MAXIM MAX15090A

EVALUATION KIT AVAILABLE
MAX15090/MAX15090A
2.7V to 18V, 12A, Hot-Swap Solution
with Current Report Output
General Description
The MAX15090/MAX15090A 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, 6mω power
MOSFET, and an electronic circuit-breaker protection in
a single package.
The devices integrate an accurate current-sense circuitry
and provide 220FA/A of proportional output current.
The devices are designed for protection of 2.7V to 18V
supply voltages.
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) conditions. After the startup cycle is complete, on-chip comparators provide VariableSpeed/BiLevelK protection against
short-circuit and overcurrent faults, and immunity against
system noise and load transients. The load is disconnected
in the event of a fault condition. The devices are factory
calibrated to deliver accurate overcurrent protection with
Q10% accuracy. During a fault condition, the MAX15090
latches off, while the MAX15090A enters autoretry mode.
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 adding 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 protection, power-good output, and fault-indicator output.
The MAX15090/MAX15090A are available in a 28-bump,
2.07mm x 3.53mm, power wafer-level package (WLP)
and are rated over the -40°C to +85°C extended
temperature range.
Features
S 2.7V to 18V Operating Voltage Range
S 6mω (typ) Internal Power MOSFET
S 12A (max) Load Current Capability
S Current Reporting without Need for External
RSENSE
S Q10% Circuit-Breaker Threshold Accuracy
S Adjustable Circuit-Breaker Current/Current-Limit
Threshold
S Programmable Slew-Rate Control
S Variable-Speed Circuit-Breaker Response
S Inrush Current Regulated at Startup with Foldback
Implementation for di/dt Control
S Thermal Protection
S Overvoltage Protection
S Power-Good and Fault Outputs
S Latch-Off or Automatic Retry Options
S Programmable Undervoltage Lockout
S IN to OUT Short-Circuit Detection
Applications
RAID Systems
Storage Bridge Bay
Disk Drive Power
Server I/O Cards
Industrial
Ordering Information appears at end of data sheet.
For related parts and recommended products to use with this part,
refer to www.maximintegrated.com/MAX15090.related.
Typical Application Circuit appears at end of data sheet.
VariableSpeed/BiLevel is a trademark of Maxim Integrated
Products, Inc.
For pricing, delivery, and ordering information, please contact Maxim Direct
at 1-888-629-4642, or visit Maxim’s website at www.maximintegrated.com.
19-6480; Rev 1; 12/12
MAX15090/MAX15090A
2.7V to 18V, 12A, Hot-Swap Solution
with Current Report Output
Absolute Maximum Ratings
VCC to GND............................................................-0.3V to +20V
IN to GND...............................................................-0.3V to +20V
OUT to GND................................................-0.3V to (VIN + 0.3V)
GATE to OUT............................................................-0.3V to +6V
CDLY, ISENSE to GND............................-0.3V to (VREG + 0.3V)
