
0
-50 -25
0
25
50
75 100 125 150
2
4
6
8
10
12
14
16
18
Temperature (℃)
Input Voltage (V)
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2.5V to 18V High-Efficiency
SGM25711B
Hot Swap Controller with Power-Limiting
FUNCTIONAL BLOCK DIAGRAM
M1
VIN
RSENSE
RGATE
GATE
VCC
SENSE
OUT
9
8
7
6
Charge
Pump
33μA
SENSE
VDS
Sample
+
-
DC
5.6V
PG
Gate
Comparator
Comparator
DC
-
+
Current
Sense OPA
+
-
DC
61.5mV
315mV
230mV
Fast
Comparator
4ms
UVLO
+
-
11mA
2.35V
2.27V
GATE Control
+
-
1
nPG
POR
&
Logic
1.5V
680mV
+
-
PROG
3
10μA
10 nFLT
607mV
RPROG
+
+
-
-
10μA
RLIMIT
1.35V
0.35V
+
-
2
EN
1.35V
1.3V
OTSD
39.5μs
4
5
GND
TIMER
CTIMER
Figure 5. Block Diagram
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2.5V to 18V High-Efficiency
SGM25711B
Hot Swap Controller with Power-Limiting
DETAILED DESCRIPTION
the chip trips shutdown quickly, and there is still 11mA
pull-down current to turn off the MOSFET.
VCC
There are three functions for the VCC pin. First, power
the chip. Second, this pin is the input terminal of power
on reset (POR) and under-voltage lockout (UVLO)
functions. Third, the lead of the VCC should be directly
connected to the positive end of the sense resistor, so
that the current flowing through the resistor can be
more accurately detected. A 0.1μF capacitor is
recommended.
3. If the chip temperature exceeds the threshold, the
chip discharges the GATE charge to GND through a
17.5kΩ resistor. In the auto-retry mode, the chip will
restart periodically. No resistance should be connected
between the GATE and GND (or OUT) pins.
nFLT
The nFLT pin is assigned for SGM25711B. When the
SGM25711B remains within the current limit long
enough for the fault timer to expire, the low open-drain
output will be pulled low. The SGM25711B operates in
auto-retry mode. In the auto-retry mode, the fault
timeout will stop the operation of the external MOSFET
(M1) and try to restart after 16 hiccup cycles. When the
fault is not eliminated, the hiccup continues. At this time,
this pin will be pulled low. If M1 is disabled by EN,
OTSD or UVLO, the nFLT pin will not be asserted. The
pin can remain suspended when not needed.
EN
When the voltage of EN pin is greater than 1.35V, the
gate driver starts to work. An external divide resistor
can be added to monitor the input under-voltage. When
the chip is locked, pull down and then up EN to restart
the chip. Do not float this pin.
GATE
This pin is the MOSFET (M1) gate drive. The charge
pump charges the gate with a current of 33µA. Since
VCC is approximately equal to VOUT during normal
operation, the V(GATE - VCC) is clamped to a maximum of
OUT
13.5V. During startup, the amplifier regulates the output
current to control the gate voltage and to limit the inrush
current. During the surge, the TIMER pin charges the
This pin can measure the voltage between drain and
source of MOSFET. Power-limiting also needs the
function of this pin. It is recommended to place
Schottky diode to prevent negative pressure. At the
same time, this pin needs to connect the low ESR
ceramic capacitor to the ground to bypass the
high-frequency signal.
capacitor with a current of 10µA until the V(GATE
voltage exceeds the set voltage (5.6V when VCC = 12V),
if V(GATE VCC) is greater than the timer set voltage, the
TIMER pin stops sourcing current and starts sinking
current. This pin is disabled in three situations:
-
VCC)
-
nPG
1. Under the following circumstances, the 11mA current
sink will pull down the GATE voltage:
When the voltage across drain and source of MOSFET
is less than 230mV and a deglitch time of 4ms elapses,
the drain of this pin is pulled down. When VDS > 315mV,
it becomes open-drain output. That is, when the VDS of
M1 rises, the pin assumes a high resistance state after
the same deglitch time.
V(VCC - SENSE) > 25mV.
VEN is lower than the falling threshold voltage.
