LTC4413
Dual 2.6A, 2.5V to 5.5V,
Ideal Diodes in 3mm × 3mm DFN
Features
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Description
2-Channel Ideal Diode ORing or Load Sharing
Low Loss Replacement for ORing Diodes
Low Forward On-Resistance (100mΩ Max at 3.6V)
Low Reverse Leakage Current (1µA Max)
Small Regulated Forward Voltage (28mV Typ)
2.5V to 5.5V Operating Range
2.6A Maximum Forward Current
Internal Current Limit and Thermal Protection
Slow Turn-On/Off to Protect Against Inductive
Source Impedance-Induced Voltage Spiking
Ultralow Quiescent Current Consumption, Low
Power Alternative to the LTC4413-1
Status Output to Indicate if Selected Channel is
Conducting
Programmable Channel On/Off
Low Profile (0.75mm) 10-Lead 3mm × 3mm DFN
Package
Applications
Battery and Wall Adapter Diode ORing in Handheld
Products
n Backup Battery Diode ORing
n Power Switching
n USB Peripherals
n Uninterruptable Supplies
n
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
ThinSOT and PowerPath are trademarks of Linear Technology Corporation. All other trademarks
are the property of their respective owners.
The LTC®4413 contains two monolithic ideal diodes,
each capable of supplying up to 2.6A from input voltages
between 2.5V and 5.5V. Each ideal diode uses a 100mΩ
P-channel MOSFET that independently connects INA to
OUTA and INB to OUTB. During normal forward operation
the voltage drop across each of these diodes is regulated
to as low as 28mV. Quiescent current is less than 40µA
for diode currents up to 1A. If either of the output voltages
exceeds its respective input voltages, that MOSFET is
turned off and less than 1µA of reverse current will flow
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.
Two active-high control pins independently turn off the
two ideal diodes contained within the LTC4413, controlling the operation mode as described by Table 1. When
the selected channel is reverse biased, or the LTC4413 is
put into low power standby, a status signal indicates this
condition with a low voltage.
A 9µA open-drain STAT pin is used to indicate conduction
status. When terminated to a positive supply through a
470k resistor, the STAT pin can be used to indicate that the
selected diode is conducting with a high voltage. This signal
can also be used to drive an auxiliary P-channel MOSFET
power switch to control a third alternate power source
when the LTC4413 is not conducting forward current.
The LTC4413 is housed in a 10-lead DFN package.
Typical Application
VCC
WALL
ADAPTER
(0V TO 5.5V)
470k
LTC4413
ENBB
STAT
INB
OUTB
STAT IS HIGH WHEN
BAT IS SUPPLYING
LOAD CURRENT
10µF
1500
IOUT (mA)
ENBA
GND
LTC4413 vs 1N5817 Schottky
2000
LTC4413
1000
1N5817
CONTROL CIRCUIT
500
INA
BAT
OUTA
TO LOAD
4.7µF
0
4413 TA01
0
100
200
VFWD (mV)
300
400
4413 TA01b
4413fd
For more information www.linear.com/LTC4413
1
LTC4413
Absolute Maximum Ratings
Pin Configuration
(Note 1)
INA, INB, OUTA, OUTB, STAT,
ENBA, ENBB Voltage..................................... –0.3V to 6V
Operating Temperature Range.................. –40°C to 85°C
Storage Temperature Range.................... –65°C to 125°C
Junction Temperature (Note 4).............................. 125°C
Continuous Power Dissipation
(Derate 25mW/°C Above 70°C)..........................1500mW
TOP VIEW
10 OUTA
INA
1
ENBA
2
GND
3
ENBB
4
7 NC
INB
5
6 OUTB
9 STAT
11
8 NC
DD PACKAGE
10-LEAD (3mm × 3mm) PLASTIC DFN
TJMAX = 125°C, θJA = 40°C/W (4-LAYER PCB)
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
LTC4413EDD#PBF
LTC4413EDD#TRPBF
LBGN
10-Lead (3mm × 3mm) Plastic DFN
–40°C to 85°C
Consult LTC Marketing for parts specified with wider operating temperature ranges.
Consult LTC Marketing for information on non-standard lead based finish parts.