EN, CB, UV, OV to GND..........................................-0.3V to +6V
REG to GND.............................-0.3V to min (+6V, (VCC + 0.3V))
PG, FAULT to GND................................................-0.3V to +20V
Continuous Power Dissipation (TA = +70NC)
WLP (derate 23.8mW/NC above +70NC).....................1500mW
Operating Temperature Range........................... -40NC to +85NC
Junction Temperature......................................................+150NC
Storage Temperature Range............................. -60NC to +150NC
Lead Temperature (soldering, 10s).................................+300NC
Soldering Temperature (reflow).......................................+260NC
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 (qJA)...............42°C/W
Junction-to-Case Thermal Resistance (qJC)......................7°C/W
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
(VIN = VCC = 2.7V to 18V, TA = TJ = -40°C to +85°C, unless otherwise noted. Typical values are at VIN = 12V, RCB = 33.2kω, and
TA = +25°C.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
POWER SUPPLIES
VCC Operating Range
VCC
2.7
18
V
IN Operating Range
VIN
2.7
18
V
VCC Supply Current
ICC
mA
IN Supply Current
IIN
VCC Default Undervoltage
Lockout
VUVLO
VCC Default UndervoltageLockout Hysteresis
VUVLO_HYS
VIN = 3V
0.5
0.75
RCB = 40.2kω, no load
5.1
6.2
RCB = 10kω, no load
1.4
1.8
2.5
2.65
VCC rising
2.35
0.1
mA
V
V
No load, VCC > 4V
3.15
3.35
3.55
V
VUV_TH
VUV rising
1.21
1.23
1.25
V
UV Turn-On Threshold
Hysteresis
VUV_HYS
VUV falling
OV Turn-On Threshold
VOV_TH
VOV rising
OV Turn-On Threshold
Hysteresis
VOV_HYS
VOV falling
VEN_TH
VEN rising
REG Regulator Voltage
VREG
UV Turn-On Threshold
EN Threshold
EN Threshold Hysteresis
Maxim Integrated
VEN_HYS
VEN falling
0.1
1.21
1.23
V
1.25
0.1
0.95
1
0.1
V
V
1.05
V
V
2
MAX15090/MAX15090A
2.7V to 18V, 12A, Hot-Swap Solution
with Current Report Output
ELECTRICAL CHARACTERISTICS (continued)
(VIN = VCC = 2.7V to 18V, TA = TJ = -40°C to +85°C, unless otherwise noted. Typical values are at VIN = 12V, RCB = 33.2kω, and
TA = +25°C.) (Note 2)
PARAMETER
OV, UV, EN Input Leakage
Current
CB Source Current
SYMBOL
ILEAK
ITHCB_NORM
CONDITIONS
VOV = VUV = VEN = 0 to 5V
MIN
TYP
-1
Power-on mode
MAX
UNITS
+1
FA
12
FA
CURRENT LIMIT
Circuit-Breaker Accuracy
(Note 3)
ICB,TH
Circuit-Breaker Accuracy
Deviation
Slow-Comparator Response
Time (Note 4)
tSCD
Maximum Current Limit During
Startup
ILIM
10.85
12.06
13.27
RCB = 10kω
2.7
3
3.3
RCB = 10kω to 40.2kω, compared to
nominal current-limit value
-10
VIN = 12V
RCB = 40.2kω
+10
A
%
0.6% overcurrent
2.7
ms
30% overcurrent
200
Fs
ICB,TH
A
(see Figure 2)
Fast-Comparator Threshold
IFC_TH
1.5 x
ICB,TH
A
Fast-Comparator Response
Time
tFCD
200
ns
Minimum CB Voltage Reference
During Foldback (Note 5)
VTHCB_MIN
VIN - VOUT > 10V, RCB = 40.2kω
60
mV
Maximum CB Voltage
Reference During Foldback
(Note 5)
VTHCB_MAX
VIN - VOUT < 2V, RCB = 40.2kω
240
mV
TIMING
Startup Maximum Time Duration
tSU
43
48
53
ms
Autorestart Delay Time
tRESTART
Time Delay Comparator High
Threshold