VCC reaches the lower threshold of UVLO.
2. The GATE pin is pulled down through a 3.2Ω resistor
when VEN is less than its falling threshold or when an
output short occurs and V(VCC - SENSE) exceeds 61.5mV,
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2.5V to 18V High-Efficiency
SGM25711B
Hot Swap Controller with Power-Limiting
DETAILED DESCRIPTION (continued)
TIMER
PROG
A CTIMER capacitor is connected between TIMER and
GND to time the fault time. When the overload occurs,
the TIMER charges the CTIMER with 10μA current,
otherwise discharges the CTIMER with 10μA current. If
VTIMER reaches 1.35V, the MOSFET will be turned off.
The capacitor sets the restart time after failure. It is
recommended to place a minimum capacitance of 1nF
to ensure the normal operation of the timer. The value
of this capacitor can be calculated by the following
formula.
The resistance between PROG and GND pins sets the
maximum power allowed by MOSFET. Do not apply
voltage directly to the PROG pin. When the constant
power-limiting function is not used, connect this pin to
the ground with a 4.99kΩ resistance. If it is necessary
to set the constant power, please refer to Equation 1.
3600
RPROG
=
(1)
PLIM ×RSENSE
3600
RPROG ×RSENSE
P
=
(2)
LIM
10μA
1.35V
CTIMER
=
× tnFLT
(5)
where PLIM is the power-limiting value of the M1, RSENSE
is the detection resistor between VCC and SENSE pins,
and PLIM can calculate the maximum thermal stress of
If the load current is higher than the current setting
value or a fast-trip shutdown occurs, the MOSFET will
be stopped for 16 charging and discharging cycles.
After the time counting, the TIMER pin will be pulled to
GND by the 7mA sinking current, and then the
MOSFET will be restarted. In any of the following cases,
the CTIMER charge will also be put to GND by the 7mA
current source:
M1.
TJ(MAX) − TC(MAX)
(3)
P
<
LIM
RθJC(MAX)
where TJ(MAX) is the expected maximum junction
temperature, TC(MAX) is the maximum shell temperature,
and RθJC (MAX) is the junction shell thermal resistance.
VEN is less than the lower threshold.
VCC is less than the lower threshold of UVLO.
SENSE
This pin is the other end of the sense resistor. The
current can be limited by detecting the voltage across
sense resistor, refer to Equation 4.
25mV
ILIM
<
(4)
RSENSE
when V(VCC - SENSE) > 61.5mV, fast-trip shutdown occurs.
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2.5V to 18V High-Efficiency
SGM25711B
Hot Swap Controller with Power-Limiting
DETAILED DESCRIPTION (continued)
Inrush Operation
After the enable of SGM25711B is activated, the GATE
pin starts to flow current and the VGATE rises. When it
reaches the opening threshold of M1, M1 has current
flowing into the output capacitor. When the current is
higher than the limit value, the negative feedback
system will adjust the turn-on degree of the MOSFET to
keep the current at the limit value. Constant power
process is a more complex process. When the constant
power occurs, the TIMER pin starts charging the CTIMER
with a current of 10μA until V(GATE - VCC) = 5.6V. Then
discharge CTIMER with 10μA. When V(GATE - VCC) < 5.6V,
VTIMER exceeds the upper limit value of 1.35V, the
GATE is pulled down, and the chip enters the auto-retry
process.
Device Functional Modes
SGM25711B has all the functions of the forward hot
plug controller, mainly including: start surge
suppression, under-voltage lockout, external MOSFET
driving and power-limiting, overload timeout shutdown
and indication functions.
Figure 6 to Figure 8 and Figure 10 to Figure 12
respectively show the typical application (12V/10A) and
oscilloscope plots. Many of the previously described
capabilities are shown in these figures.
Board Plug-In
Figure 6 and Figure 7 show the surge current of
SGM25711B during hot plug. When VCC > 1.5V, power
on reset (POR) initializes and the chip is ready to start.
When the surge ends, the power-limiting function will
be disabled. When the load current is higher than the
limit value, the chip will turn off the MOSFET after the
timing period.
If the internal voltage is higher than the EN threshold,
GATE, PROG, TIMER, nPG, nFLT begin to release.
