Maxim MAX5900LCETT-T -100v, sot23/tdfn, simple swapper hot-swap controller Datasheet

19-2077; Rev 5; 1/07
-100V, SOT23/TDFN, Simple Swapper
Hot-Swap Controllers
The MAX5900/MAX5901 are SOT23/TDFN hot-swap controllers that allow a circuit card to be safely hot-plugged
into a live backplane without causing a glitch on
the power-supply rail. These devices operate from -9V to
-100V and provide the simplest hot-swap solution by
eliminating all external components except an external
n-channel MOSFET.
The MAX5900/MAX5901 limit the inrush current to the
load and provide a circuit-breaker function for overcurrent
protection. During startup, the circuit-breaker function is
disabled and the MAX5900/MAX5901 limit the inrush current by gradually turning on the external MOSFET. Once
the external MOSFET is fully enhanced, the circuit-breaker function is enabled and the MAX5900/MAX5901 provide overcurrent protection by monitoring the voltage
drop across the external MOSFET’s on-resistance.
The MAX5900/MAX5901 include an undervoltage lockout (UVLO) function, ON/OFF control input, and a powergood status output, PGOOD (MAX5900) or PGOOD
(MAX5901). A built-in thermal shutdown feature is also
included to protect the external MOSFET in case of overheating.
The MAX5900/MAX5901 offer latched or autoretry fault
management and are available with 200mV, 300mV, or
400mV circuit-breaker thresholds. Both the MAX5900 and
MAX5901 are available in small SOT23 and TDFN packages, and are specified for the extended -40°C to +85°C
temperature range. For specific ordering information see
the Selector Guide at the end of the data sheet.
_________________________Applications
TelecomNo
Line
Cards Sense Resistor
Network Switches
♦ Requires
External
Network Routers
Servers
Base-Station Line
Cards
Typical Operating Circuits
50W ISOLATED
POWER SUPPLY
BACKPLANE CIRCUIT CARD
GND
Features
♦
♦
♦
♦
♦
♦
♦
♦
♦
♦
♦
♦
Wide -9V to -100V Operation
Requires No External Sense Resistor
Drives External N-Channel MOSFET
Limits Inrush Current
Circuit-Breaker Function
Less than 1mA Quiescent Current
ON/OFF Input Permits Load Power-Supply
Control and Sequencing
Adjustable Undervoltage Lockout
Power-Good Output with 100V Rating
Latching or Automatic Retry Fault Management
Thermal Shutdown Helps Protect the External
MOSFET
Space-Saving 6-Pin SOT23 and TDFN Packages
Ordering Information
PART
PINPACKAGE
TEMP RANGE
MAX5900_ _EUT+T* -40°C to +85°C 6 SOT23-6
MAX5900_ _ETT+T*
U6F-6
-40°C to +85°C 6 TDFN-EP** T633-2
MAX5901_ _EUT+T* -40°C to +85°C 6 SOT23-6
MAX5901_ _ETT+T*
PKG
CODE
U6F-6
-40°C to +85°C 6 TDFN-EP** T633-2
*For specific part numbers, see Selector Guide at end of data
sheet.
+Denotes lead-free package.
**EP = Exposed pad.
Pin Configurations
TOP VIEW
VEE 1
DRAIN 2
MAX5900
MAX5901
6
ON/OFF
5
PGOOD (PGOOD)
4
GND
HOT-SWAP CONTROLLER
V 1+
LUCENT
JWO50A1
MAX5900
GND
ON/OFF
VEE
-48V
FUSE
ON/OFF
PGOOD
DRAIN
GATE 3
SOT23
( ) ARE FOR MAX5901 ONLY.
GATE
V1-
IRF540NS
Pin Configurations continued at end of data sheet.
Typical Operating Circuits continued at end of data sheet.
Simple Swapper is a trademark of Maxim Integrated Products, Inc.
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
1
MAX5900/MAX5901
General Description
MAX5900/MAX5901
-100V, SOT23/TDFN, Simple Swapper
Hot-Swap Controllers
ABSOLUTE MAXIMUM RATINGS
Terminal Voltage (with respect to GND, unless otherwise noted)
VEE, DRAIN, PGOOD, PGOOD ............................-120V to +0.3V
ON/OFF to VEE .........................................................-0.3V to +4V
GATE to VEE ......................................................... -0.3V to +12V
Current into Any Pin............................................................±3mA
Continuous Power Dissipation (TA = +70°C)
6-Pin SOT23 (derate 9.1mW/°C above +70°C)...........727mW
6-Pin TDFN (derate 18.2mW/°C above +70°C) ........1454mW
Junction to Case Thermal Resistance, θJC (TDFN) ........8.5°C/W
Maximum Junction Temperature .....................................+150°C
Storage Temperature Range .............................-60°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
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.