VDLY_TH
1.85
2
2.15
V
Time Delay Pullup Current
IDLY
1.6
1.9
2.2
FA
Output Short Detection at
Startup
tSHORT
10.8
12
13.2
ms
5.5
7.5
3.2
s
MOSFET
Total On-Resistance
RON
GATE Charge Current
IGATE
Maxim Integrated
TA = +25°C
TA = -40°C to +85°C
9
4.5
5.7
7
mω
FA
3
MAX15090/MAX15090A
2.7V to 18V, 12A, Hot-Swap Solution
with Current Report Output
ELECTRICAL CHARACTERISTICS (continued)
(VIN = VCC = 2.7V to 18V, TA = TJ = -40°C to +85°C, unless otherwise noted. Typical values are at VIN = 12V, RCB = 33.3kω, and
TA = +25°C.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
0.4
V
1
FA
OUTPUTS
FAULT, PG Output Low Voltage
VOL
Low-impedance state,
IFAULT = +5mA, IPG = +5mA
FAULT, PG Output High
Leakage Current
IOH
High-impedance state,
VFAULT = 16V, VPG = 16V
CURRENT REPORT
ISENSE Full-Scale Current
ISENSE Gain Ratio
ISENSE Voltage Range
2.64
IISENSE
ISENSE/IOUT
VISENSE
ISENSE Offset Error
IISENSE_OFF
ISENSE Gain Error
IISENSE_ERROR
VIN = 12V
mA
220
FA/A
0
2.5
TA = +25°C
-30
+30
TA = -40°C to +85°C
-50
+50
TA = +25°C
-2.5
-2.5
-4
+4
TA = -40°C to +85°C
V
FA
%
PG THRESHOLD
PG Threshold
VPG
Measured at VOUT
PG Assertion Delay
tPG
From VOUT > VPG and
(VGATE - VIN) > 3V
OUT to IN Short-Circuit
Detection Threshold
OUT Precharge Threshold
0.9 x
VIN
12
16
V
20
ms
VIOSHT
Measured at VOUT
0.9 x
VIN
VPC
Measured at VOUT
0.5 x
VIN
V
TSD
TJ rising
+150
°C
TJ falling
20
°C
THERMAL SHUTDOWN
Thermal Shutdown
Thermal-Shutdown Hysteresis
Note 2: All devices are 100% production tested at TA = +25°C. Limits over temperature are guaranteed by design.
Note 3: 40.2kω is the maximum allowed external resistance value to be connected at CB pin to GND for safe operation. All devices are tested with10kω, the parameter specified at RCB = 40.2kω is guaranteed by bench characterization and correlation, with respect to the tested parameter at RCB = 10kω. The formula that describes the relationship between RCB and
the circuit-breaker current threshold is: ICB = RCB/3333.3.
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.
Maxim Integrated
4
MAX15090/MAX15090A
2.7V to 18V, 12A, Hot-Swap Solution
with Current Report Output
Typical Operating Characteristics
(VIN = VCC = 2.7V to 18V, TJ = -40°C to +85°C, unless otherwise noted. Typical values are at VIN = 12V, RCB = 33.2kω, and
TJ = +25°C.) (Note 3)
5.10
5.05
5.00
-15
-40
ON-RESISTANCE (mI)
35
60
85
8
6
4
2
14
RCB = 40kI
VIN = 12V
12
RCB = 30kI
10
8
RCB = 20kI
6
RCB = 10kI
4
2
0
0
10
15
20
25
30
35
-40
40
-15
10
35
60
85
TEMPERATURE (°C)
RCB (I)
ON-RESISTANCE vs. TEMPERATURE
TURN-ON WAVEFORM
NORMAL TURN-OFF WAVEFORM
MAX15090 toc05
VIN = 12V
ILOAD = 1A
MAX15090 toc03
10
TEMPERATURE (°C)
MAX15090 toc04
7
10
VIN = 12V
CIRCUIT-BREAKER THRESHOLD (A)
5.15
12
MAX15090 toc02
IN SUPPLY CURRENT (mA)
VIN = 12V
CIRCUIT-BREAKER THRESHOLD (A)
MAX15090 toc01
5.20
CIRCUIT-BREAKER THRESHOLD
vs. TEMPERATURE
CIRCUIT-BREAKER THRESHOLD
vs. CIRCUIT-BREAKER RESISTANCE
IN SUPPLY CURRENT vs. TEMPERATURE
MAX15090 toc06
0V
VUV
2V/div
0V
VUV
2V/div
0V
VOUT
10V/div
0V
VOUT
10V/div
0V
VPG
10V/div
0V
VPG
10V/div