The chip starts to drive the MOSFET (M1) through the
GATE pin. At the same time, monitor the current and
voltage at both ends (DS) of M1 to limit the current and
power. The current increases with the decrease of VDS
until the current limit value is reached.
IIN
VGATE
VOUT
VTIMER
Time (2ms/div)
Figure 6. Inrush Mode at Hot Swap Circuit Insertion
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2.5V to 18V High-Efficiency
SGM25711B
Hot Swap Controller with Power-Limiting
DETAILED DESCRIPTION (continued)
The Action of a Constant Power Engine
Figure 7 shows the operation of constant power
function. After the PROG is connected to a resistor, it is
used to program the power-limiting of 54W. At this time,
the current starts to flow through the MOSFET. When
the VDS of MOSFET is 12V, the maximum allowable
current is 4.5A (54W divided by 12V). As the VDS
voltage decreases, the current will gradually increase.
Figure 7 shows the measured power of MOSFET. The
power remains essentially constant during operation
until the current limit is reached. The constant power
function allows the MOSFET to work close to its SOA
area, thereby reducing the constant power time and the
size of the MOSFET.
Figure 8 shows the performance of the chip when the
load current is higher than the current limit but below
the fast-trip shutdown threshold. When this happens,
the controller adjusts the gate voltage to adjust the
current flowing through RSENSE to the set current. At the
same time, the CTIMER is charged with a 10μA current
source. When the VTIMER reaches the upper limit of
1.35V, the MOSFET is turned off, and the chip is
restarted cyclically. At the same time, the nFLT pin is
pulled down to indicate a fault.
Figure 10 and Figure 11 show the behavior when a fast-
trip shutdown occurs. The function of fast-trip shutdown
is to prevent the system from being cut off quickly in
case of serious failure. When the RSENSE voltage
exceeds the fast-trip shutdown threshold, the gate
charge is immediately pulled down to GND by the large
current source, and the resistance is about 3.2Ω at this
time. The turn-off current can be changed by a low
value resistance connected in series between GATE
pin and gate of the MOSFET. After a few milliseconds
of fast-trip, the gate voltage rises again and the circuit
restarts.
VDS
VTIMER
IIN
VGATE
FET
PWR
VGATE
VnFLG
Time (1ms/div)
Figure 7. Computation of M1 Power Stress during Startup
IIN
Circuit-Breaker and Fast-Trip
By monitoring the voltage across RSENSE
,
the
VTIMER
SGM25711B measures load current. The SGM25711B
offers two limit thresholds: a current limit threshold and
a fast-trip shutdown threshold.
Time (2ms/div)
The circuit-breaker mode and fast-trip turn-off are
shown in Figure 8 through Figure 11.
Figure 8. Circuit-Breaker Mode during Overload
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2.5V to 18V High-Efficiency
SGM25711B
Hot Swap Controller with Power-Limiting
DETAILED DESCRIPTION (continued)
M1
VIN
RSENSE
RGATE
GATE
VCC
SENSE
OUT
9
8
7
6
Charge
Pump
33μA
SENSE
VDS
Sample
+
-
DC
5.6V
Gate
Comparator
DC
-
+
Current
Sense OPA
+
-
DC
61.5mV
315mV
230mV
PG
Comparator
Fast
Comparator
UVLO
+
11mA
2.35V
2.27V
-
GATE Control
&
Logic
+
-
POR
4ms
1.5V
680mV
+
-
607mV
+
-
PROG
3
RPROG
RLIMIT
Figure 9. Partial Diagram of the SGM25711B with Selected External Components
Auto-Retry
SGM25711B will turn off the MOSFET and restart
automatically when a fault occurs. Restart the MOSFET
after 16 timing cycles, as shown in Figure 12. When the
fault still exists, the timing and restart will continue. At
this time, the charging and discharging currents are the
same. In the first cycle, the TIMER voltage rises from
0V to 1.35V and then drops to 0.35V. For the next 16
counting cycles, 0.35V is used as low threshold cycle.
This will reduce the thermal stress caused to MOSFET
restarting.
VGATE
VTIMER
IIN
VOUT
Time (2ms/div)
Figure 10. Current Limit during Output Short-Circuit
(Overview)
VnFLG
VGATE
VGATE
IIN
IIN
VTIMER
VTIMER
VOUT
Time (50ms/div)
Figure 12. Auto-Retry Cycle Timing
Time (10μs/div)
Figure 11. Current Limit during Output Short-Circuit
(Onset)
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SGM25711B
Hot Swap Controller with Power-Limiting
DETAILED DESCRIPTION (continued)
During the restart period, CTIMER's 16th discharge until
VTIMER is pulled down to 0V, after the GATE pin briefly
opens for the first half-cycle of the charge. This cyclical
process continues until the failure is recovered or the
device is disabled by EN or UVLO.
nPG, nFLT and TIMER Operations
The nPG adds the deglitched design inside, which
changes to active-low after COUT is fully charged for
4ms, providing sufficient margin for various unstable
situations at power-up.
Make sure that the chosen MOSFET on-resistance is
as small as possible, and in order for the system to
operate in a safe temperature or electrical environment,
the nPG will change to a high-impedance state when
the on-voltage drop of the MOSFET is greater than
315mV to send a warning to the downstream device.
Over-Temperature Shutdown (OTSD)
Over-temperature protection circuitry has also been
added inside the device, and when the temperature
exceeds +145℃, the MOSFET will be turned off and
the nFLT, nPG pins will enter into high-impedance state.
The recovered temperature hysteresis is 15℃.
When the over-current condition occurs, an internal
10μA current source charges the CTIMER and starts fault
timing, and when the voltage of the CTIMER reaches
1.35V, the nFLT pin is pulled low, otherwise the high-
impedance state continues.
Startup of Hot Swap Circuit by VCC or EN
When EN or UVLO reaches the upper threshold, the
device charges the GATE pin, and after the inrush
process, M1 is fully turned on.
The fault timer starts counting at any of the following
moments:
M1 will be shut down when EN under-voltage, load
over-current, short-circuit, or over-temperature occurs.
1. During start-up, if V(GATE - VCC) rises to the voltage of
timer activation before VTIMER reaches 1.35V, the device
assumes that the MOSFET can start normally, the fault
timer will shut down. If the V(GATE - VCC) is less than the
voltage of timer activation within the fault time set by
the CTIMER, the MOSFET will be shut down and enter an
auto-retry.
1. If the following happens, the GATE is pulled low by
an 11mA current source.
The fault timer expires during an overload current
fault (V(VCC - SENSE) > 25mV).
The value of VEN is less than the falling threshold
voltage.
The value of VCC is lower than the UVLO
threshold.
2. When the over-current condition occurs, the CTIMER is
charged from 0V to 1.35V starting with the GATE pin
which is pulled low. After fault timer period, the TIMER
will enter the auto-retry mode.
2. When the output hard short occurs and the V(VCC -
is higher than the fast-trip shutdown threshold
SENSE)
(61.5mV), the GATE is pulled down through an
N-MOSFET (3.2Ω when VDS = 0.2V) by 13.5μs. After
the fast-trip shutdown is complete, a continuous current
of 11mA ensures that the external MOSFET remains
shutdown.
3. After an output short-circuit causes an over-current,
the MOSFET is quickly shut down. The CTIMER is
charged from 0V to 1.35V starting the GATE pin which
is pulled low. After fault timer period, the TIMER will
enter the auto-retry mode.
3. If the die temperature is higher than the OTSD rising
threshold, GATE pin is discharged to GND by a 17.5kΩ
resistor.
If the load returns below the programmed current limit
value during the restart period, the MOSFET turns on
after the VTIMER drops to 0V.
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2.5V to 18V High-Efficiency
SGM25711B
Hot Swap Controller with Power-Limiting
APPLICATION INFORMATION
SGM25711B is a hot swap controller used to limit
inrush current and protect loads device. Please take
special care of below factors before designing.
Power-Limiting Startup
This application example assumes 12V system power
supply with the swinging range of ±2V, 10A stable
output current with over-current limit value of 12A with
the +20℃ to +50℃ operating temperature range. A
470μF output capacitor is set. Please refer to Figure 14
for more details.