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 l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. (Notes 2, 6)
SYMBOL
PARAMETER
CONDITIONS
VIN , VOUT
Operating Supply Range for Channel A or B
VIN and/or VOUT Must Be in This Range
for Proper Operation
l
MIN
UVLO
UVLO Turn-On Rising Threshold
Max (VINA , VINB , VOUTA , VOUTB)
l
UVLO Turn-Off Falling Threshold
Max (VINA , VINB , VOUTA , VOUTB)
l
IQF
Quiescent Current in Forward Regulation (Note 3) VINA = 3.6V, IOUTA = –100mA, VINB = 0V,
IOUTB = 0mA
l
IQRIN
Quiescent Current While in Reverse
Turn-Off, Current Drawn from VIN
VIN = 3.6V, VOUT = 5.5V (Note 6)
l
IQRGND
Quiescent Current While in Reverse Turn-Off,
Measured Via GND
VINA = VINB = VOUTB = 0V, VOUTA = 5.5V,
VSTAT = 0V
IQROUTA
Quiescent Current While in Reverse Turn-Off,
Current Drawn from VOUTA When OUTA
Supplies Chip Power
VINA = VINB = VOUTB = 0V, VOUTA = 5.5V
IQROUTB
Quiescent Current While in Reverse Turn-Off,
Current Drawn from VOUTA When OUTB
Supplies Chip Power
IQOFF
Quiescent Current with Both ENBA
and ENBB High
TYP
2.5
MAX
UNITS
5.5
V
2.4
V
1.7
V
25
40
µA
0.5
2
µA
22
30
µA
l
17
31
µA
VINA = VINB = 0V, VOUTA < VOUTB = 5.5V
l
2
3
µA
VINA = VINB = 3.6V, VENBA and
VENBB High, VSTAT = 0V
l
20
31
µA
–1
4413fd
2
For more information www.linear.com/LTC4413
LTC4413
Electrical Characteristics
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. (Notes 2, 6)
SYMBOL
PARAMETER
CONDITIONS
ILEAK
VINA or VINB Current When VOUTA or VOUTB
Supplies Power
VIN = 0V, VOUT = 5.5V
MIN
–1
1
µA
VRTO
Reverse Turn-Off Voltage (VOUT – VIN)
VIN = 3.6V
–5
10
mV
VFWD
Forward Voltage Drop (VIN – VOUT)
at IOUT = –1mA
VIN = 3.6V
28
38
mV
RFWD
On-Resistance, RFWD Regulation
(Measured as ∆V/∆I)
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, IOUT = –1.0A (Note 5)
140
200
mΩ
tON
PowerPath™ Turn-On Time
VIN = 3.6V, from ENBA, ENBB Falling to IIN
Ramp Starting (Note 7)
50
µs
tOFF
PowerPath Turn-Off Time
VIN = 3.6V, IOUT = –100mA (Note 7)
4
µs
l
TYP
MAX
UNITS
Short-Circuit Response
IOC
Current Limit
VINX = 3.6V (Notes 4, 5)
IQOC
Quiescent Current While in
Overcurrent Operation
VINX = 3.6V, IOUT = 1.9A (Notes 4, 5)
1.8
A
ISOFF
STAT Off Current
Shutdown
ISON
STAT Sink Current
VIN > VOUT, VENBA < VENBIL , VENBB < VENBIL ,
IOUT < IMAX
tS(ON)
STAT Pin Turn-On Time
1
µs
tS(OFF)
STAT Pin Turn-Off Time
1
µs
150
300
µA
–1
0
1
µA
7
9
17
µA
STAT Output
l
ENB Inputs
VENBIH
ENBA, ENBB Inputs Rising Threshold Voltage
VENBA, VENBB Rising
l
VENBIL
ENBA, ENBB Inputs Falling Threshold Voltage
VENBA, VENBB Falling
l
400
VENBHYST
ENBA, ENBB Inputs Hysteresis
VENBHYST = (VENBIH – VENBIL)
IENB
ENBA, ENBB Inputs Pull-Down Current
VOUT < VIN = 3.6V, VENBA > VENBIL,
VENBB > VENBIL
l
1.5
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 is guaranteed to meet performance specifications
from 0°C to 85°C. Specifications over the –40°C to 85°C 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.
Note 4: This IC includes overtemperature protection that is intended
540
600
460
90
3
mV
mV
mV
4.5
µA
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: This 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.
Note 7: Guaranteed by design.
4413fd
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3
LTC4413
Typical Performance Characteristics
IQF vs ILOAD
120°C
80°C
40°C
0°C
–40°C
120
80
40
1E-3
10E-3 100E-3
ILOAD (A)
1E+0
60
120
80
0
10E+0
0
1
0.50
1.50
ILOAD (A)
2
2.50
0
–40
4413 G02
UVLO Thresholds vs Temperature
2.20
120
UVLO TURN-OFF
1.85
–40
0
40
TEMPERATURE (°C)
4413 G04
RFWD vs Temperature (VIN = 3.5V)
100
RFWD IOUT = 100mA
RFWD IOUT = 1A
80
RFWD IOUT = 500mA
60
40
20
0
–60
–20
20
100
60
TEMPERATURE (°C)
140
0
2.5
3.5
4.5
VIN (V)
4413 G05
300
VFWD (mV) AND RFWD (mΩ)
RFWD (mΩ)
120
–40°C
120
80
160
140
0°C
60
20
1.90
120
40°C
40
1.95
40
80
TEMPERATURE (°C)
4413 G03
80°C
2.05
2.00
120
120°C
80
RFWD (mΩ)
UVLO (V)
IOC (A)
2
80
RFWD vs VIN at ILOAD = 500mA
100
2.10
3
40
0
TEMPERATURE (°C)
UVLO TURN-ON
0
IQF AT 100mA
3
2.15
1
–40
40
20
4413 G01
IOC vs Temperature (VIN = 3.5V)
IQF vs Temperature
IQF AT 1A
40
0
100E-6
4
80
120°C
80°C
40°C
0°C
–40°C
160
IQF (µA)
IQF (µA)
160
IQF vs ILOAD
200
IQF (µA)
200
5.5
4413 G06
VFWD and RFWD vs ILOAD
120°C
80°C
40°C
0°C
–40°C
250
200
150
VFWD
RFWD
100
50
0
0
4413 G07
500
1000
1500 2000
IOUT (mA)
2500
3000
4413 G08
4413fd
4
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LTC4413
Typical Performance Characteristics
120°C
80°C
40°C
0°C
–40°C
250
200
300
VFWD
150
150
100
100
50
50
0
1
10
100
ILOAD (mA)
0
10000
1000
4413 G17
20µs/DIV
10
1
4413 G09
ENBA, ENBB Turn-On, 240µs to
Recover with 180mA Load
IN
200mV/DIV
OUT
200mV/DIV
IOUT
200mA/DIV
120°C
80°C
40°C
0°C
–40°C
200
RFWD
Response to 800mA Load Step
in 80µs
VFWD vs ILOAD (VIN = 3.5V)
250
VFWD (mV)
VFWD (mV) AND RFWD (mΩ)
300
VFWD and RFWD vs ILOAD
100
ILOAD (mA)
10000
1000
4413 G10
ENBA, ENBB Turn-Off, 16µs to
Disconnect IN from 180mA Load
ENBA, ENBB Threshold vs
Temperature
550
VOUTA, VOUTB
ENBA, ENBB
1V/DIV
OUTA, OUTB
1V/DIV
ENBA, ENBB
1V/DIV
VENBA, VENBB
IOUTA, IOUTB
500mA/DIV
IOUTA, IOUTB
100mA/DIV
4413 G12
4µs/DIV
4413 G11
100µs/DIV
VENBIH
ENBA, ENBB THRESHOLD (mV)
INA, INB
1V/DIV
OUTA, OUTB
1V/DIV
INA, INB
1V/DIV
500
450
VENBIL
400
350
300
–40
ENBA, ENBB Hysteresis vs
Temperature
10E-6
100
80
40
TEMPERATURE (°C)
120
4413 G13
– ILEAK vs Temperature at
VREVERSE = 5.5V
1E-6
80
–ILEAK (A)
ENBA, ENBB HYSTERESIS (mV)
120
0
100E-9
60
40
10E-9
20
0
–40
0
40
80
TEMPERATURE (°C)
120
1E-9
–40
4413 G14
0
40
80
TEMPERATURE (°C)
120
4413 G15
4413fd
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5
LTC4413
Typical Performance Characteristics
– ILEAK vs VREVERSE
Efficiency vs Load Current
80°C
40°C
0°C
–40°C
–ILEAK (A)
100E-9
10E-9
1E-9
500
0.98
EFFICIENCY (%)
1E-6
Power Loss LTC4413 vs 1N5817
600
1.00
POWER LOSS (mW)
10E-6
0.96
0.94
0.92
0
1
2
3
VREVERSE (V)
4
5
4413 G16
0.90
1.0E-3
400
300
1N5817
LTC4413
200
100
10.0E-3 100.0E-3
1.0E+0
LOAD CURRENT (A)
10.0E+0
1351 G13
0
1
500
1000
1500
ILOAD (mA)
2000
2500
4413 G19
Pin Functions
INA (Pin 1): Primary Ideal Diode Anode and Positive
Power Supply. Bypass INA with a ceramic capacitor of at
least 1µF. 1Ω snub resistors in series with a capacitor and
higher valued capacitances are recommended when large
inductances are in series with this input. Limit slew rate
on this pin to less than 0.5V/µs. This pin can be grounded
when not used.
ENBA (Pin 2): Enable Low for Diode A. Weak (3µA) pulldown. 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, weak pull-down
internal to the LTC4413.
GND (Pins 3, Exposed Pad Pin 11): Power and Signal
Ground for the IC. The exposed pad of the package, Pin 11,
must be soldered to PCB ground to provide both electrical
contact to ground and good thermal contact to the PCB.
ENBB (Pin 4): Enable Low for Diode B. Weak (3µA) pulldown. 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, weak pull-down
internal to the LTC4413.
INB (Pin 5): Secondary Ideal Diode Anode and Positive
Power Supply. Bypass INB with a ceramic capacitor of at
least 1µF. 1Ω snub resistors in series with a capacitor and
higher valued capacitances are recommended when large
inductances are in series with this input. Limit slew rate
on this pin to less than 0.5V/µs. This pin can be grounded
when not used.
OUTB (Pin 6): Secondary Ideal Diode Cathode and Output.
Bypass OUTB with a high (1mΩ min) ESR ceramic capacitor
of at least 4.7µF. Limit slew rate on this pin to less than
0.5V/µs. This pin must be left floating when not in use.
NC (Pin 7): No Internal Connection.
NC (Pin 8): No Internal Connection.
STAT (Pin 9): Status Condition Indicator. Weak (9µA)
pull-down current output. When terminated, STAT = high
indicates diode conducting.
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. This pin can also be
left floating or grounded.
OUTA (Pin 10): Primary Ideal Diode Cathode and Output.
Bypass OUTA with a high (1mΩ min) ESR ceramic capacitor
of at least 4.7µF. Limit slew rate on this pin to less than
0.5V/µs. This pin must be left floating when not in use.
4413fd
6
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LTC4413
Block Diagram
1
INA
OUTA
OVER CURRENT
PA
–+
UVLO
ENA
–
+
ENBA
+
VOFF
VGATEA
+
–
2
–
AENA
OVER TEMP
ENB
OUTA (MAX)
OUTB (MAX)
O.5V
10
ENA
BENA
OVER TEMP
STAT
STB
9
9µA
AENA
A
+
–
3µA
3
5
GND
INB
OUTB
OVER CURRENT
6
PB
–+
–
+
4
ENBB
+
VOFF
ENB
VGATEB
+
–
O.5V
–
BENA
B
+
–
3µA
4413 F01
Figure 1
4413fd
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7
LTC4413
Operation
The LTC4413 is described with the aid of the Block Diagram
(Figure 1). Operation begins when the power source at
VINA or VINB rises above the undervoltage lockout (UVLO)
voltage of 2.4V and either of the ENBA or ENBB control
pins is low. If only the voltage at the VINA pin is present, the
power source to the LTC4413 (VDD) will be 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 is pulled up to
a forward voltage drop (VFWD) of 20mV 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 with
resistance RON, whereby the forward voltage increases
slightly with increased load current. As the magnitude of
IOUT increases further (such that ILOAD > IOC), the LTC4413
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 2,
illustrating the LTC4413 forward voltage drop versus that
of a Schottky diode.
If another supply is provided at VINB, the LTC4413 likewise
regulates the gate voltage on PB to maintain the output
voltage VOUTB just below the input voltage VINB . If this
IOC
CURRENT (A)
SLOPE
1/RON
IFWD
LTC4413
SCHOTTKY
DIODE
SLOPE
1/RFWD
alternate supply, VINB , exceeds the voltage at VINA , the
LTC4413 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 senses 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 is pulled up to VDD , which
turns off PA. The internal power source for the LTC4413
(VDD) is then diverted to source 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 is drawn from VINA to sense the potential at VINA.
When the selected channel of the LTC4413 is in reverse
turn-off mode or both channels are disabled, the STAT pin
sinks 9µA of current (ISON) if connected.
Channel selection is accomplished using the two ENB pins,
ENBA and ENBB. For example with channel A, when the
ENBA input is asserted (high), PA’s gate voltage is pulled
to VDD at a controlled rate, limiting the turn-off time to
avoid voltage spiking at the input when being driven by an
inductive source impedance. A 3µA pull-down current on
the ENBA, ENBB pins ensures a low level at these inputs
if left floating.
Slow Response Time
The LTC4413-1 (or LTC4413-2) is recommended for
applications with demanding load step or fast slew rate
requirements. The LTC4413-1 and LTC4413-2 provide better load regulation in these environments at the expense
of higher quiescent current. The LTC4413 is optimized
for lower power consumption and should not be used in
high slew rate environments or when large and fast load
transients are anticipated.
Overcurrent and Short-Circuit Protection
0
0
FORWARD VOLTAGE (V)
4413 F02
Figure 2
During an overcurrent condition, the output voltage droops
as the load current exceeds the amount of current that
the LTC4413 can supply. At the time when an overcurrent
condition is first detected, the LTC4413 takes some time to
4413fd
8
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LTC4413
Operation
detect this condition before reducing the current to IMAX.
For short durations after the output is shorted, the
current may exceed IMAX . 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 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 causes the gate amplifiers (A
and B) as well as the two P-channel MOSFETs (PA and
PB) to be shut off. When the internal die temperature
cools to below 140°C, the amplifiers turn on and revert
to normal operation. Note that prolonged operation under
overtemperature conditions degrades reliability.
Table 1. Mode Control
ENBA
ENBB
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 0ff (Low Power Standby)
The function of the STAT pin depends on the mode that
has been selected. The following table 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 Funtion
ENBA
ENBB
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 = 9µA
Diode A Reverse Bias,
Diode B Reverse Bias
ISNK = 9µA
Diode A Forward Bias,
Diode B Disabled
ISNK = 0µA
Diode A Reverse Bias,
Diode B Disabled
ISNK = 9µA
Diode A Disabled,
Diode B Forward Bias
ISNK = 0µA
Diode A Disabled
Diode B Reverse Bias
ISNK = 9µA
Diode A Disabled,
Diode B Disabled
ISNK = 9µA
Channel Selection and Status Output
Two active-high control pins independently turn off the
two ideal diodes contained within the LTC4413, controlling the operation mode as described by Table 1. When
the selected channel is reverse biased, or the LTC4413 is
put into low power standby, the status signal indicates
this condition with a low voltage.
Low
High
High
High
Low
High
Applications Information
Introduction
The LTC4413 is intended for power control applications
that include low loss diode ORing, 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. The LTC4413 is
optimized for low quiescent power consumption at the
expense of transient response. For more demanding slew
rate or load transient applications, the pin compatible
LTC4413-1 is recommended.
Dual Battery Load Sharing with Automatic Switchover
to a Wall Adapter
An application circuit for dual battery load sharing with
automatic switchover of load from batteries to a wall adapter
is shown in Figure 3. When the wall adapter is not present,
whichever battery that has the higher voltage provides the
load current until it has discharged to the voltage of the
other battery. The load is then shared between the two
4413fd
For more information www.linear.com/LTC4413
9
LTC4413
Applications Information
microcontroller’s analog inputs (perhaps with the aid of a
resistor voltage divider) monitors each supply input and
the LTC4413 status, and then commands the LTC4413
through the two ENBA/ENBB control inputs.
MP1 FDR8508
WALL
ADAPTER
C1
10µF
R1
1000k
R2
200k
2
4
3,11
BATA
1-CELL Li-Ion
ENBA
ENBB
STAT
9
GND
LTC4413
IDEAL
OUTA 10
1 INA
Automatic Switchover from a Battery to an Auxiliary
Supply or a Wall Adapter
RSTAT
470k
TO
LOAD
IDEAL
5 INB
OUTB 6
BATB
1-CELL Li-Ion
C1:C1206C106K8PAC
C2:C1206C475K8PAC
C2
4.7µF
4413 F03
Figure 3
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 voltage divider formed by R1 and R2 disables the
LTC4413, causing the STAT pin voltage to fall, turning on
MP1. At this point the load is powered by the wall adapter
and both batteries may be removed without interrupting
the load voltage. When the wall adapter is removed, the
output voltage droops until the voltage divider turns on the
LTC4413, at which point the batteries revert to providing
load power. The status signal can also be used to provide
information as to whether the wall adapter (or BATB) is
supplying the load current.
Automatic PowerPath Control
Figure 5 illustrates an application for implementing the
function of automatic switchover from a battery to either
an auxiliary supply or to a wall adapter using the LTC4413.
The LTC4413 automatically senses the presence of a wall
adapter as the ENBB pin voltage is pulled higher than its
rising turn-off threshold of 550mV through resistive divider
(R2 and R3). This disables the AUX input from powering
the load. If the AUX is not present when a wall adapter is
attached (i.e., the BAT is supplying load current), as the
wall adapter voltage rises, the body diode in MP1 forward
biases, pulling the output voltage above the BAT voltage.
The LTC4413 senses a reverse voltage of as little as 10mV
and turns off the ideal diode between INA and OUTA. This
causes the STAT voltage to fall, turning on MP1. The load
then draws current from the wall adapter, and the battery is
disconnected from the load. If the AUX is not present when
the wall adapter is removed, the load voltage droops until
the BAT voltage exceeds the load voltage. The LTC4413
senses that the BAT voltage is greater, causing the STAT
voltage to rise, disabling MP1; the BAT then provides
power to the load.
Figure 4 illustrates an application circuit for microcontroller monitoring and control of two power sources. The
MICROCONTROLLER
2
4
3,11
PRIMARY
POWER
AUX
POWER
STAT
IDEAL
5 INB
OUTB 6
CB
10µF
R2
1000k 4
R3
100k
9
GND
LTC4413
IDEAL
OUTA 10
1 INA
CA
10µF
C1
10µF
R1
1Ω
STAT
ENBA
ENBB
RSTAT
470k
MP1 FDR8508
WALL
ADAPTER
BAT
TO
LOAD
AUX
ADAPTER
C1
4.7µF
4413 F04
Figure 4
ENBB
STAT
LTC4413
9
IDEAL
OUTA 10
1 INA
RSTAT
470k
3,11
GND
IDEAL
5 INB
OUTB 6
R4
1000k 2
R5
500k
ENBA
C2
4.7µF
TO
LOAD
4413 F05
C1:C0805C106K8PAC
C2:C1206C475K8PAC
Figure 5
4413fd
10
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LTC4413
Applications Information
If the AUX is present when a wall adapter is applied, as
the resistive divider to ENBB rises through the turn-off
threshold, the STAT pin voltage falls and MP1 conducts,
allowing the wall adapter to power the load. When the wall
adapter is removed while the AUX supply is present, the
load voltage falls until the voltage divider at the ENBB pin
falls through its turn-on threshold. Once this occurs, the
LTC4413 automatically connects the AUX supply to the load
when the AUX voltage exceeds the output voltage, causing
the STAT voltage to rise and disabling the external PFET.
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
20mV. This concept can apply to more than two batteries.