ILOAD
10A/div
0A
6
5
ILOAD = 6A
0A
4
-40
-15
10
35
60
85
10ms/div
ILOAD = 6A
ILOAD
10A/div
10ms/div
TEMPERATURE (°C)
Maxim Integrated
5
MAX15090/MAX15090A
2.7V to 18V, 12A, Hot-Swap Solution
with Current Report Output
Typical Operating Characteristics (continued)
(VIN = VCC = 2.7V to 18V, TJ = -40°C to +85°C, unless otherwise noted. Typical values are at VIN = 12V, RCB = 33.2kω, and
TJ = +25°C.) (Note 3)
UV RISING /FALLING THRESHOLD
VOLTAGE vs. TEMPERATURE
FAULT-SHUTDOWN
WAVEFORM OVERLOAD (SHORT CIRCUIT)
MAX15090 toc07
MAX15090 toc08
1.3
MAX15090 toc09
FAULT-SHUTDOWN
WAVEFORM OVERLOAD (SLOW TRIP)
0V
VOUT
10V/div
0V
ILOAD
10A/div
0A
VPG
10V/div
0V
VFAULT
10V/div
0V
ILOAD
10A/div
0A
VPG
10V/div
0V
VFAULT
10V/div
0V
1ms /div
UV RISING/FALLING THRESHOLD (A)
VIN = 12V
VOUT
10V/div
VUV RISING
1.3
1.2
VUV FALLING
1.2
1.1
-40
1ms/div
-15
10
35
60
85
TEMPERATURE (°C)
CIRCUIT-BREAKER THRESHOLD TIME
vs. OVERCURRENT
AUTORETRY FUNCTIONALITY
MAX15090 toc10
VUV
1V/div
0V
VOUT
5V/div
0A
VOUT
10V/div
0V
VPG
5V/div
0V
ILOAD
10A/div
VPG
10V/div
0V
0V
VFAULT
10V/div
0V
10ms/div
1s/div
CIRCUIT-BREAKER THRESHOD TIME (ms)
MAX15090 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
MAX15090 toc12
PG ASSERTION DELAY
VIN = 12V
0
5
10
15
20
25
30
OVERCURRENT (%)
Maxim Integrated
6
MAX15090/MAX15090A
2.7V to 18V, 12A, Hot-Swap Solution
with Current Report Output
Bump Configuration
TOP VIEW
(BUMPS SIDE DOWN)
MAX15090
MAX15090A
1
2
3
4
5
6
7
A
ISENSE
VCC
IN
OUT
IN
GATE
CDLY
B
CB
GND
IN
OUT
IN
OUT
EN
C
GND
GND
IN
OUT
IN
OUT
FAULT
D
REG
UV
OV
OUT
IN
OUT
PG
+
WLP
(2.07mm x 3.53mm)
Bump Description
BUMP
NAME
A1
ISENSE
A2
VCC
A3, A5, B3,
B5, C3,
C5, D5
IN
A4, B4, B6,
C4, C6,
D4, D6
OUT
Maxim Integrated
FUNCTION
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.
Power-Supply Input. Connect VCC to a voltage between 2.7V and 18V. Connect a Schottky diode (or 6ω
resistor) from IN to VCC and a 1FF bypass capacitor to GND to guarantee full operation in the event VIN
collapses during a strong short from OUT to GND.
Supply Voltage Input. IN is connected to the drain of the internal 6mω 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.
Load Output. Source of the internal power MOSFET.
7
MAX15090/MAX15090A
2.7V to 18V, 12A, Hot-Swap Solution
with Current Report Output
Bump Description (continued)
BUMP
NAME
FUNCTION
A6
GATE
GATE of Internal MOSFET. During startup, a 5.7FA 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.
A7
CDLY
Enable Timer Input. Connect a capacitor between CDLY and GND to set a 1s/FF duration timeout
delay. The EN input has to be pulled low before the timeout delay elapses, to prevent internal MOSFET
shutdown after power-up.
B1
CB
B2, C1, C2
GND
Current-Limit Threshold Set. Connect a resistor from CB to GND to set the circuit-breaker threshold. Maximum
value of 40.2kω can be accepted for safe operation. Having the CB pin connected to GND sets the circuitbreaker threshold at 0A.
Ground
B7
EN
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.
C7
FAULT
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.
