19-4619; Rev 2; 5/09
12V Hot-Plug Switch
General Description
The DS4560 is a self-contained hot-plug switch intend-
ed to be used on +12V power buses to limit through
current and to control the power-up output-voltage
ramp. The device contains an on-board 25mΩ n-chan-
nel power MOSFET that is actively closed-loop con-
trolled to ensure that an adjustable current limit is not
exceeded. The maximum allowable current through the
device is determined by an external resistor connected
to the ILIM pin.
The DS4560 also contains the ability to control the
power-up output-voltage ramp. A capacitor connected
to the VRAMP pin sets the desired voltage ramp rate.
The output voltage is unconditionally clamped to keep
input overvoltage stresses from harming the load. The
DS4560 also contains an adjustable power-up timer. A
capacitor connected to the TIMER pin determines how
long after power-on reset the DS4560 should wait
before starting to apply power to the load. The TIMER
pin can also be driven with a digital logic output to cre-
ate a device-enable function.
The DS4560 contains an on-board temperature sensor
with hysteresis. If operating conditions cause the
device to exceed an internal thermal limit, the DS4560
either unconditionally shuts down and latches off await-
ing a power-on reset (DS4560S-LO), or it waits until the
device has cooled by the hysteresis amount and then
restarts (DS4560S-AR).
♦
On-Board 25mΩ Power MOSFET
♦
Adjustable Short-Circuit Current and Overload
Current Limit
♦
Adjustable Output-Voltage Slew Rate
♦
Adjustable Power-Up Timer with External Enable
Capability
♦
Output Overvoltage Limiting
♦
On-Board Thermal Protection
♦
On-Board Charge Pump
♦
Latchoff and Autoretry Versions Available
♦
9.0V to 13.2V Supply Operation
♦
8-Pin SO (150 mils) Pb-Free Package
♦
UL Certification Record E211395
Features
DS4560
Pin Configuration
TOP VIEW
GND
VRAMP
TIMER
ILIM
1
2
3
4
+
DS4560
8
7
6
5
V
CC
LOAD
LOAD
LOAD
Applications
RAID/Hard Drives
Servers/Routers
PCI/PCI Express
®
InfiniBand
SM
Base Stations
SO (150 mils)
Ordering Information
PART
DS4560S-LO+
DS4560S-LO+T
DS4560S-AR+
DS4560S-AR+T
THERMAL
SHUTDOWN
Latchoff
Latchoff
Autoretry
Autoretry
PIN-PACKAGE
8 SO
8 SO
8 SO
8 SO
PIN
1
2
3
4
5, 6, 7
8
NAME
GND
VRAMP
TIMER
ILIM
LOAD
V
CC
Pin Description
FUNCTION
Ground. This is also a heat sink for the
device.
Output-Voltage Ramp Adjustment
Power-Up Timer/Enable
Current-Limit Adjustment
Output Load Connection (MOSFET Source)
Input Supply Voltage (MOSFET Drain)
+Denotes
a lead(Pb)-free/RoHS-compliant package.
T = Tape and reel.
PCI Express is a registered trademark of PCI-SIG Corp.
InfiniBand is a trademark and service mark of the InfiniBand Trade Association.
________________________________________________________________
Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
12V Hot-Plug Switch
DS4560
ABSOLUTE MAXIMUM RATINGS
Voltage Range on V
CC
and LOAD Relative to GND
Continuous .........................................................-0.3V to +18V
1ms Maximum ....................................................-0.3V to +22V
Voltage Range on ILIM and VRAMP
Relative to GND.....................................-0.3V to (V
CC
+ 0.3V),
but not to exceed +18V
Voltage Range on TIMER Relative to GND ...........-0.3V to +5.0V
Drain Current
Continuous ...........................................................................4A
Peak ...................................................................................15A
Operating Junction Temperature Range ...........-40°C to +135°C
Storage Temperature Range .............................-55°C to +135°C
Soldering Temperature...........................Refer to the IPC/JEDEC
J-STD-020 Specification.
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.
RECOMMENDED OPERATING CONDITIONS
(T
J
= -40°C to +135°C.)
PARAMETER
Supply Voltage
R
ILIM
Value
C
VRAMP
Value
C
TIMER
Value
TIMER Turn-On Voltage
TIMER Turn-Off Voltage
SYMBOL
V
CC
R
ILIM
C
VRAMP
C
TIMER
V
ON
V
OFF
(Notes 1, 2)
CONDITIONS
MIN
9.0
20
0.04
0.04
2.6
-0.3
TYP
MAX
13.2
400
5.00
5.00
5
+2.0
μF
μF
V
V
UNITS
V
ELECTRICAL CHARACTERISTICS
(V
CC
= +12V, T
J
= +25°C, unless otherwise noted.)
PARAMETER
Supply Current
UVLO Rising
UVLO Falling
UVLO Hysteresis
On-Resistance
MOSFET Output Capacitance
LOAD Voltage During Off State
Delay Time from Enable to
Beginning of Conduction
Gate-Charging Time from
Conduction to 90% of V
OUT
Shutdown Junction Temperature
Thermal Hysteresis
TIMER Charging Current
Overvoltage Clamp
SYMBOL
I
CC
V
UVLOR
V
UVLOF
V
UVLOH
R
ON
C
OUT
V
LOFF
t
POND
t
GCT
T
SHDN
T
HYS
I
TIMER
V
OVC
(Note 4)
C
VRAMP
= 1μF
C
VRAMP
= 1μF, C
LOAD
= 1000μF
(Note 5)
(Note 5)
70
13.5
48
120
5
66
135
40
80
15.0
92
16.5
80
150
(Note 3)
7.5
6.5
CONDITIONS
MIN
TYP
1.1
8.0
7.0
1
25
500
200
32
MAX
2.00
8.5
7.5
UNITS
mA
V
V
V
m
pF
mV
ms
ms
°C
°C
μA
V
2
_______________________________________________________________________________________
12V Hot-Plug Switch
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= +12V, T
J
= +25°C, unless otherwise noted.)
PARAMETER
Short-Circuit Limit
Overload Limit
LOAD Voltage Slew Rate
VRAMP Charging Current
SYMBOL
I
SCL
I
OVL
SR
LOAD
I
VRAMP
R
ILIM
= 56
R
ILIM
= 56
CONDITIONS
(Note 6)
(Note 7)
MIN
2.0
3.5
0.13
70
TYP
2.5
4.4
0.15
80
MAX
3.0
5.9
0.18
92
UNITS
A
A
V/ms
μA
DS4560
C
VRAMP
= 1μF
Note 1:
Note 2:
Note 3:
Note 4:
Note 5:
Note 6:
Note 7:
All voltages are referenced to ground. Currents entering the IC are specified positive and currents exiting the IC are negative.
This supply range guarantees that the LOAD voltage is not clamped by the overvoltage limit.
Supply current specified with no load on the LOAD pin.
V
LOFF
voltage specified with a 2.5mA load applied to LOAD.
Not production tested. Guaranteed by design.
I
SCL
is the current limit when the output voltage is initially ramping up.
I
OVL
is the current limit after the output voltage ramping is complete.
Typical Operating Characteristics
(V
CC
= 12V, T
A
= +25°C, R
ILIM
= 56Ω, V
CC
= 12V, C
TIMER
= 0.1µF, C
VRAMP
= 0.1µF, unless otherwise noted.)
CURRENT LIMIT vs. R
ILIM
I
OVL
DS4560 toc01
CURRENT LIMIT vs. TEMPERATURE
DS4560 toc02
OVERVOLTAGE CLAMP vs. TEMPERATURE
DS4560 toc03
10
7
6
I
OVL
CURRENT LIMIT (A)
5
4
3
2
I
SCL
1
16.4
16.2
OVERVOLTAGE CLAMP (V)
16.0
NO LOAD
15.8
15.6
15.4
15.2
15.0
10Ω LOAD
CURRENT LIMIT (A)
1
I
SCL
0.1
10
100
R
ILIM
(Ω)
1000
0
-40 -20
0
20
40
60
80 100 120 140
TEMPERATURE (°C)
-40 -20
0
20
40
60
80 100 120 140
TEMPERATURE (°C)
ON-RESISTANCE vs. TEMPERATURE
DS4560 toc04
SUPPLY CURRENT vs. TEMPERATURE
1.75
1.50
I
CC
(mA)
1.25
1.00
0.75
0.50
0.25
5V/div
0V
DS4560 toc05
TYPICAL DS4560 TURN-ON WAVEFORMS
V
CC
= 18V, 10Ω RESISTIVE LOAD
DS4560 toc06
45
2.00
40
V
CC
LOAD
VRAMP
TIMER
R
ON
(mΩ)
35
30
25
20
-40 -20
0
20
40
60
80 100 120 140
TEMPERATURE (°C)
0
-40 -20
0
20
40
60
80 100 120 140
2ms/div
TEMPERATURE (°C)
_______________________________________________________________________________________
3
12V Hot-Plug Switch
DS4560
Typical Operating Characteristics (continued)
(V
CC
= 12V, T
A
= +25°C, R
ILIM
= 56Ω, V
CC
= 12V, C
TIMER
= 0.1µF, C
VRAMP
= 0.1µF, unless otherwise noted.)
TURN-ON WAVEFORMS
10Ω RESISTIVE LOAD
DS4560 toc07
TURN-ON WAVEFORMS
3300μF CAPACITIVE LOAD
DS4560 toc08
V
CC
2V/div
0V
LOAD
2V/div
V
CC
LOAD
0V
LOAD CURRENT
500mA/div
0mA
LOAD CURRENT
500mA/div
0mA
5ms/div
5ms/div
TURN-ON WAVEFORMS
V
CC
= 18V, 10Ω RESISTIVE LOAD
DS4560 toc09
THERMAL SHUTDOWN WITH AUTORETRY
DS4560S-AR+, V
CC
= 18V, 10Ω RESISTIVE LOAD
DS4560 toc10
V
CC
V
CC
5V/div
LOAD
0V
LOAD
5V/div
0V
LOAD CURRENT
500mA/div
0mA
5ms
LOAD CURRENT
500mA/div
0mA
500ms/div
4
_______________________________________________________________________________________
12V Hot-Plug Switch
Block Diagram/Typical Application Circuit
+12V
V
CC
DS4560
UVLO
+5V
VREG
CHARGE
PUMP
CURRENT
LIMIT
LOAD
ILIM
R
ILIM
LOAD
V
CC
DS4560
80μA
+5V
R
THERMAL
LIMIT
80μA
OVERVOLTAGE
LIMIT
R
2.5V
TIMER
EXTERNAL DISABLE
C
TIMER
VRAMP
C
VRAMP
GND
Detailed Description
The DS4560 begins to operate when V
CC
exceeds the
undervoltage lockout level, V
UVLOR
. At this level, the
enable circuit and TIMER pin become active. Once the
device has been enabled, a gate voltage is applied to
the power MOSFET, allowing current to begin flowing
from V
CC
to LOAD. The speed of the output-voltage
ramp is controlled by the capacitance placed at the
VRAMP pin. The load current is continuously monitored
during the initial voltage ramping (I
SCL
) and during nor-
mal operation (I
OVL
). If the current exceeds the current
limit that is set by the external resistance at ILIM, the
gate voltage of the power MOSFET is decreased,
reducing the output current to the set current limit.
Current is limited by the DS4560 comparing the voltage
difference between the LOAD and ILIM pins to an inter-
nal reference voltage. If the output current exceeds the
limit that is set by the R
ILIM
resistor, the gate voltage of
the power MOSFET is decreased, which reduces the
output current to the load.
When the output power is initially ramping up, the current
limit is I
SCL
. Once the voltage ramping is complete, the
current limit is I
OVL
. The lower I
SCL
current limit protects
the source if there is a dead short on initial power-up.
The DS4560 acts as a fuse and automatically disables
the current flowing to the load when the temperature of
the power MOSFET has exceeded the shutdown junc-
tion temperature, T
SHDN
.
_______________________________________________________________________________________
5
京公网安备 11010802033920号
EEWORLD
