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LTC4413 Dual 2.6A, 2.5V to 5.5V, Ideal Diodes in 3mm x 3mm DFN
FEATURES

DESCRIPTIO
2-Channel Ideal Diode ORing or Load Sharing Low Loss Replacement for ORing Diodes Low Forward ON Resistance (100m Max at 3.6V) Low Reverse Leakage Current (1A 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-Off to Protect Against Inductive Source Impedance-Induced Voltage Spiking Low Quiescent Current Status Output to Indicate if Selected Channel is Conducting Programmable Channel ON/OFF Low Profile (0.75mm) 10-Lead 3mm x 3mm DFN Package
The LTC(R)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 100m 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 40A 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 1A 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 3. 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 9A 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.
APPLICATIO S

Battery and Wall Adapter Diode ORing in Handheld Products Backup Battery Diode ORing Power Switching USB Peripherals Uninterruptable Supplies
, LTC and LT are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners.
TYPICAL APPLICATIO
ENBA GND ENBB WALL ADAPTER (0V TO 5.5V) INB 10F
LTC4413 vs 1N5817 Schottky
2000
VCC LTC4413 STAT OUTB 470k STAT IS HIGH WHEN BAT IS SUPPLYING LOAD CURRENT
1500
IOUT (mA)
1000 1N5817
CONTROL CIRCUIT INA BAT OUTA 4.7F
4413 TA01
500
TO LOAD
0 0 100 200 VFWD (mV) 300 400
4413 TA01b
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LTC4413
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LTC4413
ABSOLUTE MAXIMUM RATINGS
(Note 1)
PACKAGE/ORDER INFORMATION
TOP VIEW INA ENBA GND ENBB INB 1 2 3 4 5 11 10 OUTA 9 STAT 8 NC 7 NC 6 OUTB
INA, INB, OUTA, OUTB, STAT, ENBA, ENBB Voltage ................................... -0.3V to 6V Operating Temperature Range ................ - 40C to 85C Storage Temperature Range ................. - 65C to 125C Continuous Power Dissipation (Derate 25mW/C Above 70C) ....................... 1500mW
ORDER PART NUMBER LTC4413EDD DD PART MARKING LBGN
DD PACKAGE 10-LEAD (3mm x 3mm) PLASTIC DFN
TJMAX = 125C, JA = 40C/W (4-LAYER PCB) EXPOSED PAD (PIN 11) IS GND MUST BE SOLDERED TO PCB
Consult LTC Marketing for parts specified with wider operating temperature ranges.
ELECTRICAL CHARACTERISTICS
SYMBOL VIN, VOUT UVLO IQF ILEAK IQRGND IQROUTA PARAMETER Operating Supply Range for Channel A or B UVLO Turn-On Rising Threshold UVLO Turn-Off Falling Threshold
The indicates specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25C. (Notes 2, 6)
CONDITIONS VIN and/or VOUT Must be in This Range for Proper Operation Max (VINA, VINB, VOUTA, VOUTB) Max (VINA, VINB, VOUTA, VOUTB)

MIN 2.5
TYP
MAX 5.5 2.4
UNITS V V V A A A A
1.7 25 -1 0.5 22 30 2 30 23
Quiescent Current in Forward Regulation (Note 3) VINA = 3.6V, IOUTA = -100mA, VINB = 0V, IOUTB = 0mA Current Drawn from or Sourced into IN when VOUT is Greater than VIN Quiescent Current While in Reverse Turn-Off, Measured via GND Quiescent Current While in Reverse Turn-Off, Current Drawn from VOUTA when OUTA Supplies Chip Power Quiescent Current While in Reverse Turn-Off, Current Drawn from VOUTA when OUTB Supplies Chip Power Quiescent Current with Both ENBA and ENBB High Reverse Turn-Off Voltage (VOUT - VIN) Forward Voltage Drop (VIN - VOUT) at IOUT = -1mA On Resistance, RFWD Regulation (Measured as V/I) On Resistance, RON Regulation (Measured as V/I at IIN = 1A) PowerPathTM Turn-Off Time VIN = 3.6V, VOUT = 5.5V (Note 6) VINA, VINB, VOUTB < VOUTA = 5.5V, VSTAT = 0V VINA, VINB, VOUTB < VOUTA = 5.5V
17
IQROUTB
VINA, VINB, VOUTA < VOUTB = 5.5V
2
3
IQOFF VRTO VFWD RFWD RON tOFF
VINA = VINB = 3.6V, VENBA and VENBB High, VSTAT = 0V VIN = 3.6V VIN = 3.6V VIN = 3.6V, IOUT = -100mA VIN = 3.6V, IOUT = -500mA (Note 5) VIN = 3.6V, IOUT = -1.5A (Note 5) VIN = 3.6V, IOUT = -100mA
20 -5
27 10
28
38 140 100
140 4
200
PowerPath is a trademark of Linear Technology Corporation.