ELECTRICAL CHARACTERISTICS
(VEE = -9V to -100V, GND = 0V, ON/OFF open circuit, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VEE = -48V
and TA = +25°C.) (Notes 1, 2)
PARAMETER
SYMBOL
Supply Voltage
VEE
Supply Current
IGND
CONDITIONS
Measured at GND
Load Voltage Slew-Rate
Magnitude
Default UVLO
VGS
SR
VUVLO
VGATE - VEE
Drain to VEE Resistance
ON/OFF Reference
Threshold
V
mA
1.3
11.6
VEE = -100V
8
10
11.6
V
VEE = -9V
6
7
4.5
10
17
V/ms
-34.5
-31.5
-28.5
V
| dVDRAIN/dt |, CLOAD = 10µF, VEE = -9V to -36V
|VEE| increasing
3.5
RON/OFF
20
RDVEE
VON/OFF
32
V
50
466
(VON/OFF - VEE) increasing
1.14
1.26
tON
150
300
ON/OFF Off Delay (Note 4)
tOFF
VGATE - VEE < 1V
1.38
mV
ms
ms
9
20
32
170
200
240
MAX590_ _BEUT
265
300
345
MAX590_ _CEUT
365
VDRAIN - VEE
Circuit-Breaker Delay
(Note 5)
tCB
(VDRAIN - VEE) > VCB
until (VGATE - VEE ) <
1V, 200mV overdrive
step
Restart Delay (Note 3)
tRS
After circuit-breaker event, MAX590_A_EUT only
400
455
CGATE = 1nF
1.5
3
CGATE = 4.7nF
2.5
4.5
CGATE = 10nF
150
4
6
300
500
_______________________________________________________________________________________
V
500
MAX590_ _AEUT
VCB
kΩ
kΩ
140
Start Delay (Note 3)
2
UNITS
-9
0.5
ON/OFF Hysteresis
Circuit-Breaker
Threshold
MAX
9.5
UVLO Hysteresis
ON/OFF Input Resistance
TYP
7.5
VEE = -36V to -72V
External Gate Drive
MIN
-100
mV
µs
ms
-100V, SOT23/TDFN, Simple Swapper
Hot-Swap Controllers
(VEE = -9V to -100V, GND = 0V, ON/OFF open circuit, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VEE = -48V
and TA = +25°C.) (Notes 1, 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
PGOOD (PGOOD)
Assertion Threshold
(Note 6)
VPG
VDRAIN - VEE; MAX590_A,
MAX590_L only
PGOOD (PGOOD)
Output Low Voltage
VOL
MAX5900, VPGOOD - VEE, IOL = 1mA;
MAX5901, VPGOOD - VEE, IOL = 1mA
0.6
1.65
V
Power-Good Output OpenDrain Leakage Current
IOH
VPGOOD - VEE = 100V (MAX5900);
VPGOOD - VEE = 100V (MAX5901)
0.2
10
µA
Thermal Shutdown
Temperature
TSD
Junction temperature
Thermal Shutdown
Hysteresis
THY
0.75 ✕ VCB
mV
+125
°C
15
°C
Note 1: All currents into device pins are positive, all currents out of device pins are negative, and all voltages are referenced to
GND, unless otherwise noted.
Note 2: All specifications are 100% tested at TA = +25°C. Specifications over -40°C to +85°C are guaranteed by characterization.
Note 3: This is the delay time from a valid on condition until VGS begins rising. Valid on conditions are: the device is not in undervoltage lockout; ON/OFF is not driven low; and the device is not in thermal shutdown.
Note 4: This is the delay from a valid low on ON/OFF until VGS falls. Pulses on ON/OFF less than tOFF are ignored, offering glitch
immunity.
Note 5: Guaranteed by design, not production tested.
Note 6: For a detailed description, see the Power-Good Output section.
Typical Operating Characteristics
(VEE = -48V, GND = 0V, and TA = +25°C, unless otherwise noted. See Figure 6 for test circuits.)