D1
REG
Internal Regulator Output. Bypass to ground with a 1FF capacitor. Do not power external circuitry using
the REG output (except a resistor > 50kω connected from REG to EN).
D2
UV
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.
D3
OV
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.
D7
PG
Power-Good Output. PG is an open-drain, active-high output. PG pulls low until the internal power
MOSFET is fully enhanced.
Detailed Description
Enable Logic and Undervoltage/
Overvoltage-Lockout Threshold
The MAX15090/MAX15090A ICs enable the output, as
shown in Table 1. The devices are ready to drive the output when the VCC supply rises above the VUVLO threshold. The devices turn on the output when VCC > VUVLO,
Maxim Integrated
VUV is high (VUV > 1.23V) and VOV is low (VOV < 1.23V).
The devices turn off the output when VUV falls below
(1.23V - VUV_HYS) or VOV rises above 1.23V. An external
resistive divider from IN to UV, OV, and ground provide
the flexibility to set the undervoltage/overvoltage-lockout
threshold to any desired level between VUVLO and 18V.
See Figure 1 and the Setting the Undervoltage Threshold
and Setting the Overvoltage Threshold sections.
8
MAX15090/MAX15090A
2.7V to 18V, 12A, Hot-Swap Solution
with Current Report Output
Table 1. Output Enable Truth Table
POWER SUPPLY
PRECISION ANALOG INPUTS
OUT
VCC
UV
OV
VCC > VUVLO
VUV > VUV_TH
VOV < VOV_TH
On
VCC < VUVLO
X
X
Off
X
VUV < (VUV_TH - VUV_HYS)
X
Off
X
X
VOV > VOV_TH
Off
X = Don’t care.
VUV_TH and VOV_TH = 1.23V (typ).
IN
An internal 50ms timer starts counting when the devices
enter the startup phase. The devices complete the startup phase and enter normal operation mode if the voltage
at OUT rises above the precharge threshold (0.9 x VIN)
and (VGATE - VOUT) > 3V. An open-drain power-good
output (PG) goes high-impedance 16ms after the startup
successfully completes.
MAX15090
MAX15090A
R1
UV
R2
1.23V
The thermal-protection circuit is always active and
the internal MOSFET immediately turned off when the
thermal-shutdown threshold condition is reached.
CONTROL
LOGIC
OV
VariableSpeed/BiLevel Fault Protection
R3
GND
Figure 1. Undervoltage/Overvoltage-Threshold Setting
Startup
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 pro­grammed by selecting the appropriate value of
RCB. During startup, a foldback current limit is active to
protect the internal MOSFET to operate within the SOA
(Figure 2).
Maxim Integrated
VariableSpeed/BiLevel fault protection incorporates comparators 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 MAX15090A enters
autoretry mode, while the MAX15090 latches off (see the
Autoretry and Latch-Off Fault Management section).
Enable Input (EN)
After a startup phase is successfully completed and
the power-good output asserted, the EN input has to
be pulled low (for at least 1ms) before the tDLY delay
elapses. If the EN input is not pulled low before the tDLY
elapses, then 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/FF duration timeout delay. If this
function in is not implemented, connect EN to GND for
proper operation.
9
MAX15090/MAX15090A
2.7V to 18V, 12A, Hot-Swap Solution
with Current Report Output
IINRUSH
RCB = 40.2kI
6A
RCB = 10kI
1.5A
1A
0.25A
2V
10V
VIN - VOUT
Figure 2. Startup Inrush Current Foldback Characteristics
SLOW COMPARATOR
TURN-OFF TIME
2.7ms
200µs
FAST COMPARATOR
200ns
0.6%
OVERCURRENT
30%
50%
OVERCURRENT OVERCURRENT
OUT CURRENT
Figure 3. VariableSpeed/BiLevel Response
Maxim Integrated
10
MAX15090/MAX15090A
2.7V to 18V, 12A, Hot-Swap Solution
with Current Report Output
Charge Pump
The devices also feature catastrophic short-circuit
protec­tion. 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.
