LM5050-2
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LM5050-2 High Side OR-ing FET Controller
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FEATURES
DESCRIPTION
•
The LM5050-2 High Side OR-ing FET Controller
operates in conjunction with an external MOSFET as
an ideal diode rectifier when connected in series with
a power source. This OR-ing controller allows
MOSFETs to replace diode rectifiers in power
distribution networks thus reducing both power loss
and voltage drops.
1
2
•
•
•
•
•
•
•
Wide Operating Input Voltage Range: +6V to
+75V
+100 Volt Transient Capability
Charge Pump Gate Driver for External NChannel MOSFET
MOSFET Diagnostic Test Mode
Fast 50ns Response to Current Reversal
2A Peak Gate Turn-off Current
Minimum VDS Clamp for Faster Turn-off
Package: SOT-6 (Thin SOT23-6)
The LM5050-2 controller provides charge pump gate
drive for an external N-Channel MOSFET and a fast
response comparator to turn off the FET when
current flows in the reverse direction. The LM5050-2
can connect power supplies ranging from +6V to
+75V and can withstand transients up to +100V.
APPLICATIONS
•
The LM5050-2 also provides a FET test diagnostic
mode which allows the system controller to test for
shorted MOSFETs.
Active OR-ing of Redundant (N+1) Power
Supplies
Typical Application Circuits
VIN
VLOGIC
Status
+6V to +75V
VOUT
RPULL-UP
Low= OK, High= Fault
IN
GATE
OUT
nFGD
LM5050-2
Shutdown
Low= FET On, High= FET Off
OFF
GND
GND
GND
Figure 1. Full Application with MOSFET Diagnostic
1
2
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
All trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
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LM5050-2
SNVS679B – NOVEMBER 2010 – REVISED MARCH 2013
PS1
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IN
GATE OUT
LM5050-2
GND
PS2
IN
CLOAD
RLOAD
GATE OUT
LM5050-2
GND
Figure 2. Typical Redundant Supply Configuration
Connection Diagram
GND 2
OFF 3
LM5050MK-2
nFGD 1
6 OUT
5 GATE
4 IN
Figure 3. LM5050MK-2
SOT-6 Package (Top View)
PIN DESCRIPTIONS
Pin #
Name
Function
1
nFGD
Open drain output for the FET Test circuit. Status pin used in
conjunction with the OFF test mode pin. When the OFF pin is in the
logic high state, an active low state on nFGD indicates that the forward
voltage (from source to drain) of the external MOSFET is greater than
350 mV. The nFGD pin requires an external pull-up resistor to a voltage
not higher than 5.5V.
2
GND
Ground return for the controller
3
OFF
FET Test Mode control input. Logic low or open state at the OFF pin
will deactivate the FET Test Mode. A logic high state at the OFF pin will
pull the GATE pin low and turn off the external MOSFET. If the body
diode forward voltage of the MOSFET (from source to drain) is greater
than 350mV when the OFF pin is in the high state, the nFGD pin will
indicate that the MOSFET is not shorted by pulling to the active low
state.
4
IN
5
GATE
6
OUT
Voltage sense connection to the external MOSFET Source pin and
supply input to the internal charge pump.
Connection to the external MOSFET Gate.
Voltage sense connection to the external MOSFET Drain pin and
supply pin for biasing the internal control circuitry.
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
2
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Absolute Maximum Ratings
IN, OUT Pins to Ground
GATE Pin to Ground
(1) (2)
(3)
-0.3V to 100V
(3)
-0.3V to 100V
OFF Pin to Ground
-0.3V to 7V
nFGD Pin to Ground (Off)
-0.3V to 7V
−65°C to 150°C
Storage Temperature Range
ESD
HBM (4)
MM (5)
Peak Reflow Temperature
(1)
(2)
(3)
(4)
(5)
(6)
2 kV
150V
(6)
260°C, 30sec
If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/ Distributors for availability and
specifications.
Absolute Maximum Ratings indicate limits beyond which damage to the device may occur, including in-operability and degradation of
device reliability and/or performance. Functional operation of the device and/or non-degradation at the Absolute Maximum Ratings or
other conditions beyond those indicated in the Recommended Operating Conditions is not implied. Operating Range conditions indicate
the conditions at which the device is functional and the device should not be operated beyond such conditions. For specifications and
conditions, see Electrical Characteristics.