100kΩ FROM ON/OFF TO GND
1.0
VEE = -75V
0.85
0.80
0.8
VEE = -48V
VUVLO (V)
IEE (mA)
0.9
MAX5900/1 toc02
0.90
MAX5900/01 toc01
1.1
SUPPLY CURRENT (mA)
DEFAULT UNDERVOLTAGE LOCKOUT
vs. TEMPERATURE
SUPPLY CURRENT vs. TEMPERATURE
0.75
0.70
VEE = -12V
0.7
-100
-80
-60
-40
INPUT VOLTAGE (V)
-20
0
INCREASING |VEE|
-35.5
-36.5
-37.5
0.60
0.5
DECREASING |VEE|
-33.5
-34.5
0.65
0.6
-25.5
-26.5
-27.5
-28.5
-29.5
-30.5
-31.5
-32.5
MAX9500/01 toc03
SUPPLY CURRENT
vs. INPUT VOLTAGE
0.55
-50
-25
0
25
50
75
TEMPERATURE (°C)
100
125
-50
-25
0
25
50
75
100
125
TEMPERATURE (°C)
_______________________________________________________________________________________
3
MAX5900/MAX5901
ELECTRICAL CHARACTERISTICS (continued)
Typical Operating Characteristics (continued)
(VEE = -48V, GND = 0V, and TA = +25°C, unless otherwise noted. See Figure 6 for test circuits.)
GATE DRIVE VOLTAGE
vs. INPUT VOLTAGE
RESTART DELAY
vs. TEMPERATURE
400
10.0
A
0
350
tRS (ms)
9.5
9.0
8.5
MAX5900/01 toc06
MAX5900/01 toc05
10.5
STARTUP WAVEFORMS
(RL = 90Ω, CL = 100µF)
450
MAX5900/1 toc04
11.0
0
B
0
C
300
250
8.0
0
200
7.5
7.0
D
150
-80
-60
-40
-20
0
-50
-25
0
INPUT VOLTAGE (V)
50
75
100
125
A: VGS, 5V/div
B: IIN, 1A/div
TEMPERATURE (°C)
STARTUP WAVEFORMS
(RL = OPEN, CL = 10µF)
MAX5900/1 toc08
A
0
0
0
B
0
B
0
B
0
C
0
C
0
C
D
0
D
0
D
5ms/div
A: VGS, 10V/div
B: IIN, 1A/div
CIRCUIT-BREAKER EVENT
(CGATE = 1000pF, VOVERDRIVE = 20mV)
B
0
B
0
C
0
C
0
SLEW RATE vs. VEE
TA = +120°C
11
SLEW RATE (V/ms)
A
0
C: VOUT, 50V/div
D: PGOOD, 50V/div
12
MAX5900/1 toc11
0
A: VGS, 10V/div
B: IIN, 1A/div
C: VOUT, 50V/div
D: PGOOD, 50V/div
CIRCUIT-BREAKER EVENT
(CGATE = 1000pF, VOVERDRIVE = 200mV)
MAX5900/1 toc10
A
5ms/div
5ms/div
C: VOUT, 50V/div
D: PGOOD, 50V/div
C: VEE, 50V/div
D: VDRAIN, 40V/div
A
0
A: VGS, 10V/div
B: IIN, 200mA/div
40ms/div
STARTUP WAVEFORMS
(RL = 40Ω, CL = 100µF)
STARTUP WAVEFORMS
(RL = 40Ω, CL = 10µF)
MAX5900/1 toc07
A
25
MAX5900/1 toc09
-100
MAX5900/01 toc12
VGS (V)
MAX5900/MAX5901
-100V, SOT23/TDFN, Simple Swapper
Hot-Swap Controllers
10
9
TA = +25°C
8
TA = -40°C
7
6
2µs/div
D: PGOOD, 50V/div
B: VDS, 500mV/div
4
C: VGS, 10V/div
2µs/div
D: PGOOD, 50V/div
B: VDS, 500mV/div
C: VGS, 10V/div
-100
-80
-60
-40
VEE (V)
_______________________________________________________________________________________
-20
0
-100V, SOT23/TDFN, Simple Swapper
Hot-Swap Controllers
PIN
MAX5900
MAX5901
1
1
NAME
VEE
FUNCTION
Negative Supply Voltage Input and External n-Channel MOSFET Source
Connection
2
2
DRAIN
Drain Sense Input for External n-Channel MOSFET. Connect DRAIN as close as
possible to the MOSFET’s drain and use wide circuit traces to assure good
thermal coupling between the MAX5900/MAX5901 and the MOSFET (see the
Layout Guidelines section).
3
3
GATE
Gate Drive Output for External n-Channel MOSFET
4
4
GND
Ground Connection.
5
—
PGOOD
Power-Good Output. PGOOD is an n-channel, open-drain, active-low output,
referenced to VEE.
—
5
PGOOD
Power-Good Output. PGOOD is an n-channel, open-drain, active-high output,
referenced to VEE.
ON/OFF Control Input. ON/OFF is referenced to VEE. Drive ON/OFF above 1.38V
or leave unconnected to enable the device. Drive ON/OFF below 1V to disable
the device. ON/OFF is also used to adjust the UVLO threshold. See the Undervoltage Lockout section in the Applications Information. Internally clamped to
nominally 3V through a 1kΩ resistor (see Figure 1).
6
6
ON/OFF
—
—
EP
Exposed Pad (TDFN only). Connect to VEE.
Detailed Description
The MAX5900/MAX5901 are integrated hot-swap controller ICs contained in 6-pin SOT23/TDFN packages.
They allow a board to be safely hot plugged into a live
backplane without causing a glitch on the power-supply rail. They are well suited for -48V telecom power
systems, allowing a cost-effective, simple, and compact design. The MAX5900/MAX5901 operate from -9V
to -100V to cover the standard telecom voltage range,
and to serve more generalized applications. These
devices require only an external n-channel power MOSFET to provide hot-swap control. Figure 1 shows a
functional diagram of the MAX5900/MAX5901.
The MAX5900/MAX5901 control an external n-channel
power MOSFET placed in the negative power-supply
pathway. When power is first applied, the MAX5900/
MAX5901 keep the MOSFET turned off. The MAX5900/
MAX5901 hold the MOSFET off indefinitely if ON/OFF is
held low, if the supply voltage is below the undervoltage lockout level, or if the die temperature exceeds
+125°C. If none of these conditions exist for 300ms
(typ), the MAX5900/MAX5901 begin to gradually turn
on the MOSFET. During this turn-on phase, the
MAX5900/MAX5901 slowly enhance the MOSFET,
MAX5900
MAX5901
GND
828kΩ*
ON/OFF
CONTROL
LOGIC
1kΩ*
PGOOD
(PGOOD)
34.5kΩ*
3V
N
VEE
VEE
VEE
466kΩ*
GATE
DRAIN
( ) ARE FOR THE MAX5901 ONLY.
*RELATIVE TOLERANCE ±1%, ABSOLUTE TOLERANCE ±20% TYPICAL.
Figure 1. Functional Diagram
_______________________________________________________________________________________
5
MAX5900/MAX5901
Pin Description
MAX5900/MAX5901
-100V, SOT23/TDFN, Simple Swapper
Hot-Swap Controllers
allowing the voltage on the load, i.e. the drain of the
MOSFET, to fall no faster than 10V/ms (typ). The inrush
current to the load is thus limited to a level proportional
to the load capacitance, and the constant load voltage
slew rate. After the MOSFET is fully enhanced, and the
load voltage is settled to its final value, the MAX5900A/
MAX5901A and MAX5900L/MAX5901L monitor the voltage drop from the MOSFET’s drain-to-source (VDS). If
the voltage drop exceeds 75% of the circuit-breaker
threshold the MAX5900A/MAX5901A or MAX5900L/
MAX5901L turn off the MOSFET, disconnecting the
load immediately. Because the circuit-breaker function
is not activated until the MOSFET is fully enhanced, it
takes approximately 10ms for the MAX5900A/
MAX5901A or MAX5900L/MAX5901L to react to an output short circuit at startup. If no circuit-breaker fault
exists, the power-good output is asserted. Then, if any
of four conditions exist, the power-good output
deasserts and the MOSFET is turned off . The four conditions are: the voltage across the MOSFET exceeds
the circuit-breaker threshold; the supply voltage magnitude falls below the undervoltage lockout level; the die
temperature exceeds +125°C; or ON/OFF is forced low.
After a circuit-breaker fault, the MAX5900L/MAX5901L
keep the MOSFET off until the power is cycled, or the
part is reset by toggling ON/OFF low for at least 20ms
(typ). After a circuit-breaker fault, the MAX5900A/
MAX5901A automatically restart in 300ms (typ). All versions automatically restart after a thermal fault, or an
undervoltage shutdown, if the fault condition goes away
for at least 300ms (typ).
ON/OFF offers external control of the MAX5900/
MAX5901, facilitating power-supply sequencing, and
may also be used to change the UVLO level. UVLO
keeps the external MOSFET switched off as long as the
magnitude of the input voltage is less than a desired
level.
A power-good output, PGOOD (MAX5900) or PGOOD
(MAX5901), asserts when the external MOSFET is fully
enhanced and the drain-source voltage is at least 25%
below the circuit-breaker threshold. PGOOD and
PGOOD are open-drain outputs referenced to VEE, and
can withstand up to 100V above VEE.
A thermal shutdown feature protects the external MOSFET by turning it off if the die temperature of the
MAX5900/MAX5901 exceeds +125°C. The MAX5900/
MAX5901 must be in good thermal contact with the
external MOSFET. See the Layout Guidelines section in
the Applications Information.
circuit-breaker function is enabled after the MOSFET is
fully enhanced. Three threshold voltage options are
available—200mV, 300mV, and 400mV. One version is
available with no circuit-breaker function. circuit-breaker fault management for the MAX5900/MAX5901 is
offered with two different configurations—latched and
automatic retry.
Latched Circuit Breaker
After a circuit-breaker trip event, the latched versions
(MAX5900L/MAX5901L) drive GATE to VEE, turning off
the external MOSFET, and PGOOD (PGOOD) is
deasserted. A latched-off condition needs to be reset
by toggling ON/OFF low for at least 20ms, or by cycling
the power supply, VEE.
Automatic Retry Circuit Breaker
After a circuit-breaker trip event, the automatic retry
versions (MAX5900A/MAX5901A) drive GATE to VEE,
turning off the external MOSFET, and PGOOD
(PGOOD) is deasserted. If the start conditions are met
for a full 300ms (tRS) the start sequence is initiated. The
start conditions are: the device is not in UVLO; ON/OFF
is not driven low; and the device is not in thermal shutdown.
No Circuit Breaker
For the versions without a circuit-breaker MAX5900N
(MAX5901N), PGOOD (PGOOD) is asserted when the
MOSFET is fully enhanced. Once powered up, the
MAX5900N/MAX5901N ignore the MOSFET drain-tosource voltage (VDS) for applications where a circuitbreaker function is not desired.
Applications Information
ON/OFF Control Input
The ON/OFF control input provides three hot-swap
functions: external ON/OFF control; setting of the UVLO
level; and resetting after a circuit-breaker event has
caused the MAX5900L/MAX5901L to turn off the external MOSFET. Pulling ON/OFF to VEE for at least 20ms
(t OFF) forces the MAX5900/MAX5901 to turn off the
external MOSFET (see Figure 2 for a circuit example).
To reset the MAX5900L/MAX5901L after a circuitbreaker event, toggle ON/OFF to VEE for at least 20ms
(tOFF).
ON/OFF can be used to sequence power supplies.
Connecting a capacitor from ON/OFF to VEE will delay
the rise of ON/OFF proportional to the capacitance and
input impedance of ON/OFF, typically 32kΩ (Figure 3).
A circuit-breaker function monitors the voltage across
the external MOSFET, VDS, and turns off the MOSFET if
VDS exceeds the circuit-breaker threshold, VCB. The
6
_______________________________________________________________________________________
-100V, SOT23/TDFN, Simple Swapper
Hot-Swap Controllers
GND
OPTIONAL
MAX5900
MAX5901
R2
47kΩ
ON/OFF
GND
ON/OFF
R1
3kΩ
DGND
voltage spikes, as well as preventing accidental
resetting of the circuit-breaker latch (MAX5900L/
MAX5901L).
VEE
-48V
Figure 2. Programmed -20V Lockout With Optional
Optocoupler On/Off Control
Thermal Shutdown
A thermal shutdown feature helps protect the external
MOSFET. If the die temperature of the MAX5900/
MAX5901 exceeds +125°C, the MOSFET is turned off.
For accurate performance, the MAX5900/MAX5901
must be in close thermal contact with the external
MOSFET (see the Layout Guidelines section). Due to
the low power dissipation of the MAX5900/MAX5901, its
junction temperature will typically be within a few
degrees of the MOSFET. All versions of the MAX5900/
MAX5901 automatically restart from a temperature fault
when the junction temperature drops below +110°C.
HOT-SWAP CONTROLLER #1
GND
MAX5900
MAX5901
GND
ON/OFF
C
VEE
HOT-SWAP CONTROLLER #2
MAX5900
MAX5901
GND
ON/OFF
2C
VEE
VEE
Figure 3. Power-Supply Sequencing
Turn-On and Turn-Off Delays
After power is applied, or ON/OFF is released, there is
a 300ms delay (tON) before the gate ramp is started.
This delay is also the automatic restart time delay.
In the event of a circuit-breaker condition or an overtemperature fault condition, the turn-off delay is less
than 2µs. An undervoltage condition must exist for at
least 20ms (tOFF) before the MAX5900/MAX5901 turn
off the external MOSFET. ON/OFF must be held low for
at least 20ms (tOFF) before the MAX5900/MAX5901 turn
off the external MOSFET. Turn-off delay minimizes spurious shutdowns due to noisy signals or momentary
Undervoltage Lockout
The MAX5900/MAX5901 turn off the external MOSFET if
the magnitude of the input voltage is below the level set
by ON/OFF for longer than 20ms (tOFF). If ON/OFF is
left unconnected, the lockout voltage (VUVLO) defaults
to -31.5V. VUVLO may also be set to any value within
the power-supply range by using external resistors. To
set the lockout voltage to a value between -9V and
-100V, use a resistor-divider connected between GND
and VEE, with the center node of the divider connected
to ON/OFF. For example, use a 3kΩ resistor (R1 in
Figure 2) from ON/OFF to VEE and calculate the other
resistor, R2, using:
⎛V
⎞
R2 = R1 × ⎜ UVLO − 1⎟
⎝ 1.26
⎠
where V UVLO is the desired lockout voltage, and
VON/OFF is the ON/OFF reference threshold specified in
the Electrical Characteristics table (typically 1.26V).
Figure 2 shows an example circuit with VUVLO set for
-20V. To defeat the UVLO, simply connect a single 100kΩ
resistor between ON/OFF and GND, as shown in Figure 4.
HOT-SWAP CONTROLLER
GND
100kΩ
MAX5900
MAX5901
GND
ON/OFF
VEE
-48V
Figure 4. Defeating Undervoltage Lockout
_______________________________________________________________________________________
7
MAX5900/MAX5901
HOT-SWAP CONTROLLER
MAX5900/MAX5901
-100V, SOT23/TDFN, Simple Swapper
Hot-Swap Controllers
Power-Good Output
The power-good output, PGOOD (PGOOD), is opendrain and asserts when the external MOSFET is fully
enhanced and VDS is less than VPG (75% of the circuitbreaker threshold, VCB). For versions without the circuitbreaker function (MAX5900N/MAX5901N), PGOOD
(PGOOD) asserts when the external MOSFET is fully
enhanced.
PGOOD (PGOOD) deasserts within 2µs when a circuitbreaker event occurs or if the die temperature exceeds
+125°C. PGOOD (PGOOD) deasserts if |VEE| < |VUVLO|
for longer than 20ms or ON/OFF is held low for longer
than 20ms.
The MAX5900 PGOOD is active-low and the MAX5901
PGOOD is active-high. Both are open-drain N-channel
MOSFETs with their sources connected to VEE, and can
withstand up to 100V.
breaker threshold allows the circuit to operate under
worst-case conditions without causing a circuit-breaker
fault, but the circuit-breaker function will still operate if a
short-circuit or gross overcurrent condition occurs. See
Table 1 for MOSFET suggestions. The MAX5900N/
MAX5901N have no circuit-breaker function. For these
parts choose an external MOSFET that meets the load
requirements.
Determining Inrush Current
Determining a circuit’s inrush current is necessary to
help choose the proper MOSFET. The MAX5900/
MAX5901 regulate the inrush current by means of controlling the load voltage slew rate, but inrush current is
also a function of load capacitance. Determine inrush
current using:
I=C
Selecting a Circuit-Breaker Threshold
The MAX5900A/MAX5901A and the MAX5900L/
MAX5901L offer a circuit-breaker function to protect the
external MOSFET and the load from the potentially
damaging effects of excessive current. As load current
flows through the external MOSFET, a voltage, VDS, is
generated from drain to source due to the MOSFET’s
on-resistance RDS(ON). The MAX5900A/MAX5901A and
MAX5900L/MAX5901L monitor VDS when the external
MOSFET is fully enhanced. If VDS exceeds the circuitbreaker threshold, the external MOSFET is turned off
and PGOOD (PGOOD) is deasserted.
To accommodate different MOSFETs and different load
currents, the MAX5900/MAX5901 are available with circuit-breaker threshold voltages of 200mV, 300mV, and
400mV.
The circuit-breaker function is intended to disconnect
the load if a gross overcurrent or short-circuit condition
occurs. For calculating the circuit-breaker threshold,
use the MOSFET’s RON at the worst possible operating
condition, and add a 25% overcurrent margin to the
maximum circuit current. For instance, if a MOSFET has
an RON of 0.06Ω at TA = +25°C, and a normalized onresistance factor of 1.75 at T A = +130°C (from the
MOSFET data sheet), the RON used for calculation is
the product of these two numbers, or (0.06Ω) x (1.75) =
0.105Ω. Then, if the maximum current is expected to be
2A, using a 25% margin, the current for calculation is
(2A) x (1.25) = 2.5A. The resulting minimum circuitbreaker threshold is then the product of these two
results, or (0.105Ω) x (2.5A) = 0.263V. The next highest
minimum available threshold is 0.265V of the
MAX590_ _BEUT, which is an ideal choice given these
parameters. Using this method to choose a circuit8
dV
= C × SR
dt
where C is the load capacitance, and SR is the
MAX5900/MAX5901 Load Voltage Slew-Rate
Magnitude from the Electrical Characteristics table. For
example, assuming a load capacitance of 100µF, and
using the typical value of 10V/ms for the slew rate, the
inrush current is 1A typical.