During startup, the internal charge pump drives the GATE
of the MOSFET with a fixed 5.7FA current to enhance the
internal MOSFET with 10V/ms slew rate (typ). Connect an
external capacitor (CGATE) from GATE to GND to reduce
the output slew rate during startup. CGATE can be
calculated according to the following formula:
During a fault condition, the devices turn off the inter­nal
MOSFET, disconnecting the output from the input. The
MAX15090A enters autoretry mode and restarts after
a tRESTART time delay has elapsed. The MAX15090
latches off and remains off until the enable logic is cycled
off and on after a tRESTART delay. The delay prevents
the latch-off device to restart and operate with an unsafe
power-dissipation duty cycle.
An integrated charge pump provides the gate-drive voltage for the internal power MOSFET. The charge pump
generates the proper gate drive voltage above VIN to
fully enhance the internal power MOSFET and guarantee
low RON operation during normal state conditions.
CGATE = (IGATE x Dt)/DVGATE
where IGATE is 5.7FA (typ), Dt is the desired slew-rate
time, and DVGATE is the voltage at the gate of the internal
MOSFET at turn-on.
The slew rate of the OUT pin during startup can be
controlled by IGATE/CGATE under light-load driving
conditions, or by the limited inrush current and the external capacitive load, whichever is less.
(DVOUT/Dt) = ILIM/CLOAD
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:
ICB = RCB/3333.3
where ICB is in amps and RCB (the resistor between 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 overcurrent 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 40.2kω, which corresponds to a 12A
CB threshold setting. Programming the CB threshold to
a value higher than 12A could cause unsafe operating
conditions, resulting in damage to the devices.
Maxim Integrated
Autoretry and Latch-Off Fault Management
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.
Power-Good (PG) Delay
The devices feature an open-drain, power-good output
that asserts after a tPG delay, indicating that the OUT
voltage has reached (0.9 x VIN) voltage and (VGATE VOUT) > 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 1FF capacitor to ground for proper
operation.
Current Report Output (ISENSE)
The ISENSE pin is the output of an accurate currentsense amplifier and provides a source current that is proportional to the load current flowing into the main switch.
The factory-trimmed current ratio is set to 220FA/A. This
produces a scaled voltage by connecting a resistor
between ISENSE and ground. This voltage signal then
goes to an ADC and provides digitized information of the
current supplied to the powered system.
11
MAX15090/MAX15090A
2.7V to 18V, 12A, Hot-Swap Solution
with Current Report Output
Thermal Protection
where VIN is the desired turn-on voltage for the output
and VUV_TH is 1.23V. R1 and (R2 + R3) create a resistive
divider from IN to UV. During normal operating conditions, VUV must remain above its 1.23V (typ) threshold.
If VUV falls 100mV (VUV_HYS) below the threshold, the
internal MOSFET turns off, disconnecting the load from
the input.
IN to OUT Short-Circuit Protection
The devices also feature an independent overvoltageenable control (OV) for the internal MOSFET.
The devices enter a thermal-shutdown mode in the event
of overheating caused by excessive power dissipation
or high ambient temperature. When the junction tem­
perature exceeds TJ = +150NC (typ), the internal thermalprotection circuitry turns off the internal power MOSFET.
The devices recover from thermal-shutdown mode once
the junction temperature drops by 20NC (typ).
At startup, after all the input conditions are satisfied (UV,
OV, VUVLO), the devices immediately check for an IN to
OUT short-circuit fault. If VOUT is greater than 90% of
VIN, the internal MOSFET cannot be turned on so FAULT
is asserted and the MAX15090A enters autoretry mode in
3.2s, while the MAX15090 latches off.
If VOUT is lower than 90% of VIN but greater than 50%
of VIN, the internal MOSFET still cannot be turned on. No
fault is asserted and the MOSFET can turn on as soon as
VOUT is lower than 50% of VIN.
Applications Information
Setting the Undervoltage Threshold
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.
