LINER LTC4413EDD2-TR

LTC4413-1/LTC4413-2
Dual 2.6A, 2.5V to 5.5V
Fast Ideal Diodes
in 3mm × 3mm DFN
DESCRIPTION
FEATURES
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2-Channel Ideal Diode OR’ing or Load Sharing
Low Loss Replacement for PowerPathTM OR’ing
Diodes
Fast Response Replacement for LTC4413
Low Forward On Resistance (140mΩ Max at 3.6V)
Low Reverse Leakage Current
Low Regulated Forward Voltage (18mV Typ)
Overvoltage Protection Sensor with Drive Output for
an External P-Channel MOSFET (LTC4413-2 Only)
2.5V to 5.5V Operating Range
2.6A Maximum Forward Current
Internal Current Limit Protection
Internal Thermal Protection
Status Output to Indicate if Selected Channel is
Conducting
Programmable Channel On/Off
Low Profile (0.75mm) 10-Lead 3mm × 3mm DFN
Package
APPLICATIONS
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Battery and Wall Adapter Diode OR’ing in Handheld
Products
Backup Battery Diode OR’ing
Power Switching
USB Peripherals
Uninterruptable Supplies
The LTC®4413-1 and LTC4413-2 each contain two monolithic ideal diodes, each capable of supplying up to 2.6A
from input voltages between 2.5V and 5.5V. The ideal
diodes use a 100mΩ P-channel MOSFET to independently
connect INA to OUTA and INB to OUTB. During normal
forward operation, the voltage drops across each of
these diodes are regulated to as low as 18mV. Quiescent
current is less than 80μA for diode currents up to 1A. If
either of the output voltages exceeds its respective input
voltage, that MOSFET is turned off and less than 1μA of
reverse current flows from OUT to IN. Maximum forward
current in each MOSFET is limited to a constant 2.6A and
internal thermal limiting circuits protect the part during
fault conditions. An internal overvoltage protection sensor
detects when a voltage exceeds the LTC4413-2 absolute
maximum voltage tolerance.
Two active-high control pins independently turn off the two
ideal diodes contained within the LTC4413-1/LTC4413-2.
When the selected channel is reverse biased, or the
LTC4413-1/LTC4413-2 is put into low power standby, the
status signal is pulled low by an 11μA open drain.
The LTC4413-1/LTC4413-2 are housed in a 10-lead 3mm
× 3mm DFN package.
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
PowerPath is a trademark of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
TYPICAL APPLICATION
Power Loss vs Load
Automatic Switchover from a Battery to a Wall Adapter
FDR8508
600
VCC
OUTA
INA
10μF
0.1μF
1Ω
BAT
+
470k
IDEAL
ENBA
STAT
LTC4413-2
GND
OVI
ENBB
INB
STAT
OVP
OVP
OUTB
TO LOAD
4.7μF
IDEAL
441312 TA01a
STAT IS HIGH WHEN WALL ADAPTER IS
SUPPLYING LOAD CURRENT
OVP IS HIGH WHEN WALL ADAPTER VOLTAGE > 6V
POWER LOSS (mW)
WALL
ADAPTER
INPUT
700
500
LTC4413-1
400
300
1N5817
200
100
0
0
500
1000 1500 2000
LOAD (mA)
2500
3000
441312 TA01b
441312fb
1
LTC4413-1/LTC4413-2
ABSOLUTE MAXIMUM RATINGS
(Note 1)
INA, INB, OUTA, OUTB, STAT,
ENBA, ENBB Voltage .................................... –0.3V to 6V
OVI, OVP Voltage ....................................... –0.3V to 13V
Operating Temperature Range.................. –40°C to 85°C
Storage Temperature Range................... –65°C to 125°C
Continuous Power Dissipation ..........................1500mW
(Derate 25mW/°C Above 70°C)
PIN CONFIGURATION
TOP VIEW
TOP VIEW
INA
1
10 OUTA
INA
1
ENBA
2
9 STAT
ENBA
2
GND
3
8 NC
GND
3
ENBB
4
7 NC
ENBB
4
7 OVP
INB
5
6 OUTB
INB
5
6 OUTB
11
DD PACKAGE
10-LEAD (3mm × 3mm) PLASTIC DFN
TJMAX = 125°C, θJA = 43°C/W
EXPOSED PAD (PIN 11) IS GND, MUST BE SOLDERED TO PCB
10 OUTA
9 STAT
11
8 OVI
DD PACKAGE
10-LEAD (3mm × 3mm) PLASTIC DFN
TJMAX = 125°C, θJA = 43°C/W
EXPOSED PAD (PIN 11) IS GND, MUST BE SOLDERED TO PCB
ORDER INFORMATION
LEAD FREE FINISH
TAPE AND REEL
PART MARKING
PACKAGE DESCRIPTION
TEMPERATURE RANGE
LTC4413EDD1#PBF
LTC4413EDD1#TRPBF
LCPP
10-Lead (3mm × 3mm) Plastic DFN
–40°C to 85°C
LTC4413EDD2#PBF
LTC4413EDD2#TRPBF
LCPQ
10-Lead (3mm × 3mm) Plastic DFN
–40°C to 85°C
LEAD BASED FINISH
TAPE AND REEL
PART MARKING
PACKAGE DESCRIPTION
TEMPERATURE RANGE
LTC4413EDD1
LTC4413EDD1#TR
LCPP
10-Lead (3mm × 3mm) Plastic DFN
–40°C to 85°C
LTC4413EDD2
LTC4413EDD2#TR
LCPQ
10-Lead (3mm × 3mm) Plastic DFN
–40°C to 85°C
Consult LTC Marketing for parts specified with wider operating temperature ranges.
For more information on lead free part marking, go to: http://www.linear.com/leadfree/
For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/
ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. (Notes 2, 6)
SYMBOL
PARAMETER
CONDITIONS
MIN
VIN, VOUT
Operating Supply Range for Channel A or B VIN and/or VOUT Must be in This Range for
Proper Operation
●
UVLO
UVLO Turn-On Rising Threshold
Max (VINA, VINB, VOUTA, VOUTB)
●
UVLO Turn-Off Falling Threshold
Max (VINA, VINB, VOUTA, VOUTB)
●
IQF
Quiescent Current in Forward Regulation,
Measured via GND
VINA = 3.6V, IINA = 100mA, VINB = 0V,
IINB = 0mA (Note 3)
●
IQRIN
Current Drawn from or Sourced into IN
when VOUT is greater than VIN
VIN = 3.6V, VOUT = 5.5V (Note 6)
●
IQRGND
Quiescent Current While in Reverse
Turn-Off, Measured via GND
VINA = VINB = 0V, VOUTB = VOUTA = 5.5V,
VSTAT = 0V
TYP
2.5
MAX
5.5
V
2.45
V
40
58
μA
2.5
4.5
μA
28
36
μA
1.7
–1
UNITS
V
441312fb
2
LTC4413-1/LTC4413-2
ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. (Notes 2, 6)
SYMBOL
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
3.5
6.5
μA
28
38
μA
10
mV
18
24
mV
IQROUTB
Quiescent Current While in Reverse
Turn-Off. Current Drawn from VOUTA when
OUTB Supplies Chip Power
VINA = VINB = 0V, VOUTA = 3.6V, VOUTB = 5.5V
●
IQOFF
Quiescent Current with Both ENBA and
ENBB High
VINA = VINB = 3.6V, VENBA = VENBB = 1V
●
VRTO
Reverse Turn-Off Voltage (VOUT – VIN)
VIN = 3.6V
●
VFWD
Forward Voltage Drop (VIN – VOUT)
at IOUT = –1mA
VIN = 3.6V
●
RFWD
On-Resistance, RFWD Regulation
(Measured as ΔV/ΔI)
VIN = 3.6V, IOUT = –100mA to –500mA (Note 5)
100
140
mΩ
RON
On-Resistance, RON Regulation
(Measured as V/I at IIN = 1A)
VIN = 3.6V, IIN = 1A (Note 5)
140
200
mΩ
tON
PowerPath Turn-On Time
VIN = 3.6V, from ENB Falling to IOUT Ramp
Starting
11
μs
tOFF
PowerPath Turn-Off Time
VIN = 3.6V, from ENB Rising with IIN = 100mA
Falling to 0mA
2
μs
–5
Short-Circuit Response
IOC
Current Limit
VINA OR B = 3.6V (Note 5)
1.8
A
IQOC
Quiescent Current While in Overcurrent
Operation
VINA OR B = 3.6V, IOUT = 1.8A (Note 5)
ISOFF
STAT Off Current
Shut Down
●
ISON
STAT Sink Current
VIN > VOUT, VCTL < VIL, TJ < 135°C, IOUT < IMAX
●
tS(ON)
STAT Pin Current Turn-On Time
VIN = 3.6V, from ENB Falling
1.8
μs
tS(OFF)
STAT Pin Current Turn-Off Time
VIN = 3.6V, from ENB Rising
0.8
μs
VENBIH
ENB Inputs Rising Threshold Voltage
VENB Rising
●
VENBIL
ENB Inputs Falling Threshold Voltage
VENB Falling
●
VENBHYST
ENB Input Hysteresis
VENBHYST = (VENBIH – VENBIL)
100
130
μA
–1
0
1
μA
7
11
13
μA
STAT Output
ENB Inputs
IENB
ENB Inputs Pull-Down Current
VOUT < VIN = 3.6V, VENB < VIL
●
540
400
2
600
mV
460
mV
90
mV
3
4
μA
5.9
6.2
V
OVI Input (LTC4413-2 Only)
VOVIH
OVI Input Rising Threshold Voltage
VOVI Rising
VOVIL
OVI Input Falling Threshold Voltage
VOVI Falling
VOVID
OVI-OVP Voltage Drop
IOVI
OVI Bias Current
5.6
V
VOVI = 8V, No Load at OVP
100
mV
VOVI = 8V
80
μA
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: The LTC4413-1/LTC4413-2 are guaranteed to meet performance
specifications from 0°C to 85°C. Specifications over the –40°C to
85°C ambient operating temperature range are assured by design,
characterization and correlation with statistical process controls.
Note 3: Quiescent current increases with diode current: refer to plot of
IQF vs IOUT.
5.4
Note 4: This IC includes overtemperature protection that is intended
to protect the device during momentary overload conditions.
Overtemperature protection will become active at a junction temperature
greater than the maximum operating temperature. Continuous operation
above the specified maximum operating junction temperature may impair
device reliability.
Note 5: Specification is guaranteed by correlation to wafer-level
measurements.
Note 6: Unless otherwise specified, current into a pin is positive and
current out of a pin is negative. All voltages referenced to GND.
441312fb
3
LTC4413-1/LTC4413-2
TYPICAL PERFORMANCE CHARACTERISTICS
IQF vs ILOAD (Log)
IQF vs ILOAD (Linear)
120
IQF vs Temperature
120
120
120°C
120°C
100
80°C
40°C
40°C
0°C
–40°C
60
80
–40°C
60
500mA
60
40
40
40
20
20
20
0
1
10
100
LOAD (mA)
1000
0
10000
0
2500
1000 1500 2000
LOAD (mA)
500
441312 G01
IQF vs VIN
2.20
3000
2.15
2500
IOC (mA)
2000
IQF = 100mA
40
40
80
TEMPERATURE (°C)
30
120
UVLO Thresholds vs Temperature
3500
60
50
0
441312 G03
UVLO THRESHOLDS (V)
IQF = 1A
70
1mA
0
–40
3000
IOC vs Temperature
80
100mA
441312 G02
90
IQF (μA)
1A
0°C
80
IQF (μA)
IQF (μA)
80
100
IQF (μA)
80°C
100
1500
1000
RISING
2.10
2.05
2.00
FALLING
1.95
20
500
10
2
2.5
3
3.5
4
4.5
5
5.5
0
–40
6
0
VIN (V)
40
UVLO Hystersis vs Temperature
ENB Hysteresis vs Temperature
120
100
500
ENBIH/ENBIL (mV)
100
50
ENBIH
ENBIL
400
300
200
100 120
441312 G07
0
–40
80
60
40
20
100
20 40
60 80
TEMPERATURE (°C)
120
80
441312 G06
ENB Thresholds vs Temperature
200
150
40
TEMPERATURE (°C)
600
0
0
441312 G05
250
UVLO HYSTERESIS (mV)
1.85
–40
TEMPERATURE (°C)
441312 G04
0
–40 –20
120
80
ENB HYSETERSIS (mV)
0
1.90
0
40
80
TEMPERATURE (°C)
120
441312 G08
0
–40 –20
0
20 40 60 80
TEMPERATURE (°C)
100 120
441312 G09
441312fb
4
LTC4413-1/LTC4413-2
TYPICAL PERFORMANCE CHARACTERISTICS
VFWD and RFWD vs ILOAD (Linear)
500
120°C
80°C
40°C
0°C
–40°C
78
400
76
RFWD (mΩ)
68
500
200
VFWD
400
300
150
200
100
66
RFWD
64
100
50
300
120°C
80°C
40°C
0°C
–40°C
RFWD
250
200
VFWD
300
150
200
100
100
50
VFWD (mV)
70
600
VFWD (mV)
RFWD 500mA (mΩ)
74
72
RFWD and VFWD vs ILOAD (Log)
250
RFWD (mΩ)
RFWD vs VIN and ILOAD = 500mA
80
62
0
60
2.5
3.5
3
4
4.5
VIN (V)
5
5.5
6
0
500
1000 1500 2000
LOAD (mA)
2500
VFWD vs ILOAD (Log)
100
LOAD (mA)
0
10000
1000
441312 G12
ILEAK vs Temperature at
VREVERSE = 5.5V
1
120
100
0.1
100mA
80
RFWD (mΩ)
VFWD (mV)
10
RFWD vs Temperature
120°C
80°C
40°C
0°C
–40°C
200
1
441312 G11
441312 G10
250
0
0
3000
150
100
500mA
ILEAK (μA)
2
1A
60
5.5V
0.01
3.6V
0.001
40
50
0.0001
20
0
10
1
100
LOAD (mA)
1000
10000
0
–40
0
40
80
TEMPERATURE (°C)
441312 G13
120
0
20 40 60 80
TEMPERATURE (°C)
100 120
441312 G15
441312 G14
Response to 800mA Load Step
in <16μs
ILEAK vs VREVERSE
0.00001
–40 –20
ENB Turn-On, 30μs to Turn On
with 180mA Load
100
120°C
80°C
40°C
0°C
–40°C
10
ILEAK (μA)
1
CH1 = IN 100mV/DIV
CH1 IN 1V/DIV
CH2 OUT
100mV/DIV
CH3 ENB
1V/DIV
CH2 OUT
1V/DIV
0.1
CH4 IOUT
200mV/DIV
0.01
CH4 IOUT
200mV/DIV
0.001
4μs/DIV
0.0001
441312 G17
10μs/DIV
441312 G18
0.00001
0
1
2
3
4
VREVERSE (V)
5
6
441312 G16
441312fb
5
LTC4413-1/LTC4413-2
TYPICAL PERFORMANCE CHARACTERISTICS
ENB Turn-Off, 2μs to Disconnect
IN from 180mA Load
Efficiency vs Load Current
Power Loss vs Load Current
100
1000
120°C
80°C
40°C
0°C
–40°C
99
CH1 IN 1V/DIV
CH2 OUT
1V/DIV
CH3 ENB
1V/DIV
CH4 IIN
100mV/DIV
100
97
96
95
94
93
120°C
80°C
40°C
0°C
–40°C
92
441312 G19
4μs/DIV
POWER LOSS (mW)
EFFICIENCY (%)
98
91
90
1
10
10
1
0
100
LOAD (mA)
1000
10000
10
1
100
LOAD (mA)
1000
441312 G20
OVI Current vs Voltage
(LTC4413-2 Only)
6.4
400
140
6.2
350
120
5.8
OVP FALLING
5.6
5.4
5.2
300
200
0
40
20
0
0
TEMPERATURE (°C)
40
80
0
120
160
5
140
IQ OVI = 13V
VOHOVP = 13V
OVI-OVP (mV)
IQ OVI (μA)
OVP (V)
120
120
4
100
IQ OVI = 6.5V
80
60
4
8
6
OVI (V)
10
12
60
20
20
0
–40
0
40
80
120
441312 G26
VOHOVP = 6.5V
80
40
TEMPERATURE (°C)
441312 G25
100
40
1
0
12
160
140
2
10
OVI-OVP vs Temperature
(LTC4413-2 Only)
180
3
8
6
VOVI (V)
441312 G24
IQ OVI vs Temperature
(LTC4413-2 Only)
TA = 25°C
2
4
441312 G23
OVI-OVP Voltage Drop vs OVI
Voltage (LTC4413-2 Only)
0
2
TEMPERATURE (°C)
441312 G22
6
60
40
100
0
–40
120
80
80
150
50
5.0
–40
TA = 25°C
100
250
IOVI (μA)
OVP RISING
6.0
OVP HYSTERESIS (mV)
OVPIH/OVPIL (V)
441312 G21
Overvoltage Hysteresis vs
Temperature (LTC4413-2 Only)
Overvoltage Thresholds vs
Temperature (LTC4413-2 Only)
10000
0
–40 –20
0
20 40 60 80
TEMPERATURE (°C)
100 120
441312 G27
441312fb
6
LTC4413-1/LTC4413-2
PIN FUNCTIONS
INA (Pin 1): Primary Ideal Diode Anode and Positive Power
Supply for LTC4413-1/LTC4413-2. Bypass INA with a ceramic capacitor of at least 1μF. (Series 1Ω snub resistors
and higher valued capacitances are recommended when
large inductances are in series with this input.) This pin
can be grounded when not used. Limit slew rate on this
pin to less than 2.5V/μs.
ENBA (Pin 2): Enable Low for Diode A. Pull this pin high
to shut down this power path. Tie to GND to enable.
Refer to Table 1 for mode control functionality. This pin
can be left floating, a weak (3.5μA) pull-down internal to
LTC4413-1/LTC4413-2 is included.
OVP (Pin 7, LTC4413-2 Only): Drive Output for an External OVP Switch PMOS Transistor (To Inhibit Overvoltage
Wall Adapter Voltages from Damaging Device.) During
overvoltage conditions, this output will remain high so
long as an overvoltage condition persists. This pin must
be left floating when not in use.
OVI (Pin 8, LTC4413-2 Only): Sense Input for Overvoltage
Protection Block. This pin can be left floating or grounded
when not used.
GND (Pin 3): Power Ground for the IC.
STAT (Pin 9): Status Condition Indicator. Weak (11μA)
pull-down current output. When terminated, high indicates
diode conducting. Refer to Table 2 for the operation of this
pin. This pin can also be left floating or grounded.
ENBB (Pin 4): Enable Low for Diode B. Pull this pin high
to shut down this power path. Tie to GND to enable.
Refer to Table 1 for mode control functionality. This pin
can be left floating, a weak (3.5μA) pull-down internal to
LTC4413-1/LTC4413-2 is included.
OUTA (Pin 10): Primary Ideal Diode Cathode and Output
of the LTC4413-1/LTC4413-2. Bypass OUTA with a high
(1mΩ min) ESR ceramic capacitor of at least 4.7μF. This
pin must be left floating when not in use. Limit slew rate
on this pin to less than 2.5V/μs.
INB (Pin 5): Secondary Ideal Diode Anode and Positive
Power Supply for LTC4413-1/LTC4413-2. Bypass INB with a
ceramic capacitor of at least 1μF. (Series 1Ω snub resistors
and higher valued capacitances are recommended when
large inductances are in series with this input.) This pin
can be grounded when not used. Limit slew rate on this
pin to less than 2.5V/μs.
Exposed Pad (Pin 11): Signal Ground. This pin must be
soldered to PCB ground to provide both electrical contact
to ground and good thermal contact to PCB.
OUTB (Pin 6): Secondary Ideal Diode Cathode and Output
of the LTC4413-1/LTC4413-2. Bypass OUTB with a high
(1mΩ min) ESR ceramic capacitor of at least 4.7μF. This
pin must be left floating when not in use. Limit slew rate
on this pin to less than 2.5V/μs.
441312fb
7
LTC4413-1/LTC4413-2
BLOCK DIAGRAM
OUTA
INA
OVER CURRENT
0.5V
2
ENBA
–
+
+
–
1
–+
VOFF
PA
–
+
VGATEA
AENA
ENA
A
UVLO
ENA
ENB
OUTA (MAX)
OUTB (MAX)
AENA
OVER TEMP
BENA
OVER TEMP
STAT
STB
GND
OUTB
INB
OVER CURRENT
0.5V
4
11μA
ENBB
–
+
+
–
5
9
+ –
3μA
3
10
–+
VOFF
ENB
6
PB
LTC4413-2 ONLY
OVERVOLTAGE PROTECTION OVI
–
+
VGATEB
BENA
B
+ –
6V
+
–
OVP
8
7
3μA
441312 BD
441312fb
8
LTC4413-1/LTC4413-2
OPERATION
The LTC4413-1/LTC4413-2 are described with the aid of the
Block Diagram. Operation begins when the power source at
VINA or VINB rises above the undervoltage lockout (UVLO)
voltage of 2.4V and the corresponding control pin ENBA or
ENBB is low. If only the voltage at the VINA pin is present,
the internal power source (VDD) is supplied from the VINA
pin. The amplifier (A) pulls a current proportional to the
difference between VINA and VOUTA from the gate (VGATEA)
of the internal PFET (PA), driving this gate voltage below
VINA. This turns on PA. As VOUTA pulls up to a forward
voltage drop (VFWD) of 15mV below VINA, the LTC4413
regulates VGATEA to maintain the small forward voltage
drop. The system is now in forward regulation and the
load at VOUTA is powered from the supply at VINA. As the
load current varies, VGATEA is controlled to maintain VFWD
until the load current exceeds the transistor’s (PA) ability
to deliver the current as VGATEA approaches GND. At this
point, the PFET behaves as a fixed resistor, RON, whereby
the forward voltage increases slightly with increased load
current. As the magnitude of IOUT increases further, (such
that ILOAD > IOC) the LTC4413-1/LTC4413-2 fixes the load
current to the constant value IOC to protect the device.
The characteristics for parameters RFWD, RON, VFWD and
IOC are specified with the aid of Figure 1, illustrating the
LTC4413-1/LTC4413-2 forward voltage drop versus that
of a Schottky.
If another supply is provided at VINB, the LTC4413-1/
LTC4413-2 likewise regulate the gate voltage on PB to
IOC
maintain the output voltage, VOUTB, just below the input
voltage VINB. If this alternate supply, VINB, exceeds the
voltage at VINA, the LTC4413-1/LTC4413-2 selects this
input voltage as the internal supply (VDD). This second
ideal diode operates independently of the first ideal diode
function.
When an alternate power source is connected to the load
at VOUTA (or VOUTB), the LTC4413-1/LTC4413-2 sense the
increased voltage at VOUTA, and amplifier A increases the
voltage VGATEA, reducing the current through PA. When
VOUTA is higher than VINA + VRTO, VGATEA will be pulled up
to VDD, turning off PA. The internal power source for the
LTC4413-1/LTC4413-2 (VDD) then diverts to draw current
from the VOUTA pin, only if VOUTA is larger than VINB (or
VOUTB). The system is now in the reverse turn-off mode.
Power to the load is being delivered from an alternate
supply, and only a small current (ILEAK) is drawn from or
sourced to VINA to sense the potential at VINA.
When the selected channel of the LTC4413-1/LTC4413-2
is in reverse turn-off mode or both channels are disabled,
the STAT pin sinks 11μA of current (ISON) if connected.
Channel selection is accomplished using the two ENB
pins, ENBA and ENBB. When the ENBA input is asserted
(high), PA has its gate voltage pulled to VDD, turning off
PA. A 3.5μA pull-down current on the ENB pins ensures
a low level at these inputs if left floating.
LTC4413-1
LTC4413-2
CURRENT (A)
SLOPE: 1/RON
IFWD
1N5817
SLOPE: 1/RFWD
0
0 VFWD
FORWARD VOLTAGE (V)
441312 TA01b
Figure 1. The LTC4413 vs the 1N5817
441312fb
9
LTC4413-1/LTC4413-2
OPERATION
Overcurrent and Short-Circuit Protection
During an overcurrent condition, the output voltage droops
as the load current exceeds the amount of current that
the LTC4413-1/LTC4413-2 can supply. At the time when
an overcurrent condition is first detected, the LTC4413-1/
LTC4413-2 take some time to detect this condition before
reducing the current to IOC. For short durations after the
output is shorted, until TOC, the current may exceed IOC.
The magnitude of this peak short-circuit current can be
large depending on the load current immediately before
the short circuit occurs. During overcurrent operation, the
power consumption of the LTC4413-1/LTC4413-2 is large,
and is likely to cause an overtemperature condition as the
internal die temperature exceeds the thermal shutdown
temperature.
Overtemperature Protection
The overtemperature condition is detected when the
internal die temperature increases beyond 150°C. An
overtemperature condition will cause the gate amplifiers
(A and B) as well as the two P-channel MOSFETs (PA
and PB) to shut off. When the internal die temperature
cools to below 140°C, the amplifiers turn on and the
LTC4413-1/LTC4413-2 reverts to normal operation. Note
that prolonged operation under overtemperature conditions degrades reliability.
Overvoltage Protection for more information on using the
overvoltage protection function within the LTC4413-2.
Channel Selection and Status Output
Two active-high control pins independently turn off the two
ideal diodes contained within the LTC4413-1/LTC4413-2,
controlling the operation mode as described by Table 1.
When the selected channel is reverse biased, or the
LTC4413-1/LTC4413-2 is put into low power standby, the
status signal indicates this condition with a low voltage.
Table 1: Mode Control
ENB1
ENB2
STATE
Low
Low
Diode’OR NB: The Two Outputs are not Connected
Internal to the Device
Low
High
Diode A = ENABLED, Diode B = DISABLED
High
Low
Diode A = DISABLED, Diode B = ENABLED
High
High
All Off (Low Power Standby)
The function of the STAT pin depends on the mode that
has been selected. Table 2 describes the STAT pin output
current, as a function of the mode selected as well as the
conduction state of the two diodes.
Table 2: STAT Output Pin Function
ENB1
ENB2
CONDITIONS
STAT
Low
Low
Diode A Forward Bias,
Diode B Forward Bias
ISNK = 0μA
Diode A Forward Bias,
Diode B Reverse Bias
ISNK = 0μA
Diode A Reverse Bias,
Diode B Forward Bias
ISNK = 11μA
Diode A Reverse Bias,
Diode B Reverse Bias
ISNK = 11μA
Diode A Forward Bias,
Diode B Disabled
ISNK = 0μA
Diode A Reverse Bias,
Diode B Disabled
ISNK = 11μA
Diode A Disabled,
Diode B Forward Bias
ISNK = 0μA
Diode A Disabled,
Diode B Reverse Bias
ISNK = 11μA
Diode A Disabled,
Diode B Disabled
ISNK = 11μA
Overvoltage Protection (LTC4413-2 Only)
An overvoltage condition is detected whenever the
overvoltage input (OVI) pin is pulled above 6V. The condition persists until the OVI voltage falls below 5.6V. The
overvoltage protection (OVP) output is low unless an
overvoltage condition is detected. If an overvoltage condition is present, the OVP output is pulled up to the voltage
applied to the OVI input. This output signal can be used to
enable or disable an external PFET that is placed between
the input that is the source of the excessive voltage and
the input to the LTC4413-2, thus eliminating the potential
damage that may occur to the LTC4413-2 if its input voltage exceeds the absolute maximum voltage of 6V. See
the Applications Information section Dual Battery Load
Sharing with Automatic Switchover to a Wall Adapter with
Low
High
High
High
Low
High
441312fb
10
LTC4413-1/LTC4413-2
APPLICATIONS INFORMATION
Introduction
The LTC4413-1/LTC4413-2 are intended for power control
applications that include low loss diode OR’ing, fully automatic switchover from a primary to an auxiliary source of
power, microcontroller controlled switchover from a primary to an auxiliary source of power, load sharing between
two or more batteries, charging of multiple batteries from
a single charger and high side power switching.
Dual Battery Load Sharing With Automatic Switchover
to a Wall Adapter With Overvoltage Protection
(LTC4413-2 Only)
An application circuit for dual battery load sharing with
automatic switchover of load from batteries to a wall
adapter is shown in Figure 2. When the wall adapter is not
present, whichever battery has the higher voltage provides
the load current until it has discharged to the voltage of the
other battery. The load is shared between the two batteries according to the capacity of each battery. The higher
capacity battery provides proportionally higher current to
the load. When a wall adapter input is applied, the output
voltage rises as the body diode in MP2 conducts. When
the output voltage is larger than the battery voltages, the
LTC4413 turns off and very little load current is drawn
from the batteries. At this time, the STAT pin pulls down
MP1
MP2
IRLML6402 IRLML6402
WALL
ADAPTER
INPUT
JACK
BATA
+
C1
0.10μF
R1
1Ω
Capacitor C2 is required to dynamically pull up on the
gate of PFET MP1 if a fast edge occurs at the wall adapter
input during a hot plug. In the event that capacitor C2 (or
the gate-to-source of MP1) is precharged below the OVI
rising threshold. When a high voltage spike occurs, the
OVP output cannot guarantee turning off MP1 before the
load voltage exceeds the absolute maximum voltage for
the LTC4413-2. This may occur in the event that the wall
adapter suddenly steps from 5.5V to a much higher value.
In this case, a zener diode is recommended to keep the
output voltage to a safe level.
Automatic PowerPath Control
Figure 3 illustrates an application circuit for microcontroller monitoring and control of two power sources. The
microcontroller’s analog inputs (perhaps with the aid of
a resistor voltage divider) monitor each supply input and
the LTC4413-1 status, and then commands the LTC4413-1
through the two ENBA/ENBB control inputs.
RSTAT
470k
C2
10nF
MICROCONTROLLER
OPTIONAL
6.2V
DFLZ6V2-7
OUTA 10
1 INA
the gate voltage of MP2, causing it to conduct. This status
signal can be used to provide information as to whether
the wall adapter (or BATB) is supplying the load current.
If the wall adapter voltage exceeds the OVI trip threshold
(VOVIH) then the wall adapter is disconnected via the
external PFET, MP1. The OVI voltage can be monitored
(through a voltage divider if necessary) to determine if
an overvoltage condition is present.
TO LOAD
IDEAL
9
STAT
ENBA
LTC4413-2
3
8
GND
OVI
4
7
ENBB
OVP
OUTB 6
5 INB
PRIMARY
POWER
SOURCE
2
BATB
+
10nF
441312 F02
COUT
4.7μF
IDEAL
Figure 2
RSTAT
470k
1 INA
CA
10μF
RA
1Ω
STAT
OVP
C1: C1206C106K8PAC
C2: C0403C103K8PAC
COUT: C1206C475K8PAC
2
3
OUTA 10
IDEAL
STAT
ENBA
LTC4413-1
GND
9
LOAD
STAT
4
AUXILIARY
POWER
SOURCE
ENBB
5 INB
CB
10μF
OUTB 6
C1
4.7μF
IDEAL
441312 F03
RB
1Ω
Figure 3
441312fb
11
LTC4413-1/LTC4413-2
APPLICATIONS INFORMATION
Automatic Switchover from a Battery to an Auxiliary
Supply, or a Wall Adapter with Overvoltage Protection
Figure 4 illustrates an application circuit where the LTC44132 is used to automatically switch over between a battery,
an auxiliary power supply and a wall adapter. When the
battery is supplying load current, OVP is at GND and STAT
is high. If a higher supply is applied to AUX, the BAT will
be disconnected from the load and the load is powered
from AUX. When a wall adapter is applied, the body diode
of MP2 forward biases. When the load voltage exceeds the
AUX (or BAT) voltage, the LTC4413-2 senses this higher
voltage and disconnects AUX (or BAT) from the load. At
the same time it pulls the STAT voltage to GND, thereby
turning on MP2. The load current is now supplied from the
wall adapter. If the wall adapter voltage exceeds the OVI
rising threshold, the OVP voltage rises and turns off MP1,
disconnecting the wall adapter from the load. The output
voltage collapses down to the AUX (or BAT) voltage and
MP1
MP2
IRLML6402 IRLML6402
WALL
ADAPTER
INPUT
JACK
C1
0.10μF
R1
1Ω
OUTA 10
1 INA
+
3
BAT
4
GND
IDEAL
470k
470k
2
TO LOAD
8
OVP
10nF
OUTB 6
IDEAL
COUT
4.7μF
ENBA
441312 F04
Figure 4
Capacitor C2 is required to dynamically pull up on the
gate of MP1 if a fast edge occurs at the wall adapter input
during a hot plug. If the wall adapter voltage is precharged
when an overvoltage spike occurs, the OVP voltage may
not discharge capacitor C2 in time to protect the output.
In this event, a zener diode is recommended to protect
the output node until MP1 is turned off.
Multiple Battery Charging
Figure 5 illustrates an application circuit for automatic dual
battery charging from a single charger. Whichever battery
has the lower voltage will receive the larger charging current until both battery voltages are equal, then both are
charged. While both batteries are charging simultaneously,
the higher capacity battery gets proportionally higher current from the charger. For Li-Ion batteries, both batteries
achieve the float voltage minus the forward regulation
voltage of 15mV. This concept can apply to more than
two batteries. The STAT pin provides information as to
when the battery at OUTA is being charged. For intelligent
control, the ENBA/ENBB input pins can be used with a
microcontroller as shown in Figure 3.
Automatic Switchover from a Battery to a Wall
OPTIONAL
6.2V
DFLZ6V2-7
OVI
LTC4413-2
7
ENBB
OVP
9
STAT
5 INB
AUX
C2
10nF
the LTC4413-2 reconnects the load to AUX (or BAT).
RSTAT
560k
STAT
C1: C1206C106K8PAC
C2: C0403C103K8PAC
COUT: C1206C475K8PAC
BATTERY
CHARGER
INPUT
OUTA 10
1 INA
2
LOAD
BAT1
ENBA
LTC4413-1
3
9
STAT
GND
4
ENBB
OUTB 6
5 INB
IDEAL
+
VCC
IDEAL
470k STAT IS HIGH
WHEN BAT1 IS
CHARGING
LOAD
+
BAT2
441312 F05
Figure 5
441312fb
12
LTC4413-1/LTC4413-2
APPLICATIONS INFORMATION
Adapter and Charger with Overvoltage Protection
Figure 6 illustrates the LTC4413-2 performing the function
of automatically switching a load over from a battery to a
wall adapter while controlling an LTC4059 battery charger.
When no wall adapter is present, the LTC4413-2 connects
the load at OUTA from the Li-Ion battery at INA. In this
condition, the STAT voltage is high, thereby disabling
the battery charger. If a wall adapter of a higher voltage
than the battery is connected to MP1 (but below the OVI
threshold), the load voltage rises as the second ideal diode conducts. As soon as the OUTA voltage exceeds the
INA voltage, the BAT is disconnected from the load and
the STAT voltage falls, turning on the LTC4059 battery
charger and beginning a charge cycle. If a high voltage
wall adapter is inadvertently attached above the OVI rising
threshold, the OVP pin voltage rises, disconnecting both
the LTC4413-2 and the LTC4059 from potentially hazardous voltages. When this occurs, the load voltage collapses
until it is below the BAT voltage causing the STAT voltage
to rise, disabling the battery charger. At the same time,
the LTC4413-2 automatically reconnects the battery to the
load. One major benefit of this circuit is that when a wall
adapter is present, the user may remove the battery and
replace it without disrupting the load.
Capacitor C2 is required to dynamically pull up on the
gate of MP1 if a fast edge occurs at the wall adapter input
during a hot plug. If the wall adapter voltage is precharged
when an overvoltage spike occurs, the OVP voltage may
not discharge capacitor C2 in time to protect the output.
In this event, a zener diode is recommended to protect
the output node until MP1 is turned off.
Soft-Start Overvoltage Protection
STAT
STAT
ENB
1 INA
BAT
LTC4059
+
VCC PROG
MP1
IRLML6402
Li-Ion
100k
Li/CC GND
WALL
ADAPTER
INPUT
JACK
1μF
C1
10μF
9
OUTA 10
RSTAT
560k
TO
LOAD
IDEAL
ENBA
LTC4413-2
4
ENBB
3
GND
OUTB 6
5 INB
2
D1
OPTIONAL
DFLZ6V2-7
COUT
4.7μF
IDEAL
OVP
C2
10nF
OVI
441312 F06
Figure 6
441312fb
13
LTC4413-1/LTC4413-2
APPLICATIONS INFORMATION
In the event that a low power external PFET is used for
the external overvoltage protection device, care must be
taken to limit the power dissipation in the external PFET.
The operation of this circuit is identical to the “Automatic
Switchover from a Battery to a Wall Adapter” application
shown on the first page of this data sheet. Here, however,
the ideal diode from INA to INB is disabled by pulling up
on ENBA whenever an overvoltage condition is detected.
This channel is turned-off using a resistor connected to
OVP along with a 5.6V zener diode, ensuring the absolute
maximum voltage at ENBA is not exceeded during an
overvoltage event. When the overvoltage condition ends,
the OVP voltage drops slowly, depending on the gate
charge of the external PFET. This causes the external PFET
to linger in a high RDS(ON) region where it can dissipate
a significant amount of heat depending on the load current. To avoid dissipating heat in the external PFET, this
application delays turning on the ideal diode from INA to
OUTA, until the gate voltage of the external PFET drops
below VENBIL, where the external PFET should safely be
out of the high RDS(ON) region. This soft-start scheme can
be used on either channel of the LTC4413-2.
FDR8508
WALL
ADAPTER
INPUT
INA
C1
10μF
C2
10nF
0.1μF
D1
OPTIONAL
OUTA
IDEAL
VCC
RSTAT
470k
RENBA
560k
D2
5.6V
1Ω
BAT
STAT
ENBA
LTC4413-2
OVI
GND
STAT
OVP
OUTB
OVP
ENBB
INB
+
COUT
4.7μF
IDEAL
TO LOAD
441312 F07
C1: C0805C106K8PAC
C2: C0403C103K8PAC
COUT: C1206C475K8PAC
STAT IS HIGH WHEN WALL ADAPTER IS
SUPPLYING LOAD CURRENT
OVP IS HIGH WHEN WALL ADAPTER
VOLTAGE > 6V
Figure 7
441312fb
14
LTC4413-1/LTC4413-2
PACKAGE DESCRIPTION
DD Package
10-Lead Plastic DFN (3mm × 3mm)
(Reference LTC DWG # 05-08-1699)
0.675 ±0.05
3.50 ±0.05
1.65 ±0.05
2.15 ±0.05 (2 SIDES)
PACKAGE
OUTLINE
0.25 ± 0.05
0.50
BSC
2.38 ±0.05
(2 SIDES)
RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS
3.00 ±0.10
(4 SIDES)
R = 0.115
TYP
6
0.38 ± 0.10
10
1.65 ± 0.10
(2 SIDES)
PIN 1
TOP MARK
(SEE NOTE 6)
(DD) DFN 1103
5
0.200 REF
1
0.25 ± 0.05
0.50 BSC
0.75 ±0.05
0.00 – 0.05
2.38 ±0.10
(2 SIDES)
BOTTOM VIEW—EXPOSED PAD
NOTE:
1. DRAWING TO BE MADE A JEDEC PACKAGE OUTLINE M0-229 VARIATION OF (WEED-2).
CHECK THE LTC WEBSITE DATA SHEET FOR CURRENT STATUS OF VARIATION ASSIGNMENT
2. DRAWING NOT TO SCALE
3. ALL DIMENSIONS ARE IN MILLIMETERS
4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE
MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE
5. EXPOSED PAD SHALL BE SOLDER PLATED
6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE
TOP AND BOTTOM OF PACKAGE
441312fb
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
15
LTC4413-1/LTC4413-2
TYPICAL APPLICATION
Automatic Switchover from a Battery to a Wall Adapter with Soft-Start Overvoltage Protection
FDR8508
WALL
ADAPTER
INPUT
INA
C1
10μF
C2
10nF
OUTA
D1
OPTIONAL
IDEAL
VCC
RSTAT
470k
RENBA
560k
0.1μF
D2
5.6V
1Ω
ENBA
STAT
LTC4413-2
OVI
GND
STAT
OVP
OUTB
OVP
ENBB
INB
BAT
+
COUT
4.7μF
IDEAL
TO LOAD
441312 F07
C1: C0805C106K8PAC
C2: C0403C103K8PAC
COUT: C1206C475K8PAC
STAT IS HIGH WHEN WALL ADAPTER IS
SUPPLYING LOAD CURRENT
OVP IS HIGH WHEN WALL ADAPTER
VOLTAGE > 6V
RELATED PARTS
PART NUMBER
DESCRIPTION
COMMENTS
LTC1558/LTC1559
Backup Battery Controller with Programmable Output
Adjustable Backup Voltage from 1.2V NiCd Button Cell, Includes Boost
Converter
LTC1998
2.5μA, 1% Accurate Programmable Battery Detector
Adjustable Trip Voltage/Hysteresis, ThinSOTTM
LTC4054
800mA Standalone Linear Li-Ion Battery Charger with
Thermal Regulation in ThinSOT
No External MOSFET, Sense Resistor or Blocking Diode Required,
Charge Current Monitor for Gas Guaging, C/10 Charge Termination
LTC4350
Hot Swappable Load Share Controller
Allows N + 1 Redundant Supply, Equally Loads Multiple Power
Supplies Connected in Parallel
LTC4411
2.6A Low Loss Ideal Diode in ThinSOT
No External MOSFET, Automatic Switching Between DC sources,
Simplified Load Sharing
LTC4412/LTC4412HV PowerPath Controller in ThinSOT
More Efficient than Diode OR’ing, Automatic Switching Between DC
Sources, Simplified Load Sharing, 3V ≤ VIN ≤ 28V, 3V ≤ VIN ≤ 36V (HV)
LTC4413
Dual 2.6A, 2.5V to 5.5V, Ideal Diodes in 3mm × 3mm DFN Lower Quiescent Current with Slower Response Time
LTC4414
36V, Low Loss PowerPath Controller for Large PFETs
Drives Large QG PFETs, Very Low Loss Replacement for Power Supply
O’Ring Diodes, 3.5V to 36V AC/DC Adapter Voltage Range, 8-Lead
MSOP Package
ThinSOT is a trademark of Linear Technology Corporation.
441312fb
16 Linear Technology Corporation
LT 0907 REV B • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 ● FAX: (408) 434-0507
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