The STAT pin provides information as to when battery 1
is being charged. For intelligent control, the ENBA/ENBB
pin inputs can be used with a microcontroller as shown
in Figure 4.
When an AUX supply is attached, the voltage divider at
ENBA (R4 and R5) disconnects the battery from the load,
and the auxiliary supply provides load current, unless a
wall adapter is present as described earlier. If the auxiliary
supply is removed, the battery may again power the load,
depending on if a wall adapter is present.
Automatic Switchover from a Battery to a Wall
Adapter and Charger
Multiple Battery Charging
Figure 6 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
BATTERY
CHARGER
INPUT
LTC4413
9
STAT
IDEAL
OUTA 10
1 INA
STAT IS HIGH
470k WHEN BAT1
IS CHARGING
LOAD1
IDEAL
5 INB
OUTB 6
BAT1
2
BAT2
4
3,11
ENBA
ENBB
GND
4413 F06
Figure 6
LOAD2
Figure 7 illustrates the LTC4413 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 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 INB, the load voltage rises as
the second ideal diode conducts. As soon as the OUTA
voltage exceeds 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
the wall adapter is removed, the voltage at INB collapses
until it is below the load voltage. When this occurs, the
LTC4413 automatically reconnects the battery to the load
and the STAT voltage rises, disabling the LTC4059 battery
charger. 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.
4413fd
For more information www.linear.com/LTC4413
11
LTC4413
Package Description
Please refer to http://www.linear.com/designtools/packaging/ for the most recent package drawings.
DD Package
10-Lead Plastic DFN (3mm × 3mm)
(Reference LTC DWG # 05-08-1699 Rev C)
0.70 ±0.05
3.55 ±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 = 0.125
TYP
6
0.40 ±0.10
10
1.65 ±0.10
(2 SIDES)
PIN 1 NOTCH
R = 0.20 OR
0.35 × 45°
CHAMFER
PIN 1
TOP MARK
(SEE NOTE 6)
0.200 REF
0.75 ±0.05
0.00 – 0.05
5
1
(DD) DFN REV C 0310
0.25 ±0.05
0.50 BSC
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
4413fd
12
For more information www.linear.com/LTC4413
LTC4413
Revision History
(Revision history begins at Rev D)
REV
DATE
DESCRIPTION
D
07/15
Changed VENB to VENBA,B in electrical characteristics
PAGE NUMBER
3
Changed ENB to ENBA,B IN to INA,B and OUT to OUTA,B on plots 3 to 7
5
Added exposed pad to GND Pin Function label
6
Added sentence to paragraph prior to Slow Response section and added A,B references
8
Changed ENBA and ENBB on Tables 1 and 2
9
Added LTC4415 to Related Parts table
12
4413fd
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 representaFor more
information
www.linear.com/LTC4413
tion that the interconnection
of its circuits
as described
herein will not infringe on existing patent rights.
13
LTC4413
Typical Applications
LTC4413
9
STAT
IDEAL
OUTA 10
1 INA
LTC4059
VCC
BAT
ENB PROG
Li CC GND
WALL
ADAPTER
2
1-CELL
Li-Ion
R2
100k
4
3,11
R1
560k
ENBA
ENBB
GND
IDEAL
5 INB
OUTB 6
C1: C0805C106K8PAC
C2: C1206C475K8PAC
C1
10µF
C2
4.7µF
TO LOAD
4413 F07
Figure 7
Related Parts
PART NUMBER
DESCRIPTION
COMMENTS
LTC1558/LTC1559
Backup Battery Controller with Programmable Adjustable Backup Voltage from 1.2V NiCd Button Cell, Includes Boost Converter
Output
LTC1998
2.5µA, 1% Accurate Programmable Battery
Detector
Adjustable Trip Voltage/Hysteresis, ThinSOT™
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 Gauging, C/10 Charge Termination
LTC4055
USB Power Controller and Li-Ion Charger
Automatic Switchover, Charges 1-Cell Li-Ion Batteries
LTC4085
USB Power Manager with Ideal Diode
Controller and Li-Ion Charger
Charges Single Cell Li-Ion Batteries Directly from a USB Port, Thermal
Regulation, 200mΩ Ideal Diode with