The internal MOSFET remains off as long as VCC < 2.5V
or VUV < VUV_TH. The undervoltage-lockout threshold is
pro­grammable using a resistive divider from IN to UV,
OV, and GND (Figure 1). When VCC is greater than 2.7V
and VUV exceeds the 1.23V (typ) threshold, the internal
MOSFET turns on and goes into normal operation. Use
the following equation to calculate the resistor values for
the desired undervoltage threshold:
 VIN
R1 
=
V
 UV_TH
Maxim Integrated
−

1 × (R2 + R3 )


Setting the Overvoltage Threshold
When VOV exceeds the 1.23V (typ) threshold, the internal
MOSFET turns off.
The overvoltage-lockout threshold is pro­
grammable
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
=
(R1 + R2 )  IN
 VOV_TH
−

1 × R3


where VIN is the desired turn-off voltage for the output
and VOV_TH is 1.23V. R1 and (R2 + R3) create a resistive
divider from IN to OV. During normal operating conditions, VOV must remain below its 1.23V (typ) threshold.
If VOV rises above the VOV_TH threshold, the internal
MOSFET turns off and disconnects the load from the
input.
Wafer-Level Packaging (WLP)
Applications Information
For the latest application details on WLP construction,
dimensions, tape carrier information, PCB techniques,
bump-pad layout, recommended reflow temperature
profile, as well as the latest information on reliability testing results, refer to Application Note 1891: Wafer-Level
Packaging (WLP) Applications Information, available at
www.maximintegrated.com/wlp.
12
MAX15090/MAX15090A
2.7V to 18V, 12A, Hot-Swap Solution
with Current Report Output
Functional Diagram
MPOW
IN
VCC
OUT
ILOAD /4545
IREF
MS1
CHARGE
PUMP
ILOAD
ISENSE
FAULT
MAX15090
MAX15090A
IGATE
GATE
CB_SLOW_COMP
IPD
UV
CONTROL
LOGIC
2 x ISLEW
1.23V
OV
TEMP
SENSE
VCC
LDO
REGULATOR
FAST_COMP
STARTUP
CONTROL AND
FOLDBACK
GATE
GATE_OK
REFERENCE
GENERATOR
PG
1.23V
0.9 x VIN
12µA
1.9µA
CB
CDLY
2V
DLY
CTRL
EN
Maxim Integrated
REG
GND
13
MAX15090/MAX15090A
2.7V to 18V, 12A, Hot-Swap Solution
with Current Report Output
Typical Application Circuit
12V
IN
RIN
OUT
TVS
GATE
CGATE
VCC
R1
CIN
UV
MAX15090
MAX15090A
CB
RCB
RPG
RFAULT
PG
REG
R2
DC-DC
REGULATOR
3.3V OUTPUT
FAULT
ISENSE
CREG
RISENSE
OV
A/D
CONVERTER
CDLY
EN
CCDLY
R3
GND
Chip Information
Package Information
Ordering 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.
PROCESS: BiCMOS
PART
TEMP
RANGE
PINPACKAGE
FAULT
MANAGEMENT
MAX15090EWI+
-40NC to
+85NC
28 WLP
Latched Off
MAX15090AEWI+
-40NC to
+85NC
28 WLP
Autoretry
PACKAGE
TYPE
PACKAGE
CODE
OUTLINE
NO.
LAND PATTERN
NO.
28 WLP
W282B3Z+1
21-0577
Refer to
Application note
1891
+Denotes a lead(Pb)-free/RoHS-compliant package.
Maxim Integrated
14
MAX15090/MAX15090A
2.7V to 18V, 12A, Hot-Swap Solution
with Current Report Output
Revision History
REVISION
NUMBER
REVISION
DATE
DESCRIPTION
PAGES
CHANGED
0
9/12
Initial release
—
1
12/12
Removed future product designation for the MAX15090A version
14
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 160 Rio Robles, San Jose, CA 95134 USA 1-408-601-1000
© 2012 Maxim Integrated Products, Inc.
15
Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc.