MAX15091AETI+G3U [MAXIM]
Analog Circuit, 1 Func, BICMOS, TQFN-28;
| 型号： | MAX15091AETI+G3U |
| 厂家： | 
MAXIM INTEGRATED PRODUCTS |
| 描述： | Analog Circuit, 1 Func, BICMOS, TQFN-28 信息通信管理 |
| 文件： | 总17页 (文件大小：902K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
EVALUATION KIT AVAILABLE
MAX15091/MAX15091A
2.7V to 18V, 9A, Integrated Hot-Swap
Solution with Current Report Output
General Description
Benefits and Features
The MAX15091/MAX15091A ICs are integrated solutions
for hot-swap applications requiring the safe insertion and
removal of circuit line cards from a live backplane. The
devices integrate a hot-swap controller, 18mΩ (typ) power
MOSFET, and an electronic circuit-breaker protection in a
single package.
● Integration Reduces Solution Size for Blade Servers
and Other Space-Constrained Designs
• Integrated 18mΩ (typ) Internal Power MOSFET
• Overvoltage Protection
• Power-Good and Fault Outputs
• Analog Current Report Output without Need for
External R
• Thermal Protection
SENSE
The devices integrate an accurate current-sense circuitry
and provide 170µA/A of proportional output current. The
devices are designed for protection of 2.7V to 18V supply
voltages.
● Flexibility Enables Use in Many Unique Designs
• 2.7V to 18V Operating Voltage Range
• Programmable Inrush Current Control Under SOA
Operation
These devices implement a foldback current limit during
startup to control inrush current lowering di/dt and keep the
MOSFET operating under safe operating area (SOA) con-
ditions.After the startup cycle is complete, on-chip compar-
ators provide VariableSpeed/BiLevel™ protection against
short-circuit and overcurrent faults, and immunity against
system noise and load transients. The load is disconnect-
ed in the event of a fault condition. The devices are factory
calibrated to deliver accurate overcurrent protection with
±10% accuracy. During a fault condition, the MAX15091
latches off, while the MAX15091A enters autoretry mode.
• Adjustable Circuit-Breaker Current/Current-Limit
Threshold
• Programmable Slew-Rate Control
• Programmable Undervoltage Lockout
• Variable-Speed Circuit-Breaker Response
• Latchoff or Automatic Retry Options
● Safety Features Ensure Accurate, Robust Protection
• 9A (max) Load Current Capability
• ±10% Circuit-Breaker Threshold Accuracy
• Inrush Current Regulated at Startup with Foldback
• Implementation for di/dt Control
The devices feature an IN to OUT short-circuit detection
before startup. The devices provide a power-MOSFET
GATE pin to program the slew rate during startup by add-
ing an external capacitor. The devices have overvoltage/
undervoltage input pins that can detect an overvoltage/
undervoltage fault and disconnect the IN from the OUT.
Additional features include internal overtemperature pro-
tection, power-good output, and fault-indicator output.
• IN-to-OUT Short-Circuit Detection
Applications
● Blade Servers
● Server I/O Cards
● RAID Systems
● Disk Drive Power
● Storage Applications
● Industrial Applications
The MAX15091/MAX15091A are available in a 28-pin,
5mm x 5mm TQFN power package and are rated over the
-40°C to +85°C extended temperature range.
For related parts and recommended products to use with this
part, refer to www.maximintegrated.com/MAX15091.related.
Ordering Information appears at end of data sheet.
Typical Application Circuit appears at end of data sheet.
VariableSpeed/BiLevel is a trademark of Maxim Integrated
Products, Inc.
19-6625; Rev 2; 1/15
MAX15091/MAX15091A
2.7V to 18V, 9A, Integrated Hot-Swap
Solution with Current Report Output
Absolute Maximum Ratings
CC
V
to GND ..........................................................-0.3V to +20V
Continuous Power Dissipation (T = +70NC)
A
IN to GND..............................................................-0.3V to +20V
TQFN (derate 34.5mW/NC above +70NC)...............2758.6mW
Operating Temperature Range........................... -40NC to +85NC
Junction Temperature......................................................+150NC
Storage Temperature Range............................ -60NC to +150NC
Lead Temperature (soldering, 10s) .................................+300NC
Soldering Temperature (reflow).......................................+260NC
OUT to GND...............................................-0.3V to (V + 0.3V)
IN
GATE to OUT ..........................................................-0.3V to +6V
CDLY, ISENSE to GND ..........................-0.3V to (V
+ 0.3V)
REG
EN, CB, UV, OV to GND .........................................-0.3V to +6V
REG to GND............................-0.3V to min (+6V, (V + 0.3V))
CC
PG, FAULT to GND...............................................-0.3V to +20V
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.
Package Thermal Characteristics (Note 1)
Junction-to-Ambient Thermal Resistance (q ) ..............29°C/W
JA
Junction-to-Case Thermal Resistance (q ).....................2°C/W
JC
Note 1: 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.maximintegrated.com/thermal-tutorial.
Thermal resistance can be lowered with improved board design.
Electrical Characteristics
(V = V
= 2.7V to 18V, T = T = -40°C to +85°C, unless otherwise noted. Typical values are at V = 12V, R
= 25kΩ, and T
CB A
IN
CC
A
J
IN
= +25°C.) (Note 2)
PARAMETER
POWER SUPPLIES
Operating Range
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
V
V
2.7
2.7
18
18
V
V
CC
CC
IN Operating Range
Supply Current
V
IN
V
I
V = 3V
IN
0.4
3.3
0.65
3.6
2
mA
CC
CC
R
= 25kΩ, no load
= 10kΩ, no load
CB
CB
IN Supply Current
I
mA
V
IN
R
1.75
V
Default Undervoltage
CC
V
V
rising
2.35
2.5
0.1
2.65
UVLO
CC
Lockout
V
Default Undervoltage-
CC
V
V
UVLO_HYS
Lockout Hysteresis
REG Regulator Voltage
UV Turn-On Threshold
V
No load, V
> 4V
CC
3
3.3
1.2
3.5
V
V
REG
V
V
V
V
V
rising
1.18
1.22
UV_TH
UV
UV
OV
OV
UV Turn-On Threshold
Hysteresis
V
falling
rising
falling
0.1
1.2
0.1
V
V
V
UV_HYS
OV Turn-On Threshold
V
1.18
0.95
1.22
1.05
OV_TH
OV Turn-On Threshold
Hysteresis
V
OV_HYS
1
V
V
V
V
V
rising
falling
EN Threshold
EN_TH
EN
0.1
V
EN Threshold Hysteresis
EN_HYS
EN
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MAX15091/MAX15091A
2.7V to 18V, 9A, Integrated Hot-Swap
Solution with Current Report Output
Electrical Characteristics (continued)
(V = V
= 2.7V to 18V, T = T = -40°C to +85°C, unless otherwise noted. Typical values are at V = 12V, R
= 25kΩ, and T
CB A
IN
CC
A
J
IN
= +25°C.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
µA
OV, UV, EN Input Leakage
I
-1
+1
V
= V
= V = 0 to 5V
EN
LEAK
OV
UV
Current
CB Source Current
I
Power-on mode
12
µA
THCB_NORM
CURRENT LIMIT
R
= 25kΩ
8
9
3
10
Circuit-Breaker Accuracy
(Note 3)
CB
I
V
= 12V
A
CB,TH
IN
R
= 8.33kΩ
2.7
3.3
CB
Circuit-Breaker Accuracy
Deviation
R
= 8.33kΩ to 25kΩ, compared to
CB
-10
+10
%
nominal current-limit value
0.6% overcurrent
2.7
ms
µs
Slow-Comparator Response
Time (Note 4)
t
SCD
30% overcurrent
200
Maximum Current Limit
During Startup
I
(see Figure 2)
I
I
A
A
LIM
CB,TH
1.5 x
Fast-Comparator Threshold
I
FC_TH
CB,TH
Fast-Comparator Response
Time
t
200
35
ns
FCD
Minimum CB Voltage
Reference During Foldback
(Note 5)
V
V
V
- V
- V
> 10V, R = 25kΩ
CB
mV
mV
THCB_MIN
IN
OUT
Maximum CB Voltage
Reference During Foldback
(Note 5)
V
< 2V, R
= 25kΩ
150
THCB_MAX
IN
OUT
CB
TIMING
Startup Maximum Time
Duration
t
43
48
3.2
2
53
ms
s
SU
t
RESTART
Autorestart Delay Time
Time Delay Comparator
High Threshold
V
1.85
1.6
2.15
2.2
V
DLY_TH
Time Delay Pullup Current
I
1.9
12
µA
ms
DLY
Output Short Detection at
Startup
t
10.8
13.2
SHORT
MOSFET
T
T
= +25°C
18
23
27
A
Total On-Resistance
GATE Charge Current
R
mΩ
ON
= -40°C to +85°C
A
I
4.56
5.7
6.84
µA
GATE
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MAX15091/MAX15091A
2.7V to 18V, 9A, Integrated Hot-Swap
Solution with Current Report Output
Electrical Characteristics (continued)
(V = V
= 2.7V to 18V, T = T = -40°C to +85°C, unless otherwise noted. Typical values are at V = 12V, R
= 25kΩ, and T
CB A
IN
CC
A
J
IN
= +25°C.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
OUTPUTS
Low-impedance state,
= +5mA, I = +5mA
FAULT, PG Output Low
Voltage
V
0.4
1
V
OL
I
FAULT
PG
High-impedance state,
= 16V, V = 16V
FAULT, PG Output High
Leakage Current
I
µA
OH
V
FAULT
PG
CURRENT REPORT
ISENSE Full-Scale Current
ISENSE Gain Ratio
I
1.53
170
mA
µA/A
V
ISENSE
ISENSE/I
OUT
ISENSE Voltage Range
V
V
= 12V
0
2.5
ISENSE
IN
T
T
T
T
= +25°C
-32
-45
-3
+32
+45
+3
A
A
A
A
ISENSE Offset Error
I
µA
%
ISENSE_OFF
= -40°C to +85°C
= +25°C
ISENSE Gain Error
PG THRESHOLD
PG Threshold
I
ISENSE_ERROR
= -40°C to +85°C
-5.5
+5.5
0.9 x
V
Measured at V
, V = 12V
OUT IN
V
ms
V
PG
V
IN
From V
(V
> V
and
OUT
PG
PG Assertion Delay
t
12
16
20
PG
- V ) > 3V
IN
GATE
OUT to IN Short-Circuit
Detection Threshold
0.9 x
V
IN
V
Measured at V
Measured at V
, V = 12V
OUT IN
IOSHT
0.5 x
OUT Precharge Threshold
V
, V = 12V
OUT IN
V
PC
SD
V
IN
THERMAL SHUTDOWN
Thermal Shutdown
T
T rising
+150
20
°C
°C
J
Thermal-Shutdown Hysteresis
T falling
J
Note 2: All devices are 100% production tested at T = +25°C. Limits over temperature are guaranteed by design.
A
Note 3: 25kΩ is the maximum allowed external resistance value to be connected at CB pin to GND for safe operation. All devices
are tested with 8.33kΩ, the parameter specified at R = 25kΩ is guaranteed by bench characterization and correlation,
CB
with respect to the tested parameter at R
= 8.33kΩ. The formula that describes the relationship between R
and the
CB
CB
circuit-breaker current threshold is: I
= R /2777.8.
CB
CB
Note 4: The current-limit slow-comparator response time is weighed against the amount of overcurrent so the higher the
overcurrent condition, the faster the response time.
Note 5: Foldback is active during the startup phase so the internal power MOSFET operates within SOA.
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MAX15091/MAX15091A
2.7V to 18V, 9A, Integrated Hot-Swap
Solution with Current Report Output
Typical Operating Characteristics
(V = V
= 2.7V to 18V, T = -40°C to +85°C, unless otherwise noted. Typical values are at V = 12V, R
= 25kΩ, and
IN
CC
J
IN
CB
T = +25°C.) (Note 3)
J
IN SUPPLY CURRENT
vs. TEMPERATURE
CIRCUIT-BREAKER THRESHOLD
vs. CIRCUIT-BREAKER RESISTANCE
3.30
3.25
3.20
3.15
12
10
8
V
IN
= 12V
V = 12V
IN
6
4
2
3.10
-40
0
-15
10
35
60
85
5
10
15
(Ω)
20
25
TEMPERATURE (°C)
R
CB
CIRCUIT-BREAKER THRESHOLD
vs. TEMPERATURE
ON-RESISTANCE vs. TEMPERATURE
25
20
15
10
14
12
10
8
V
= 12V
= 1A
V
IN
= 12V
IN
I
LOAD
R
R
= 25kΩ
= 20kΩ
= 15kΩ
CB
CB
CB
R
6
4
R
= 8.2kΩ
CB
2
0
-40
-15
10
35
60
85
-40
-15
10
35
60
85
TEMPERATURE (°C)
TEMPERATURE (°C)
TURN-ON WAVEFORM
NORMAL TURN-OFF WAVEFORM
MAX15091 toc06
MAX15091 toc05
I
= 3.5A
LOAD
V
V
UV
UV
I
= 3.5A
LOAD
2V/div
2V/div
0V
0V
0V
0V
V
V
OUT
10V/div
OUT
10V/div
V
PG
V
PG
10V/div
10V/div
0V
0A
0V
0A
I
I
LOAD
5A/div
LOAD
5A/div
10ms/div
10ms/div
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MAX15091/MAX15091A
2.7V to 18V, 9A, Integrated Hot-Swap
Solution with Current Report Output
Typical Operating Characteristics (continued)
(V = V
= 2.7V to 18V, T = -40°C to +85°C, unless otherwise noted. Typical values are at V = 12V, R
= 25kΩ, and
IN
CC
J
IN
CB
T = +25°C.) (Note 3)
J
FAULT-SHUTDOWN WAVEFORM
OVERLOAD (SLOW TRIP)
FAULT-SHUTDOWN WAVEFORM
OVERLOAD (SHORT CIRCUIT)
MAX15091 toc07
MAX15091 toc08
V
V
OUT
OUT
10V/div
10V/div
0V
0A
0V
I
LOAD
I
LOAD
10A/div
5A/div
0A
0V
V
V
PG
10V/div
PG
10V/div
0V
0V
V
V
FAULT
10V/div
FAULT
10V/div
0V
1ms/div
1ms/div
CIRCUIT-BREAKER THRESHOLD
vs. TEMPERATURE
PG ASSERTION DELAY
MAX15091 toc10
1.4
1.3
1.2
1.1
1.0
V
IN
= 12V
V
UV
1V/div
V
RISING
UV
0V
V
OUT
5V/div
V
PG
0V
0V
5V/div
V
FALLING
35
UV
-40
-15
10
60
85
10ms/div
TEMPERATURE (°C)
CIRCUIT-BREAKER THRESHOLD TIME
vs. OVERCURRENT
AUTORETRY FUNCTIONALITY
MAX15091 toc11
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
V
IN
= 12V
V
OUT
10V/div
0V
0A
I
LOAD
10A/div
V
PG
10V/div
0V
0V
V
FAULT
10V/div
1s/div
0
5
10
15
20
25
30
OVERCURRENT (%)
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MAX15091/MAX15091A
2.7V to 18V, 9A, Integrated Hot-Swap
Solution with Current Report Output
Pin Configuration
TOP VIEW
21 20 19 18 17 16 15
14
13
OV 22
UV 23
GND
PG
12 FAULT
24
25
26
27
28
REG
MAX15091
MAX15091A
EN
11
10
9
GND
GND
CDLY
GATE
CB
*EP
6
+
8
V
ISENSE
CC
1
2
3
4
5
7
TQFN
*CONNECT EXPOSED PAD TO GND.
Pin Description
PIN
NAME
FUNCTION
Supply Voltage Input. IN is connected to the drain of the internal 18mΩ MOSFET. Bypass IN with a
transient voltage-suppressor diode to GND for clamping inductive kick transients in the case of fast
output short-circuit to GND.
1–7
IN
Power-Supply Input. Connect V
to a voltage between 2.7V and 18V. Connect a Schottky diode (or
CC
8
9
V
10Ω resistor) from IN to V
and a 1µF bypass capacitor to GND to guarantee full operation in the event
CC
CC
V
collapses during a strong short from OUT to GND.
IN
GATE of Internal MOSFET. During startup, a 5.7µA current is sourced to enhance the internal MOSFET
with a 10V/ms slew rate. Connect an external capacitance from GATE to GND to reduce the output slew
rate during startup.
GATE
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MAX15091/MAX15091A
2.7V to 18V, 9A, Integrated Hot-Swap
Solution with Current Report Output
Pin Description (continued)
PIN
NAME
FUNCTION
Enable Timer Input. Connect a capacitor between CDLY and GND to set a 1s/µF duration timeout
delay. The EN input has to be pulled low before the timeout delay elapses, to prevent internal
MOSFET shutdown after power-up.
10
CDLY
Enable Input. Externally pulled up to logic-high state through a resistor normally connected to REG. The
EN input must be pulled down (for at least 1ms) by the external circuit before a programmable timeout
delay has elapsed, otherwise a shutdown occurs. The timeout timer starts counting when the internal
MOSFET is turned on. Connect a capacitor between CDLY and GND to program the duration of the
timeout delay. Connect EN to GND to disable this feature.
11
EN
Fault Status Output. FAULT is an open-drain, active-low output. FAULT asserts low when an overcurrent
or overtemperature condition triggers a shutdown. FAULT is disabled during startup.
12
13
FAULT
Power-Good Output. PG is an open-drain, active-high output. PG pulls low until the internal power
MOSFET is fully enhanced.
PG
14, 25, 26
15–21
GND
Ground
OUT
Load Output. Source of the internal power MOSFET.
Overvoltage Enable Input. Pull OV high to turn off the internal MOSFET. Connect OV to an external
resistive divider to set the overvoltage-disable threshold. See the Setting the Overvoltage Threshold
section.
22
OV
Active-High Enable Comparator Input. Pulling UV high enables the internal MOSFET to turn on. UV also
sets the undervoltage threshold. See the Setting the Undervoltage Threshold section.
23
24
UV
Internal Regulator Output. Bypass to ground with a 1µF capacitor. Do not power external circuitry using
the REG output (except a resistor > 50kΩ connected from REG to EN).
REG
Current-Limit Threshold Set. Connect a resistor from CB to GND to set the circuit-breaker threshold. Maximum
value of 25kΩ can be accepted for safe operation. Having the CB pin connected to GND sets the circuit-
breaker threshold at 0A.
27
28
CB
Current-Sense Output. The ISENSE output sources a current that is proportional to the output current.
Connect a resistor between ISENSE and GND to produce a scaled voltage.
ISENSE
Exposed Pad. Connect EP to GND externally. Do not use EP as an electrical connection to GND. EP
is internally connected to GND through a resistive path and must be connected to GND externally. To
optimize power dissipation, solder the exposed pad to a large copper power plane. Do not leave EP
unconnected.
—
EP
V
is high (V
> 1.2V) and V
is low (V
< 1.2V).
OV
falls below
UV
UV
OV
Detailed Description
The devices turn off the output when V
(1.2V - V
resistive divider from IN to UV, OV, and ground provide
the flexibility to set the undervoltage/overvoltage-lockout
threshold to any desired level between V
See Figure 1 and the Setting the Undervoltage Threshold
and Setting the Overvoltage Threshold sections.
UV
Enable Logic and Undervoltage/
Overvoltage-Lockout Threshold
The MAX15091/MAX15091A ICs enable the output, as
) or V
rises above 1.2V. An external
UV_HYS
OV
shown in Table 1. The devices are ready to drive the out-
and 18V.
UVLO
put when the V
supply rises above the V
thresh-
CC
UVLO
CC
old. The devices turn on the output when V
> V
,
UVLO
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MAX15091/MAX15091A
2.7V to 18V, 9A, Integrated Hot-Swap
Solution with Current Report Output
Table 1. Output Enable Truth Table
POWER SUPPLY
PRECISION ANALOG INPUTS
UV OV
OUT
V
CC
V
V
> V
< V
X
V
> V
V
< V
X
On
Off
Off
Off
CC
UVLO
UVLO
UV
UV_TH
OV
OV_TH
X
CC
V
< (V
- V )
UV_HYS
X
UV
UV_TH
X
X
V
> V
OV
OV_TH
X = Don’t care.
V
and V
= 1.2V (typ).
UV_TH
OV_TH
An internal 48ms timer starts counting when the devices
enter the startup phase. The devices complete the startup
phase and enter normal operation mode if the voltage
IN
at OUT rises above the precharge threshold (0.9 x V )
IN
MAX15091
MAX15091A
and (V
- V
) > 3V. An open-drain power-good
OUT
GATE
R1
output (PG) goes high-impedance 16ms after the startup
successfully completes.
UV
The thermal-protection circuit is always active and the
internal MOSFET immediately turned off when the
thermal-shutdown threshold condition is reached.
CONTROL
LOGIC
R2
R3
1.2V
VariableSpeed/BiLevel Fault Protection
OV
VariableSpeed/BiLevel fault protection incorporates com-
parators with different thresholds and response times to
monitor the load current (Figure 3). Protection is provided
in normal operation (after the startup period has expired)
by discharging the MOSFET gate in response to a fault
condition. During a fault condition, the MAX15091A enters
autoretry mode, while the MAX15091 latches off (see the
Autoretry and Latch-Off Fault Management section).
GND
Figure 1. Undervoltage/Overvoltage-Threshold Setting
Enable Input (EN)
Startup
After a startup phase is successfully completed and the
Once the device output is enabled, the device provides
controlled application of power to the load. The voltage at
OUT begins to rise at approximately 10V/ms default until
the programmed circuit-breaker current level is reached,
while the devices actively limit the inrush current at the
circuit-breaker setting. An external capacitor connected to
the GATE pin allows the user to program the slew rate to
a value lower than the default. The inrush current can be
power-good output asserted, the EN input has to be pulled
low (for at least 1ms) before the t
EN input is not pulled low before the t
the devices turn off the internal MOSFET immediately
and a new cycle is required for entering power-up mode.
Connect a capacitor between CDLY and GND to set a 1s/
µF duration timeout delay. If this function in is not imple-
mented, connect EN to GND for proper operation.
delay elapses. If the
DLY
elapses, then
DLY
programmed by selecting the appropriate value of R
.
CB
During startup, a foldback current limit is active to protect
the internal MOSFET to operate within the SOA (Figure 2).
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MAX15091/MAX15091A
2.7V to 18V, 9A, Integrated Hot-Swap
Solution with Current Report Output
I
INRUSH
R
CB
= 25kΩ
4.5A
R
CB
= 8.33kΩ
1.5A
1A
0.25A
V - V
IN OUT
2V
10V
Figure 2. Startup Inrush Current Foldback Characteristics
SLOW COMPARATOR
2.7ms
200µs
FAST COMPARATOR
200ns
0.6%
30%
50%
OVERCURRENT
OVERCURRENT OVERCURRENT
OUT CURRENT
Figure 3. VariableSpeed/BiLevel Response
Maxim Integrated
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MAX15091/MAX15091A
2.7V to 18V, 9A, Integrated Hot-Swap
Solution with Current Report Output
The devices also feature catastrophic short-circuit protec-
tion. During normal operation, if OUT is shorted directly
to GND, a fast protection circuit forces the gate of the
internal MOSFET to discharge quickly and disconnect the
output from the input.
Charge Pump
An integrated charge pump provides the gate-drive volt-
age for the internal power MOSFET. The charge pump
generates the proper gate drive voltage above V to fully
enhance the internal power MOSFET and guarantee low
IN
R
operation during normal state conditions.
ON
Autoretry and Latch-Off Fault Management
During startup, the internal charge pump drives the GATE
of the MOSFET with a fixed 5.7µA current to enhance the
internal MOSFET with 10V/ms slew rate (typ). Connect
During a fault condition, the devices turn off the internal
MOSFET, disconnecting the output from the input. The
MAX15091A enters autoretry mode and restarts after
an external capacitor (C
) from GATE to GND to
GATE
a t
time delay has elapsed. The MAX15091
RESTART
reduce the output slew rate during startup. C
can be
GATE
latches off and remains off until the enable logic is cycled
off and on after a t delay. The delay prevents
calculated according to the following formula:
RESTART
the latch-off device to restart and operate with an unsafe
power-dissipation duty cycle.
C
= (I x ∆t)/∆V
GATE
GATE
GATE
where I
is 5.7µA (typ), Dt is the desired slew-rate
GATE
time, and ∆V
MOSFET at turn-on.
is the voltage at the gate of the internal
GATE
Fault-Status Output (FAULT)
FAULT is an open-drain output that asserts low when
a current-limit or an overtemperature-fault shutdown
occurs. FAULT remains low until the next startup cycle.
FAULT is capable of sinking up to 5mA current when
asserted.
The slew rate of the OUT pin during startup can be
controlled by I
conditions, or by the limited inrush current and the exter-
nal capacitive load, whichever is less.
/C
under light-load driving
GATE GATE
(∆V
/∆t) = I /C
LIM LOAD
OUT
Power-Good (PG) Delay
The devices feature an open-drain, power-good output
Circuit-Breaker Comparator
and Current Limit
The current that passes through the internal power
MOSFET is compared to a circuit-breaker threshold. An
external resistor between CB and GND sets this threshold
according to the following formula:
that asserts after a t
delay, indicating that the OUT volt-
PG
age has reached (0.9 x V ) voltage and (V
- V
)
IN
GATE
OUT
> 3V.
Internal Regulator Output (REG)
The devices include a linear regulator that outputs 3.3V
at REG. REG provides power to the internal circuit blocks
of the devices and must not be loaded externally (except
for a resistor > 50kΩ connected from REG to EN). REG
requires at least a 1µF capacitor to ground for proper
operation.
I
= R /2777.8
CB
CB
where I
is in amps and R
(the resistor between CB
CB
CB
and GND) is in ohms.
The circuit-breaker comparator is designed so the load
current can exceed the threshold for some amount of
time before tripping. The time delay varies inversely with
the overdrive above the threshold. The greater the over-
current condition, the faster the response time, allowing
the devices to tolerate load transients and noise near the
circuit-breaker threshold. The maximum allowed external
resistor value is 25kΩ, which corresponds to a 9A CB
threshold setting. Programming the CB threshold to a
value higher than 9A could cause unsafe operating condi-
tions, resulting in damage to the devices.
Current Report Output (ISENSE)
The ISENSE pin is the output of an accurate current-
sense amplifier and provides a source current that is pro-
portional to the load current flowing into the main switch.
The factory-trimmed current ratio is set to 170µA/A.
This produces a scaled voltage by connecting a resistor
between ISENSE
ground. This voltage signal then
and
goes to an ADC and provides digitized information of the
current supplied to the powered system.
Maxim Integrated
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MAX15091/MAX15091A
2.7V to 18V, 9A, Integrated Hot-Swap
Solution with Current Report Output
the following equation to calculate the resistor values for
the desired undervoltage threshold:
Thermal Protection
The devices enter a thermal-shutdown mode in the event
of overheating caused by excessive power dissipation or
high ambient temperature. When the junction temperature
V
IN
UV_TH
R1 =
- 1 × R2 + R3
(
)
V
exceeds T = +150°C (typ), the internal thermal-protec-
J
tion circuitry turns off the internal power MOSFET. The
devices recover from thermal-shutdown mode once the
junction temperature drops by 20°C (typ).
where V is the desired turn-on voltage for the output
IN
UV_TH
and V
divider from IN to UV. During normal operating conditions,
must remain above its 1.2V (typ) threshold. If V
is 1.2V. R1 and (R2 + R3) create a resistive
IN to OUT Short-Circuit Protection
At startup, after all the input conditions are satisfied (UV,
V
UV
UV
falls 100mV (V
) below the threshold, the internal
UV_HYS
OV, V
), the devices immediately check for an IN to
UVLO
MOSFET turns off, disconnecting the load from the input.
OUT short-circuit fault. If V
is greater than 90% of
OUT
Setting the Overvoltage Threshold
The devices also feature an independent overvoltage-
V , the internal MOSFET cannot be turned on so FAULT
IN
is asserted and the MAX15091A enters autoretry mode in
enable control (OV) for the internal MOSFET.
3.2s, while the MAX15091 latches off.
When V
exceeds the 1.2V (typ) threshold, the internal
If V
is lower than 90% of V but greater than 50%
IN
OV
OUT
MOSFET turns off.
of V , the internal MOSFET still cannot be turned on. No
IN
fault is asserted and the MOSFET can turn on as soon as
The overvoltage-lockout threshold is programmable using
a resistive divider from IN to UV, OV, and GND (Figure 1).