The GATE pin voltage is typically 12V above the IN pin voltage when the LM5050-2 is enabled (i.e. OFF Pin is Open or Low, and VIN >
VOUT). Therefore, the Absolute Maximum Rating for the IN pin voltage applies only when the LM5050-2 is disabled (i.e. OFF Pin is logic
high), or for a momentary surge to that voltage since the Absolute Maximum Rating for the GATE pin is also 100V
The Human Body Model (HBM) is a 100 pF capacitor discharged through a 1.5 kΩ resistor into each pin. Applicable test standard is
JESD-22-A114-C.
The Machine Model (MM) is a 200 pF capacitor discharged through a 0Ω resistor (i.e. directly) into each pin. Applicable test standard is
JESD-A115-A.
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Operating Ratings
(1)
IN, OUT Pins
+6.0V to +75V
OFF Pin Voltage
0.0V to 5.5V
nFGD Voltage (Off)
0.0V to 5.5V
nFGD Sink Current (On)
0 mA to 1 mA
−40°C to +125°C
Junction Temperature Range (TJ)
(1)
Absolute Maximum Ratings indicate limits beyond which damage to the device may occur, including in-operability and degradation of
device reliability and/or performance. Functional operation of the device and/or non-degradation at the Absolute Maximum Ratings or
other conditions beyond those indicated in the Recommended Operating Conditions is not implied. Operating Range conditions indicate
the conditions at which the device is functional and the device should not be operated beyond such conditions. For specifications and
conditions, see Electrical Characteristics.
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Electrical Characteristics
Limits in standard type are for TJ = 25°C only; limits in boldface type apply over the operating junction temperature (TJ)
range of -40°C to +125°C. Minimum and Maximum limits are specified through test, design, or statistical correlation. Typical
values represent the most likely parametric norm at TJ = 25°C, and are provided for reference purposes only. Unless
otherwise stated the following conditions apply: VIN = 12.0V, VOUT = 12.0V, VOFF= 0.0V, CGATE= 47 nF, and TJ = 25°C.
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
V
IN Pin
VIN
IIN
Operating Supply Range
IN Pin current
6.0
-
75.0
VIN = 6.0V
GATE = Open
VOUT = VIN - 100 mV
180
240
300
VIN = 12.0V
GATE = Open
VOUT = VIN - 100 mV
262
350
440
VIN = 75.0V
GATE = Open
VOUT = VIN - 100 mV
275
355
460
VIN = 6.0V
VOUT = VIN - 100 mV
74
95
115
VIN = 12.0V
VOUT = VIN - 100 mV
70
110
160
VIN = 75.0V
VOUT = VIN - 100 mV
35
125
265
VIN = 6.0V to 75V
VGATE = VIN
VOUT = VIN - 175 mV
18.0
32.
45.0
VIN = 6.0V
VOUT = VIN - 175 mV
6.0
6.8
7.4
VIN = 12.0V
VOUT = VIN - 175 mV
8.0
11.5
14.7
VIN = 75.0V
VOUT = VIN - 175 mV
8.0
11
14.5
-
27
100
μA
OUT Pin
IOUT
OUT Pin Current
uA
GATE Pin
IGATE(ON)
VGS
tGATE(REV)
4
VGATE - VIN in Forward Operation
(1)
Gate Capacitance Discharge Time at
Forward to Reverse Transition
See Figure 4
CGATE = 0
(2)
uA
V
CGATE = 10 nF
(2)
-
61
-
CGATE = 47 nF
(2)
-
205
425
(3)
-
450
-
ns
ns
tGATE(OFF)
Gate Capacitance DischargeTime at
OFF pin Low to High Transition
See Figure 5
CGATE = 47 nF
IGATE(OFF)
GATE Pin Sink Current
VGATE = VIN + 3V
VOUT > VIN + 100 mV
t ≤ 10ms
1.9
2.8
-
A
VSD(REV)
Reverse VSD Threshold
VIN < VOUT
VIN - VOUT
-37
-27
-17
mV
ΔVSD(REV)
Reverse VSD Hysteresis
mV
VSD(REG)
(1)
(2)
(3)
GATE Pin Source Current
Regulated Forward VSD Threshold
VIN > VOUT
-
10
-
VIN = 6.0V
VIN - VOUT
6
20
33
VIN = 12.0V
VIN - VOUT
2
16
31
mV
Measurement of VGS voltage (i.e. VGATE - VIN) includes 1 MΩ in parallel with CGATE
Time from VIN-VOUT voltage transition from 200mV to -500mV until GATE pin voltage falls to VIN + 1V. See Figure 4
Time from VOFF voltage transition from 0.0V to 5.0V until GATE pin voltage falls to VIN + 1V. See Figure 5
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Electrical Characteristics (continued)
Limits in standard type are for TJ = 25°C only; limits in boldface type apply over the operating junction temperature (TJ)
range of -40°C to +125°C. Minimum and Maximum limits are specified through test, design, or statistical correlation. Typical
values represent the most likely parametric norm at TJ = 25°C, and are provided for reference purposes only. Unless
otherwise stated the following conditions apply: VIN = 12.0V, VOUT = 12.0V, VOFF= 0.0V, CGATE= 47 nF, and TJ = 25°C.
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
OFF Pin
VOFF(IH)
OFF Input High Threshold Voltage
VOUT = VIN-500 mV
VOFF Rising
-
1.55
1.73
VOFF(IL)
OFF Input Low Threshold Voltage
VOUT = VIN - 500 mV
VOFF Falling
1.09
1.41
-
ΔVOFF
OFF Threshold Voltage Hysteresis
VOFF(IH) - VOFF(IL)
-
160
-
mV
OFF Pin Internal Pull-down
VOFF = 5.0V
2.0
5
8.0
µA
FET Test Threshold Voltage
VIN < VOUT
VOFF = 5V
VOUT = 12V
VIN falling from 12V
250
350
450
mV
IOFF
V
nFGD Pin
VSD(TST)
ΔVSD(TST)
FET Test Threshold Voltage Hysteresis
-
95
-
mV
nFGDVOL
nFGD Output Low Voltage
nFGD Output = On
VOFF = 5V
InFGD = 1 mA Sinking
-
630
850
mV
nFGDIOL
nFGD Output Leakage Current
nFGD Output = Off
VOFF = 0V
VnFGD = 5.5V
-
0.001
0.7
µA
VIN - VOUT
200 mV
VSD(REG)
0 mV
VIN > VOUT
VSD(REV)
VIN < VOUT
-500 mV
VGATE - VIN
tGATE(OFF)
VGATE
1.0V
0.0V
Figure 4. Gate Off Timing for Forward to Reverse Transition
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VOFF
5.0V
VOFF(IH)
VOFF(IL)
0.0V
VGATE - VIN
tGATE(OFF)
VGATE
1.0V
0.0V
Figure 5. Gate Off Timing for OFF pin Low to High Transition
6
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Typical Performance Characteristics
Unless otherwise stated VIN = 12V, VOFF = 0.0V, and TJ = 25°C
IIN
vs
VIN
IOUT
vs
VOUT
Figure 6.
Figure 7.
VGATE
vs
VIN
VGS
vs
VIN
Figure 8.
Figure 9.
VGS
vs
Temperature
Forward Gate Charge Time, CGATE = 10 nF
Figure 10.
Figure 11.
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Typical Performance Characteristics (continued)
Unless otherwise stated VIN = 12V, VOFF = 0.0V, and TJ = 25°C
8
Forward Gate Charge Time, CGATE = 47 nF
Reverse CGATE Discharge
Figure 12.
Figure .
tGATE(REV)
vs
Temperature
OFF Pin Thresholds
vs
Temperature
Figure 13.
Figure 14.
OFF Pin Pull-Down
vs
VOUT
CGATE Charge and Discharge
vs
OFF Pin
Figure 15.
Figure 16.
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Typical Performance Characteristics (continued)
Unless otherwise stated VIN = 12V, VOFF = 0.0V, and TJ = 25°C
OFF Pin, On to Off Transition
OFF Pin, Off to On Transition
Figure 17.
Figure .
GATE Pin
vs
(RDS(ON) x IDS)
Figure 18.
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BLOCK DIAGRAM
INPUT
LOAD
IN
GATE
OUT
17V
30 µA
+12V Charge
Pump
30 mV
+ -
35 µA
30 mV
-
2A
MOSFET Off
Reverse
Comparator
+
Forward
Comparator
350 mV
+
-
Bias
Circuitry
nFGD
OFF
5 µA
+
1.5V
-
GND
LM5050- 2
10
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APPLICATIONS INFORMATION
FUNCTIONAL DESCRIPTION
Systems that require high availability often use multiple, parallel-connected redundant power supplies to improve
reliability. Schottky OR-ing diodes are typically used to connect these redundant power supplies to a common
point at the load. The disadvantage of using OR-ing diodes is the forward voltage drop, which reduces the
available voltage, and the associated power losses as load currents increase. Using an N-channel MOSFET to
replace the OR-ing diode requires a small increase in the level of complexity, but reduces, or eliminates, the
need for diode heat sinks or large thermal copper area in circuit board layouts for high power applications.
PS1
CLOAD
RLOAD
PS2
Figure 19. Traditional OR-ing with Diodes
The LM5050-2 is a positive voltage (i.e. high-side) OR-ing controller that will drive an external N-channel
MOSFET to replace an OR-ing diode. The voltage across the MOSFET source and drain pins is monitored by
the LM5050-2 at the IN and OUT pins, while the GATE pin drives the MOSFET to control its operation based on
the monitored source-drain voltage. The resulting behavior is that of an ideal rectifier with source and drain pins
of the MOSFET acting as the anode and cathode pins of a diode respectively.
PS1
IN
GATE OUT
LM5050-2
GND
PS2
IN
CLOAD
RLOAD
GATE OUT
LM5050-2
GND
Figure 20. OR-ing with MOSFETs
IN, GATE AND OUT PINS
When power is initially applied, the load current will flow from source to drain through the body diode of the
MOSFET. The resulting voltage across the body diode will be detected at the LM5050-2 IN and OUT pins which
then begins charging the MOSFET gate through a 30 µA (typical) charge pump current source . In normal
operation, the gate of the MOSFET is charged until it reaches typically 12V above the IN pin. With an IN pin
voltage that is less than approximately 10V, the gate of the MOSFET is charged to typically twice the voltage on
the IN pin.
The LM5050-2 is designed to regulate the MOSFET gate-to-source voltage if the voltage across the MOSFET
source and drain pins falls below the VSD(REG) voltage of 27 mV (typical).
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If the MOSFET current decreases to the point that the voltage across the MOSFET falls below the VSD(REG)
voltage regulation point of 27 mV (typical), the GATE pin voltage will be decreased until the voltage across the
MOSFET is regulated at 27 mV. If the drain-to-source voltage is greater than VSD(REG) voltage the gate-to-source
will increase, eventually reaching the 12V GATE to IN zener clamp level.
If the MOSFET current reverses, possibly due to failure of the input supply, such that the voltage across the
LM5050-2 IN and OUT pins is more negative than the VSD(REV) voltage of -27 mV (typical), the LM5050-2 will
quickly discharge the MOSFET gate through a strong GATE to IN pin discharge transistor.
If the input supply fails abruptly, as would occur if the supply was shorted directly to ground, a reverse current
will temporarily flow through the MOSFET until the gate can be fully discharged. This reverse current is sourced
from the output load capacitance and from the parallel connected supplies. The LM5050-2 responds to a voltage
reversal condition typically within 27 ns. The actual time required to turn off the MOSFET will depend on the
charge held by gate capacitance of the MOSFET being used. A MOSFET with 47 nF of effective gate
capacitance can be turned off in typically 205 ns. This fast turn off time minimizes voltage disturbances at the
output, as well as the current transients from the redundant supplies.
OFF PIN and nFGD PIN
The OFF pin is a logic level input pin that is used to control the gate drive to the external MOSFET in the FET
Test Mode. The maximum operating voltage on this pin is 5.5V. The nFGD pin is an open drain output pin that
supports a logic level voltage. The maximum operating voltage on this pin is 5.5V.
When the OFF pin is high, the MOSFET is turned off (independent of the sensed IN and OUT voltages) and the
FET Test Mode is activated. In this mode, load current will flow through the body diode of the MOSFET. The
voltage difference between the IN pin and OUT pins will be approximately 700 mV if the MOSFET is operating
normally through the body diode. The FET test comparator of the LM5050-2 monitors the IN to OUT pin voltage
difference with a VSD(TST) threshold of 350 mV (typical). If the IN pin to OUT pin voltage difference is greater than
this threshold, the nFGD pin will switch to a low impedance state and the nFGD pin voltage will be at a logic low.
If the MOSFET is shorted, the voltage difference between the IN pin and the OUT pin will be less than the
VSD(TST) threshold. In this case, the nFGD pin will remain in a high impedance state and the pin voltage can be
pulled high by an external pull-up resistor.
In normal operation the OFF pin must be pulled low (or left open). In this mode, the GATE pin voltage will
depend upon the forward or reverse voltage across the MOSFET source to drain as previously described.
The OFF pin has an internal pull-down of 5 µA (typical). If the OFF function is not required, the pin may be left
open or connected to ground.
While the OFF pin is low the nFGD pin will always be in a high impedance open state.
Several factors can prevent the nFGD pin from indicating that the external MOSFET is operating normally. If the
LM5050-2 is used to connect parallel, redundant power supplies, one of the connected supplies may hold the
OUT pin voltage close enough to the LM5050-2 IN pin voltage that the VSD(TST) threshold is not exceeded.
Additionally, operating with a high output capacitance value and low load current may require a significant
amount of time before the output capacitance is discharged to the point where the VSD(TST) threshold is exceeded
and the nFGD pin switches low.
CLOAD
PS1
IN
RLOAD
GATE OUT
LM5050-2
GND
COUT
PS2
IN
GATE OUT
LM5050-2
GND
Figure 21. Typical Connection
12
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SHORT CIRCUIT FAILURE OF AN INPUT SUPPLY
An abrupt zero ohm short circuit across the input supply will cause the highest possible reverse current to flow
while the internal LM5050-2 control circuitry discharges the gate of the MOSFET. During this time, the reverse
current is limited only by the RDS(ON) of the MOSFET, along with parasitic wiring resistances and inductances.
Worst case instantaneous reverse current would be limited to:
ID(REV) = (VOUT - VIN) / RDS(ON)
(1)
The internal Reverse Comparator will react, and will start the process of discharging the Gate, when the reverse
current reaches:
ID(REV) = VSD(REV) / RDS(ON)
(2)
When the MOSFET is finally switched off, the energy stored in the parasitic wiring inductances will be transferred
to the rest of the circuit. As a result, the LM5050-2 IN pin will see a negative voltage spike while the OUT pin will
see a positive voltage spike. The IN pin can be protected by diode clamping the pin to GND in the negative
direction. The OUT pin can be protected with a TVS protection diode, a local bypass capacitor, or both. In low
voltage applications, the MOSFET drain-to-source breakdown voltage rating may be adequate to protect the
OUT pin (i.e. VIN + V(BR)DSS(MAX) < 75V ), but most MOSFET datasheets do not specifiy the maximum breakdown
rating, so this method should be used with caution.
Parasitic
Inductance
Reverse Recovery Current
IN
Shorted
Input
GATE OUT
LM5050-2
Parasitic
Inductance
COUT
CLOAD
GND
Figure 22. Input Supply Fault Transients
Table 1. FET Test Status Table
OFF
Pin
Mode
FET
Gate
Drive
VIN - VOUT
FET
Status
nFGD
Pin
Status
nFGD
Pin
Voltage
Low or
Open
Normal
Operation
Active
-
-
High Z
High
High
FET Test
Off
> VSD(TST)
OK
Low Z
Low
< VSD(TST)
Not OK
High Z
High
MOSFET SELECTION
The important MOSFET electrical parameters are the maximum continuous Drain current ID, the maximum
Source current (i.e. body diode), the maximum drain-to-source voltage VDS(MAX), the gate-to-source threshold
voltage VGS(TH), the drain-to-source reverse breakdown voltage V(BR)DSS, and the drain-to-source On resistance
RDS(ON).
The maximum continuous drain current, ID, rating must be exceed the maximum continuous load current. The
rating for the maximum current through the body diode, IS, is typically rated the same as, or slightly higher than
the drain current, but body diode current only flows while the MOSFET gate is being charged to VGS(TH):
Gate Charge Time = Qg / IGATE(ON)
(3)
The maximum drain-to-source voltage, VDS(MAX), must be high enough to withstand the highest differential voltage
seen in the application. This would include any anticipated fault conditions.
The drain-to-source reverse breakdown voltage, V(BR)DSS, may provide some transient protection to the OUT pin
in low voltage applications by allowing conduction back to the IN pin during positive transients at the OUT pin.
The gate-to-source threshold voltage, VGS(TH), should be compatible with the LM5050 gate drive capabilities.
Logic level MOSFETs are recommended, but sub-Logic level MOSFETs can also be used.
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The dominate MOSFET loss for the LM5050 active OR-ing controller is conduction loss due to source-to-drain
current to the output load, and the RDS(ON) of the MOSFET. This conduction loss could be reduced by using a
MOSFET with the lowest possible RDS(ON). However, contrary to popular belief, arbitrarily selecting a MOSFET
based solely on having low RDS(ON) may not always give desirable results for several reasons:
1) Reverse transition detection. Higher RDS(ON) will provide increased voltage information to the LM5050 Reverse
Comparator at a lower reverse current level. This will give an earlier MOSFET turn-off condition should the input
voltage become shorted to ground. This will minimize any disturbance of the redundant bus.
2) Reverse current leakage. In cases where multiple input supplies are closely matched it may be possible for
some small current to flow continuously through the MOSFET drain to source (i.e. reverse) without activating the
LM5050 Reverse Comparator. Higher RDS(ON) will reduce this reverse current level.
3) Cost. Generally, as the RDS(ON) rating goes lower, the cost of the MOSFET goes higher.
Selecting a MOSFET with an RDS(ON) that is too large will result in excessive power dissipation. Additionally, the
MOSFET gate will be charged to the full value that the LM5050 can provide as it attempts to drive the Drain to
Source voltage down to the VSD(REG) of 20 mV typical. This increased Gate charge will require some finite
amount of additional discharge time when the MOSFET needs to be turned off.
As a guideline, it is suggest that RDS(ON) be selected to provide at least 20 mV, and no more than 100 mV, at the
nominal load current.
(20 mV / ID) ≤ RDS(ON) ≤ (100mV / ID)
(4)
The thermal resistance of the MOSFET package should also be considered against the anticipated dissipation in
the MOSFET in order to ensure that the junction temperature (TJ) is reasonably well controlled, since the RDS(ON)
of the MOSFET increases as the junction temperature increases.
PDISS = ID2 x (RDS(ON))
(5)
Operating with a maximum ambient temperature (TA(MAX)) of 35°C, a load current of 10A, and an RDS(ON) of 10
mΩ, and desiring to keep the junction temperature under 100°C, the maximum junction-to-ambient thermal
resistance rating (θJA) would need to be:
θJA≤ (TJ(MAX) - TA(MAX))/(ID2 x RDS(ON))
θJA≤ (100°C - 35°C)/(10A x 10A x 0.01Ω)
θJA≤ 65°C/W
14
(6)
(7)
(8)
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Copyright © 2010–2013, Texas Instruments Incorporated
Product Folder Links: LM5050-2
LM5050-2
www.ti.com
SNVS679B – NOVEMBER 2010 – REVISED MARCH 2013
TYPICAL APPLICATIONS
Q1
SUM40N10-30
VIN
6V to 75V
VLOGIC
5.0V
R1
100 k:
CIN
1 PF
100V
VOUT
D1
B180-13-F
IN
STATUS
nFGD
OFF/ON
OFF
OUT
GATE
LM5050-2
GND
GND
GND
Figure 23. Basic Application with Input Transient Protection
Q1
SUM40N10-30
VIN
48V
VLOGIC
5.0V
R1
100 k:
CIN
1 PF
75V
VOUT
48V
D2
SMBJ60A
D1
SS16T3
IN
STATUS
nFGD
OFF/ON
OFF
+
OUT
GATE
LM5050-2
COUT
22 PF
63V
GND
GND
GND
Figure 24. Typical +48V Application with Transient Protection
Q1
SUM40N15-38
VIN
48V
CIN
1 PF
75V
D1
SS16T3
IN
GATE
OUT
LM5050-2
VOUT
48V
D2
SMBJ100A
+ COUT
22 PF
63V
OFF
GND
D3
SS16T3
GND
GND
Figure 25. +48V Application with Reversed Input Voltage (VIN = -48V) Protection
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Copyright © 2010–2013, Texas Instruments Incorporated
Product Folder Links: LM5050-2
15
LM5050-2
SNVS679B – NOVEMBER 2010 – REVISED MARCH 2013
www.ti.com
REVISION HISTORY
Changes from Revision A (March 2013) to Revision B
•
16
Page
Changed layout of National Data Sheet to TI format .......................................................................................................... 15
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Copyright © 2010–2013, Texas Instruments Incorporated
Product Folder Links: LM5050-2
PACKAGE OPTION ADDENDUM
www.ti.com
10-Dec-2020
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
(4/5)
(6)
LM5050MK-2/NOPB
ACTIVE
SOT-23-THIN
DDC
6
1000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
SZJB
LM5050MKX-2/NOPB
ACTIVE
SOT-23-THIN
DDC
6
3000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
SZJB
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of
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