Startup.
Output shorted to ground when hot swap controller
is on.
Start-into-shorted.
SOA of MOSFET.
Take all factors and conditions of M1 such as the
operating temperature, package, RDSON, fault timeout,
current limit and power-limiting into consideration. The
design procedure is intend to keep the MOSFET
operating in safe area and restart in time after power-
limiting. Please adapt this design procedure to fit the
application.
Typical Application
Please refer to the detailed design procedure of this
section as a calculating example. Related parameters
are shown in the following table.
RSENSE
2mΩ
M1
VIN
CSD16403Q5
VOUT
COUT
RSENSE
M1
Load
C1
0.1μF
470μF
RGATE
10Ω
RGATE
3V
COUT
470μF
SENSE
GATE
SENSE
GATE
GND
OUT
nPG
R4
3.01kΩ
VCC
EN
R5
3.01kΩ
OUT
VCC
12V Main
Bus Supply
0.1μF
0.1μF
RLOAD
1.2Ω
R1
130kΩ
SGM25711B
SGM25711B
nFLT
R2
18.7kΩ
TIMER
GND
PROG
TIMER
CTIMER
CTIMER
56nF
RPROG
44.2kΩ
VUVLO = 10.8V
ILIM = 12A
tnFLT = 7.56ms
Specifications (at Output): Peak Current Limit: 12A, Nominal Current: 10A.
Figure 13. Typical Application (12V at 10A)
Figure 14. Simplified Block Diagram of the System
Constructed
Design Requirements
Table 1 lists the necessary parameters which are
needed to know before designing.
Table 1. Design Parameters
Parameter
Input Voltage
Value
12V ± 2V
10A
Operating Load Current (MAX)
Operating Temperature
Fault Trip Current
+20℃ to +50℃
12A
Load Capacitance
470µF
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2.5V to 18V High-Efficiency
SGM25711B
Hot Swap Controller with Power-Limiting
APPLICATION INFORMATION (continued)
Choose RSENSE
Choose PLIM and RPROG
The current limit voltage threshold is about 25mV
according to the electrical characteristics table. Choose
a resistance of 2mΩ to realize the peak current limit of
12A. Please take care of the power loss of the
resistance and choose suitable specifications.
The M1 consumes large power during start-up. Please
avoid the device rising temperature to an absolute
maximum value (TJ(MAX)2) for a short period of time.
Assuming the value is 130℃, refer to the Equation 8 to
calculate the minimum PLIM
.
TJ(MAX)2
−
I
2 ×RDSON ×RθCA + T
V
(VCC - SENSE)
(
)
MAX A(MAX)
RSENSE
=
P
≤ 0.8×
LIM
ILIM
RθJC
therefore,
therefore,
25mV
12A
2
130℃ − 12A ×0.002Ω×（51℃/W-1.8℃/W + 50℃
(
)
(6)
RSENSE
=
≈ 2mΩ
P
≤ 0.8×
= 29.3W
LIM
1.8℃/W
(8)
Choose M1
The SGM25711B is designed for MOSFET with a
gate-source voltage rating of 20V.
If the operating temperature is 50℃, the PLIM (MAX) is
29.3W. Using Equation 2, RPROG chooses a 61.4kΩ, 1%
resistor (see Equation 9).
3600
Lower gate-source voltage MOSFET can be used with
an external Zener diode to keep the peak value of
gate-source voltage in absolute ratings.
RPROG
=
PLIM ×RSENSE
therefore,
3600
29.3W ×0.002Ω
Another factor must be considered is drain-to-source
voltage. So it is recommended that add an external
TVS to the input end. Extreme conditions of abrupt
shutoff or short-circuit will cause the surge in input
voltage. Besides, please use MOSFET with the VDS(MAX)
rating at least twice as the power supply value.
RPROG
=
= 61.4kΩ
(9)
Choose Output Voltage Rise Time (tON), CTIMER
Please make sure the load capacitance is fully charged
before the timing period set by timer capacitor stops.
So that the system will not trigger the fault circuit.
Please refer to Equation 10 for more details.
Voltage across the MOSFET should less than minimum
nPG threshold of 235mV. A maximum on-resistance of
19mΩ is required under the condition of 12A current
limit. Besides, please refer to Equation 7 to calculate
the maximum on-resistance at the corresponding
ambient temperature.
Assuming that there is no resistive load at the startup
time.
2
COUT × VCC(MAX)
COUT × VCC(MAX)
COUT ×P
2×ILIM
LIM
2
+
−
if P < ILIM × VCC(MAX)
LIM
2×P
ILIM
LIM
tON
=
COUT × VCC(MAX)
TJ(MAX) − TA(MAX)
IMAX2 ×RθJA
if P > ILIM × VCC(MAX)
LIM
ILIM
RDSON(MAX)
=
therefore,
470μF× 29.3W 470μF×(12V)2 470μF×12V
therefore,
tON
=
+
−
= 0.73ms
2×(12A)2
2× 29.3W
12A
150℃ - 50℃
RDSON(MAX)
=
= 13.6mΩ
(7)
(12A)2 ×51℃/W
(10)
Considering all these factors, choose CSD16403Q5 as
the switch device for the example. This transistor has a
VGS(MAX) rating of 16V, a VDS(MAX) rating of 25V, and a
maximum RDSON of 2.8mΩ at room temperature. The
device can hold up to 10A current flowing through
during normal operation. The power dissipation of the
MOSFET is about 0.24W and a 9.6℃ rise in junction
temperature.
Power dissipation of the MOSFET must be kept in SOA
as the power consumption during a fault is much larger
than it in steady-state.
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2.5V to 18V High-Efficiency
SGM25711B
Hot Swap Controller with Power-Limiting
APPLICATION INFORMATION (continued)
The tON calculated in Equation 10 only takes the voltage
rise in OUT capacitor into consideration. Besides, when
consider the time margin set by the timing capacitor,
add up the time which takes to charge the GATE pin
voltage to 5.6V above the input voltage. Please refer to
the Equation 11.
If R1 is 130kΩ, the value of R2 can be calculated as
18.7kΩ.
Select R4, R5, RGAT E and C1
Choose the appropriate gate resistor based on the
actual input capacitance value of MOSFET, and if the
CISS of the MOSFET is less than 200pF, a gate
resistance of 33Ω is recommended. In addition, if
required, assign 3.3kΩ pull-up resistors to the nFLT and
nPG pins, as they are open-drain outputs. C1 is a
bypass capacitor and ceramic capacitors which are
smaller than 100nF are recommended.
5.6V ×CISS
tnFLT = tON
+
IGATE
therefore,
5.6V × 2040pF
20μA
(11)
tnFLT = 0.73ms +
= 1.3ms
It should learn about the IGATE is 20μA and CISS is
2040pF through respective electrical characteristic. By
using the example parameters, it is easy to get that the
CSD16403Q5 takes 1.3ms as the fault time. Please
also kindly refer to the SOA curves of MOSFET for
circuit safety. The fault timer should be set higher than
1.3ms to avoid power loss during startup and below the
corresponding time of the SOA curve at the specified
operating temperature.
Use of nPG
To avoid undesired latch-up of the downstream DC/DC
converter, please use nPG to control the enable pin of
the DC/DC converter instead of connect the COUT of the
hot swap controller to the VIN pin of the downstream
device directly. It also can use a long time delay to
make sure the fully charge of the COUT
.
Factors such as temperature, component tolerance and
load characteristics, choose 7ms as the fault time to
reserve sufficient margin. Choose the second highest
capacitor specification is 52nF and the final failure time
is 7.56ms.
Output Clamp Diode
To avoid inverting condition of the OUT pin caused by
inductive loads transients or current limit, please
connect a Schottky diode to the OUT end.
10μA
Gate Clamp Diode
CTIMER
=
× tnFLT
1.35V
To keep the VGS of M1 in absolute rating, connect an
external clamp Zener to the gate and source of the M1 if
it is needed. Please also connect a series resistance or
a silicon diode to cut off the output capacitance
discharging path through GATE pin.
therefore,
10μA
(12)
CTIMER
=
×7ms = 52nF
1.35V
Calculate the Auto-Retry Mode Duty Ratio
Learn about the device will be charged and discharged
16 times as Figure 12. Note that the timer capacitor will
charge from 0V to 1.35V and discharge from 1.35V to
0.35V. So, the total time is 7.56ms + 33 × 5.6ms =
192.36ms. The auto-retry mode duty cycle is
7.56ms/192.36ms = 3.93%.
High Gate Capacitance Applications
Once the gate capacitance (total) of the MOSFET is
larger than 4000pF, use an external Zener diode to gate
voltage overstress or fault current spikes.
Bypass Capacitors
To avoid large inrush current during plug-in period,
please use suitable low-impedance ceramic capacitor
(10nF to 0.1μF is recommended).
Select the R1 and R2 for Under-Voltage
Next, select the value of the divider resistance of the
UVLO pin as Figure 1 according to the VENTH value of
1.35V in electrical specifications.
R2
(13)
VENTH
=
× VCC
R1 + R2
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2.5V to 18V High-Efficiency
SGM25711B
Hot Swap Controller with Power-Limiting
APPLICATION INFORMATION (continued)
Using Soft-Start with SGM25711B
It can connect a capacitor from GATE to GND if the
constant output slew rate of the hot swap controller is
needed. The ramp rate of the GATE pin voltage is also
reflected at the output.
Power Supply Recommendations
Use a 10nF to 1μF ceramic capacitor and a TVS to
bypass the VCC to GND.
VOUT
VIN
M1
RGATE
10Ω
GATE
CSS
SGM25711B
GND
Figure 15. Simplified Schematic for Using Soft-Start
REVISION HISTORY
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
OCTOBER 2022 ‒ REV.A to REV.A.1
Page
Update Detailed Description........................................................................................................................................................................................ All
Update Application Information section ................................................................................................................................................................12, 18
Changes from Original (OCTOBER 2021) to REV.A
Page
Changed from product preview to production data..................................................................................................................................................... All
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20
PACKAGE INFORMATION
PACKAGE OUTLINE DIMENSIONS
MSOP-10
b
E1
E
4.8
1.02
0.3
e
0.5
RECOMMENDED LAND PATTERN (Unit: mm)
D
L
A
A1
c
θ
A2
Dimensions
In Millimeters
Dimensions
In Inches
Symbol
MIN
MAX
1.100
0.150
0.950
0.280
0.230
3.100
3.100
5.050
MIN
MAX
0.043
0.006
0.037
0.011
0.009
0.122
0.122
0.199
A
A1
A2
b
0.820
0.020
0.750
0.180
0.090
2.900
2.900
4.750
0.032
0.001
0.030
0.007
0.004
0.114
0.114
0.187
c
D
E
E1
e
0.500 BSC
0.020 BSC
L
0.400
0°
0.800
6°
0.016
0°
0.031
6°
θ
NOTES:
1. Body dimensions do not include mode flash or protrusion.
2. This drawing is subject to change without notice.
SG Micro Corp
TX00015.000
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PACKAGE INFORMATION
TAPE AND REEL INFORMATION
REEL DIMENSIONS
TAPE DIMENSIONS
P2
P0
W
Q2
Q4
Q2
Q4
Q2
Q4
Q1
Q3
Q1
Q3
Q1
Q3
B0
Reel Diameter
P1
A0
K0
Reel Width (W1)
DIRECTION OF FEED
NOTE: The picture is only for reference. Please make the object as the standard.
KEY PARAMETER LIST OF TAPE AND REEL
Reel Width
Reel
Diameter
A0
B0
K0
P0
P1
P2
W
Pin1
Package Type
W1
(mm)
(mm) (mm) (mm) (mm) (mm) (mm) (mm) Quadrant
MSOP-10
13″
12.4
5.20
3.30
1.50
4.0
8.0
2.0
12.0
Q1
SG Micro Corp
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TX10000.000
PACKAGE INFORMATION
CARTON BOX DIMENSIONS
NOTE: The picture is only for reference. Please make the object as the standard.
KEY PARAMETER LIST OF CARTON BOX
Length
(mm)
Width
(mm)
Height
(mm)
Reel Type
Pizza/Carton
13″
386
280
370
5
SG Micro Corp
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TX20000.000
相关型号：
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