If the maximum possible Load Voltage Slew Rate is
used, the maximum inrush current calculates to 1.7A.
Choose a MOSFET with a maximum pulsed current
specification that exceeds the maximum inrush current.
Suggested External MOSFETs
SUGGESTED
EXTERNAL
MOSFET
SUGGESTED
MAXIM PART
0.25
IRFL110
MAX590_ _CEUT
0.5
IRFL4310
MAX590_ _BEUT
1
IRFR3910
MAX590_ _CEUT
2
IRF540NS
MAX590_ _BEUT
3
IRF1310NS
MAX590_ _BEUT
4
IRF1310NS
MAX590_ _CEUT
MAXIMUM
ILOAD (A)
VIN = -9V to -90V
_______________________________________________________________________________________
-100V, SOT23/TDFN, Simple Swapper
Hot-Swap Controllers
GROUND
U1
SOT23-6
MAX5900/MAX5901
POWER IN
M1
SOT-223
S D G
POWER
OUT
Chip Information
TRANSISTOR COUNT: 678
PROCESS: BiCMOS
Figure 5. Circuit Board Layout Example
GND
100kΩ
VIN
GND
100µF
+
MAX5900
V
-
ON/OFF MAX5901 PGOOD
(PGOOD)
VEE
GATE
VIN
+
V
-
DRAIN
VEE
(a) SUPPLY CURRENT
50kΩ
MAX5900
V
ON/OFF MAX5901 PGOOD
(PGOOD)
GATE
DRAIN
(b) VUVLO
GND
GND
100kΩ
+
VIN
-
48V
MAX5900
V
ON/OFF MAX5901 PGOOD
(PGOOD)
VEE
GATE
+
-
MAX5900A
ON/OFF MAX5901A PGOOD
(PGOOD)
VEE
GATE
DRAIN
V
DRAIN
SCOPE
SCOPE
50kΩ
(c) GATE DRIVE VOLTAGE
(d) RETRY TIMEOUT
GND
GND
48V
+
50kΩ
MAX5900
ON/OFF MAX5901 PGOOD
(PGOOD)
-
VEE
GATE
RL
50kΩ
CL
48V
SCOPE
+
-
MAX5900
ON/OFF MAX5901 PGOOD
(PGOOD)
VEE
DRAIN
GATE
SCOPE
DRAIN
SCOPE SCOPE
SCOPE
SCOPE
SCOPE
SCOPE
(e) TURN-ON WAVEFORMS
50kΩ
(f) CIRCUIT-BREAKER EVENT
Figure 6. Test Circuits
_______________________________________________________________________________________
9
MAX5900/MAX5901
Layout Guidelines
Good thermal contact between the MAX5900/
MAX5901 and the external MOSFET is essential for the
thermal shutdown feature to operate effectively. Place
the MAX5900/MAX5901 as close as possible to the
drain of the external MOSFET, and use wide circuit
board traces for good heat transfer. See Figure 5 for an
example of a PC board layout.
-100V, SOT23/TDFN, Simple Swapper
Hot-Swap Controllers
MAX5900/MAX5901
Selector Guide
SOT23
CIRCUIT-BREAKER
FUNCTION
CIRCUIT-BREAKER
THRESHOLD
(mV)
POWER-GOOD
OUTPUT LOGIC
TOP MARK
MAX5900NNEUT+T
None
None
Active-Low
AAQV
MAX5900AAEUT+T
Autoretry
200
Active-Low
AAQJ
MAX5900ABEUT+T
Autoretry
300
Active-Low
AAQK
MAX5900ACEUT+T
Autoretry
400
Active-Low
AAQL
MAX5900LAEUT+T
Latched
200
Active-Low
AAQM
MAX5900LBEUT+T
Latched
300
Active-Low
AAQN
MAX5900LCEUT+T
Latched
400
Active-Low
AAQO
MAX5901NNEUT+T
None
None
Active-High
AAQW
MAX5901AAEUT+T
Autoretry
200
Active-High
AAQP
MAX5901ABEUT+T
Autoretry
300
Active-High
AAQQ
MAX5901ACEUT+T
Autoretry
400
Active-High
AAQR
MAX5901LAEUT+T
Latched
200
Active-High
AAQS
MAX5901LBEUT+T
Latched
300
Active-High
AAQT
MAX5901LCEUT+T
Latched
400
Active-High
AAQU
PART
TDFN
CIRCUIT-BREAKER
FUNCTION
CIRCUIT-BREAKER
THRESHOLD
(mV)
POWER-GOOD
OUTPUT LOGIC
MAX5900NNETT+T
None
None
Active-Low
AJT
MAX5900AAETT+T
Autoretry
200
Active-Low
AJU
MAX5900ABETT+T
Autoretry
300
Active-Low
AJV
MAX5900ACETT+T
Autoretry
400
Active-Low
AJW
MAX5900LAETT+T
Latched
200
Active-Low
AJX
MAX5900LBETT+T
Latched
300
Active-Low
AJY
MAX5900LCETT+T
Latched
400
Active-Low
AJZ
MAX5901NNETT+T
None
None
Active-High
AKA
MAX5901AAETT+T
Autoretry
200
Active-High
AKB
PART
MAX5901ABETT+T
Autoretry
300
Active-High
AKC
MAX5901ACETT+T
Autoretry
400
Active-High
AKD
MAX5901LAETT+T
Latched
200
Active-High
AKE
MAX5901LBETT+T
Latched
300
Active-High
AKF
MAX5901LCETT+T
Latched
400
Active-High
AKG
+Denotes lead-free package.
10
TOP MARK
______________________________________________________________________________________
-100V, SOT23/TDFN, Simple Swapper
Hot-Swap Controllers
BACKPLANE
50W ISOLATED
POWER SUPPLY
CIRCUIT CARD
GND
HOT-SWAP CONTROLLER
V+
MAX5901
GND
ON/OFF
VEE
1MΩ
PGOOD
MAX5003*
INDIV
DRAIN
39kΩ
GATE
GND
-48V
IR540NS
FUSE
*MAX5003 IS A 110V PWM CONTROLLER.
Pin Configurations (continued)
TOP VIEW
VEE
1
DRAIN
2
GATE
3
MAX5900
MAX5901
6
ON/OFF
5
PGOOD (PGOOD)
4
GND
* EXPOSED PAD
TDFN
3mm x 3mm
( ) ARE FOR MAX5901 ONLY.
* EXPOSED PAD CONNECTED TO VEE.
______________________________________________________________________________________
11
MAX5900/MAX5901
Typical Operating Circuits (continued)
Package Information
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages.)
6LSOT.EPS
MAX5900/MAX5901
-100V, SOT23/TDFN, Simple Swapper
Hot-Swap Controllers
12
______________________________________________________________________________________
-100V, SOT23/TDFN, Simple Swapper
Hot-Swap Controllers
6, 8, &10L, DFN THIN.EPS
PACKAGE OUTLINE, 6,8,10 & 14L,
TDFN, EXPOSED PAD, 3x3x0.80 mm
21-0137
H
1
2
______________________________________________________________________________________
13
MAX5900/MAX5901
Package Information (continued)
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages.)
MAX5900/MAX5901
-100V, SOT23/TDFN, Simple Swapper
Hot-Swap Controllers
Package Information (continued)
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages.)
COMMON DIMENSIONS
PACKAGE VARIATIONS
SYMBOL
MIN.
MAX.
PKG. CODE
N
D2
E2
e
JEDEC SPEC
b
A
0.70
0.80
T633-1
6
1.50±0.10
2.30±0.10
0.95 BSC
MO229 / WEEA
0.40±0.05
1.90 REF
D
2.90
3.10
T633-2
6
1.50±0.10
2.30±0.10
0.95 BSC
MO229 / WEEA
0.40±0.05
1.90 REF
[(N/2)-1] x e
E
2.90
3.10
T833-1
8
1.50±0.10
2.30±0.10
0.65 BSC
MO229 / WEEC
0.30±0.05
1.95 REF
A1
0.00
0.05
T833-2
8
1.50±0.10
2.30±0.10
0.65 BSC
MO229 / WEEC
0.30±0.05
1.95 REF
L
0.20
0.40
1.95 REF
T833-3
8
1.50±0.10
2.30±0.10
0.65 BSC
MO229 / WEEC
0.30±0.05
k
0.25 MIN.
T1033-1
10
1.50±0.10
2.30±0.10
0.50 BSC
MO229 / WEED-3
0.25±0.05
2.00 REF
A2
0.20 REF.
T1033-2
10
1.50±0.10
2.30±0.10
0.50 BSC
MO229 / WEED-3
0.25±0.05
2.00 REF
T1433-1
14
1.70±0.10
2.30±0.10
0.40 BSC
----
0.20±0.05
2.40 REF
T1433-2
14
1.70±0.10
2.30±0.10
0.40 BSC
----
0.20±0.05
2.40 REF
PACKAGE OUTLINE, 6,8,10 & 14L,
TDFN, EXPOSED PAD, 3x3x0.80 mm
21-0137
-DRAWING NOT TO SCALE-
H
2
2
Revision History
Pages changed at Rev 5: 1–4, 10, 12–14
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
14 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2007 Maxim Integrated Products
is a registered trademark of Maxim Integrated Products, Inc.
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