Use the following equation to calculate the resistor values
for the desired overvoltage threshold:
V
OUT
is lower than 50% of V .
IN
Applications Information
Setting the Undervoltage Threshold
V
IN
OV_TH
The devices feature an independent on/off control (UV)
for the internal MOSFET. The devices operate with a 2.7V
to 18V input voltage range and have a default 2.5V (typ)
undervoltage-lockout threshold.
R1 + R2 =
- 1 × R3
(
)
V
where V is the desired turn-off voltage for the output
IN
OV_TH
and V
divider from IN to OV. During normal operating conditions,
must remain below its 1.2V (typ) threshold. If V
is 1.2V. R1 and (R2 + R3) create a resistive
The internal MOSFET remains off as long as V
< 2.5V
CC
or V
< V
. The undervoltage-lockout threshold
UV
UV_TH
V
OV
OV
is programmable using a resistive divider from IN to UV,
OV, and GND (Figure 1). When V is greater than 2.7V
rises above the V
threshold, the internal MOSFET
OV_TH
CC
turns off and disconnects the load from the input.
and V
exceeds the 1.2V (typ) threshold, the internal
UV
MOSFET turns on and goes into normal operation. Use
Maxim Integrated
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MAX15091/MAX15091A
2.7V to 18V, 9A, Integrated Hot-Swap
Solution with Current Report Output
Functional Diagram
I
LOAD
M
POW
IN
OUT
I
/5882
LOAD
I
REF
M
S1
V
CC
ISENSE
FAULT
CHARGE
PUMP
MAX15091
MAX15091A
I
GATE
GATE
CB_SLOW_COMP
I
PD
UV
OV
CONTROL
LOGIC
2 x I
SLEW
1.2V
FAST_COMP
GATE
STARTUP
CONTROL AND
FOLDBACK
TEMP
SENSE
V
CC
GATE_OK
PG
1.2V
LDO
REGULATOR
REFERENCE
GENERATOR
0.9 x V
IN
12µA
1.9µA
CB
CDLY
2V
DLY
CTRL
EN
REG
GND
Maxim Integrated
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MAX15091/MAX15091A
2.7V to 18V, 9A, Integrated Hot-Swap
Solution with Current Report Output
Typical Application Circuit
12V
IN
OUT
TVS
GATE
R
IN
V
C
GATE
CC
R1
DC-DC
REGULATOR
3.3V OUTPUT
C
IN
UV
R
PG
R
FAULT
MAX15091
MAX15091A
CB
PG
REG
FAULT
ISENSE
R2
R3
R
CB
C
REG
A/D
CONVERTER
R
ISENSE
OV
EN
CDLY
C
CDLY
GND
Ordering Information
Package Information
For the latest package outline information and land patterns
(footprints), go to www.maximintegrated.com/packages. Note
that a “+”, “#”, or “-” in the package code indicates RoHS status
only. Package drawings may show a different suffix character, but
the drawing pertains to the package regardless of RoHS status.
TEMP
PART
PIN-
FAULT
RANGE PACKAGE MANAGEMENT
-40NC to
+85NC
28 TQFN-
MAX15091ETI+
Latched Off
EP*
PACKAGE
TYPE
PACKAGE
CODE
OUTLINE
NO.
LAND PATTERN
NO.
-40NC to
+85NC
28 TQFN-
MAX15091AETI+
Autoretry
EP*
28 TQFN
T2855+8
21-0140
90-0028
+Denotes a lead(Pb)-free/RoHS-compliant package.
*EP = Exposed pad.
Chip Information
PROCESS: BiCMOS
Maxim Integrated
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MAX15091/MAX15091A
2.7V to 18V, 9A, Integrated Hot-Swap
Solution with Current Report Output
Revision History
REVISION
NUMBER
REVISION
DATE
PAGES
CHANGED
DESCRIPTION
0
1
2
3/13
9/13
1/15
Initial release
—
14
1
Removed future product marking from MAX15091A
Updated Benefits and Features section
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim Integrated’s website at www.maximintegrated.com.
Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses
are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits)
shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance.
©
Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc.
2015 Maxim Integrated Products, Inc.
│ 15
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