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WW
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A
A mV mV m m m s
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LTC4413
ELECTRICAL CHARACTERISTICS
SYMBOL IOC IQOC PARAMETER Current Limit Quiescent Current While in Overcurrent Operation STAT Off Current STAT Sink Current STAT Pin Turn-On Time STAT Pin Turn-Off Time ENB Inputs Rising Threshold Voltage ENB Inputs Falling Threshold Voltage ENB Inputs Hysteresis ENB Inputs Pull-Down Current Short-Circuit Response
The indicates specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25C. (Notes 2, 6)
CONDITIONS VINX = 3.6V (Notes 4, 5) VINX = 3.6V, IOUT = 1.9A (Notes 4, 5) MIN 1.8 150 300 TYP MAX UNITS A A
STAT Output ISOFF ISON tS(ON) tS(OFF) ENB Inputs VENBIH VENBIL VENBHYST IENB VENB Rising VENB Falling VENBHYST = (VENBIH - VENBIL) VOUT < VIN = 3.6V, VENB > VENBIL

Shutdown VIN > VOUT, VCTL < VIL, IOUT < IMAX
-1 7
0 9 1 1 540
1 13
A A s s
600
mV mV mV
400 1.5
460 90 3 4.5
A
Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: The LTC4413 is guaranteed to meet performance specifications from 0C to 70C. Specifications over the -40C to 85C 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.
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: 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.
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LTC4413 TYPICAL PERFOR A CE CHARACTERISTICS
IQF vs ILOAD
200 120C 80C 40C 0C -40C IQF (A) 200 120C 80C 40C 0C -40C
160
IQF (A)
IQF (A)
120
80
40
0 100E-6
1E-3
10E-3 100E-3 ILOAD (A)
IOC vs Temperature (VIN = 3.5V)
4 2.20 2.15
3
IOC (A)
2.05 2.00 UVLO TURN-OFF 1.95 1.90
RFWD (m)
UVLO (V)
2
1 -40
0
40 80 TEMPERATURE (C)
RFWD vs Temperature (VIN = 3.5V)
160 140 120 RFWD IOUT = 1A RFWD IOUT = 100mA 100 80 RFWD IOUT = 500mA 60 40 20 0 -60 -20 100 60 TEMPERATURE (C) 20 140
4413 G07
VFWD (mV) AND RFWD (m)
VFWD (mV) AND RFWD (m)
RFWD (m)
4
UW
1E+0
4413 G01
IQF vs ILOAD
80
IQF vs Temperature
IQF AT 1A 60
160
120
40 IQF AT 100mA 20
80
40
0 10E+0
0
0.50
1
1.50 ILOAD (A)
2
2.50
3
0 -40
0
40 TEMPERATURE (C)
80
120
4413 G03
4413 G02
UVLO Thresholds vs Temperature
120 100 UVLO TURN-ON 2.10 80 60
RFWD vs VIN at ILOAD = 500mA
120C 80C 40C 0C -40C 40 20 0
120
4413 G04
1.85 -40
0
40 TEMPERATURE (C)
80
120
4413 G05
2.5
3.5 VINA (V)
4.5
5.5
4413 G06
VFWD and RFWD vs ILOAD
300 250 200 150 RFWD 100 50 0 300 120C 80C 40C 0C -40C VFWD 250 200 150 100 50 0 0 500 1000 1500 2000 IOUT (mA) 2500 3000
VFWD and RFWD vs ILOAD
120C 80C 40C 0C -40C RFWD VFWD
1
10
100 ILOAD (mA)
1000
10000
4413 G09
4413 G08
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LTC4413 TYPICAL PERFOR A CE CHARACTERISTICS
VFWD vs ILOAD (VIN = 3.5V)
300 250 200 120C 80C 40C 0C -40C CH4 150 100 50 0 1 10 100 ILOAD (mA) 1000 10000
4413 G10
VFWD (mV)
ENB Threshold vs Temperature
550 VIH 500
ENB HYSTERESIS (mV)
ENB THRESHOLD (mV)
450 VIL 400
350
300 -40
0
- ILEAK vs Temperature at VREVERSE = 5.5V
10E-6
10E-6
1E-6 -ILEAK (A)
-ILEAK (A)
100E-9
10E-9
1E-9 -40
0
UW
ENB Turn-On
CH4
CH4 CH2 CH1 CH3
ENB Turn-Off
CH3 CH2
CH3 CH2 CH1
CH1
400s/DIV
4413 G11
20s/DIV CH4 = IOUT (200mA/DIV) CH3 = VOUT (2V/DIV) CH2 = VSTAT (2V/DIV) CH1 = VENBA (500mV/DIV)
4413 G12
CH4 = IOUT (500mA/DIV) CH3 = VOUT (2V/DIV) CH2 = VSTAT (2V/DIV) CH1 = VENBA (500mV/DIV)
ENB Hysteresis vs Temperature
120 100 80 60 40 20 0 -40
80 40 TEMPERATURE (C)
120
4413 G13
0
40 80 TEMPERATURE (C)
120
4413 G14
- ILEAK vs VREVERSE
80C 40C 0C -40C
1E-6
100E-9
10E-9
1E-9
40 80 TEMPERATURE (C)
120
4413 G15
0
1
2 3 VREVERSE (V)
4
5
4413 G16
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LTC4413
PI FU CTIO S
INA (Pin 1): Primary Ideal Diode Anode and Positive Power Supply. Bypass INA with a ceramic capacitor of at least 1F. 1 snub resistors in series with a capacitor and higher valued capacitances are recommended when large inductances are in series with this input. This pin can be grounded when not used. ENBA (Pin 2): Enable Low for Diode A. Weak (3A) 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, 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 (3A) 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 1F. 1 snub resistors in series with a capacitor and higher valued capacitances are recommended when large inductances are in series with this input. This pin can be grounded when not used. OUTB (Pin 6): Secondary Ideal Diode Cathode and Output. Bypass OUTB with a high (1m min) ESR ceramic capacitor of at least 4.7F. 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 (9A) pulldown 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 (1m min) ESR ceramic capacitor of at least 4.7F. This pin must be left floating when not in use.
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LTC4413
BLOCK DIAGRA
1
INA OVER CURRENT
O.5V ENBA 2
VOFF ENA
3A
3
GND
5
INB OVER CURRENT
-+
O.5V ENBB 4
VOFF ENB
3A
+ -
+ -
-
-
+
+
W
OUTA 10
-+
PA UVLO ENA ENB OUTA (MAX) OUTB (MAX) STB VGATEA 9A AENA A OVERTEMP BENA STAT 9 OVERTEMP AENA
+ + -
BENA
-
+
-
OUTB
6
PB
VGATEB
B
+
-
4413 F01
Figure 1
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LTC4413
OPERATIO
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) will pull 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 will turn on PA. As VOUTA is pulled up to a forward voltage drop (VFWD) of 20mV below VINA, the LTC4413 will regulate VGATEA to maintain the small forward voltage drop. The system is now in forward regulation and the load at VOUTA will be powered from the supply at VINA. As the load current varies, VGATEA will be 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 will behave as a fixed resistor with resistance RON, whereby the forward voltage will increase slightly with increased load current. As the magnitude of IOUT increases further (such that ILOAD > IOC), the LTC4413 will fix 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.
IOC SLOPE 1/RON
CURRENT (A)
IFWD LTC4413 SCHOTTKY DIODE
SLOPE 1/RFWD
0 0 FORWARD VOLTAGE (V)
4413 F02
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If another supply is provided at VINB, the LTC4413 will likewise regulate the gate voltage on PB to maintain the output voltage VOUTB just below the input voltage VINB. If this alternate supply, VINB, exceeds the voltage at VINA, the LTC4413 will select 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 will sense the increased voltage at VOUTA and amplifier A will increase the voltage VGATEA, reducing the current through PA. When VOUTA is higher than VINA + VRTO, VGATEA will be pulled up to VDD, which will turn off PA. The internal power source for the LTC4413 (VDD) will then be 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 will sink 9A 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 will have its gate voltage 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 3A pull-down current on the ENB pins will ensure a low level at these inputs if left floating. Overcurrent and Short-Circuit Protection During an overcurrent condition, the output voltage will droop 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 will take some time to 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
Figure 2
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LTC4413
OPERATIO
occurs. During overcurrent operation, the power consumption of the LTC4413 will be 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 150C. An overtemperature condition will cause 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 140C, the amplifiers will turn on and revert to normal operation. Note that prolonged operation under overtemperature conditions will degrade reliability. 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.
Table 1. Mode Control
ENB1 Low Low High High ENB2 Low High Low High STATE Diode OR (NB: The Two Outputs are Not Connected Internal to the Device) Diode A = Enabled, Diode B = Disabled Diode A = Disabled, Diode B = Enabled All 0ff (Low Power Standby)
APPLICATIO S I FOR ATIO
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.
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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
ENB1 Low ENB2 Low CONDITIONS Diode A Forward Bias, Diode B Forward Bias Diode A Forward Bias, Diode B Reverse Bias Diode A Reverse Bias, Diode B Forward Bias Diode A Reverse Bias, Diode B Reverse Bias Low High Diode A Forward Bias, Diode B Disabled Diode A Reverse Bias, Diode B Disabled High Low Diode A Disabled, Diode B Forward Bias Diode A Disabled Diode B Reverse Bias High High Diode A Disabled, Diode B Disabled STAT ISNK = 0A ISNK = 0A ISNK = 9A ISNK = 9A ISNK = 0A ISNK = 9A ISNK = 0A ISNK = 9A ISNK = 9A
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 will provide the load current until it has discharged to the voltage of the other battery. The load will then be shared between the two batteries according to the capacity of each battery. The higher capacity battery will provide proportionally higher
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LTC4413
APPLICATIO S I FOR ATIO
MP1 FDR8508 WALL ADAPTER R1 1000k R2 200k 2 4 3,11 C1 10F ENBA ENBB STAT
9 RSTAT 470k TO LOAD
BATA 1-CELL Li-Ion BATB 1-CELL Li-Ion
GND LTC4413 IDEAL OUTA 10 1 INA IDEAL 5 INB OUTB 6
C1:C1206C106K8PAC C2:C1206C475K8PAC
C2 4.7F
4413 F03
Figure 3
current to the load. When a wall adapter input is applied, the voltage divider formed by R1 and R2 will disable the LTC4413, causing the STAT pin voltage to fall, turning on MP1. At this point the load will be 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 will droop until the voltage divider turns on the LTC4413, at which point the batteries will 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 4 illustrates an application circuit for microcontroller monitoring and control of two power sources. The
RSTAT 470k MICROCONTROLLER 2 4 3,11 ENBA ENBB STAT STAT 9
PRIMARY POWER AUX POWER
GND LTC4413 IDEAL OUTA 10 1 INA IDEAL 5 INB OUTB 6
CA 10F CB 10F
4413 F04
Figure 4
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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. Automatic Switchover from a Battery to an Auxiliary Supply or a Wall Adapter 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 (R4 and R5). 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 will forward bias, pulling the output voltage above the BAT voltage. The LTC4413 will sense a reverse voltage of as little as 10mV and turn off the ideal diode between INA and OUTA. This will cause the STAT voltage to fall, turning on MP1. The load will then draw current from the wall adapter, and the battery will be disconnected from the load. If the AUX is not present when the wall adapter is removed, the load voltage will droop until the BAT voltage exceeds the load voltage. The LTC4413 will sense that the BAT voltage is greater, causing the STAT voltage to rise, disabling MP1; the BAT will then provide power to the load.
MP1 FDR8508 WALL ADAPTER C1 10F R1 1 R2 1000k 4 R3 100k ENBB STAT LTC4413 9 RSTAT 470k IDEAL OUTA 10 1 INA GND IDEAL 5 INB OUTB 6 C2 4.7F ENBA C1:C0805C106K8PAC C2:C1206C475K8PAC
4413 F05
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BAT
3,11
TO LOAD
AUX ADAPTER
R4 1000k 2 R5 500k
TO LOAD
C1 4.7F
Figure 5
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LTC4413
APPLICATIO S I FOR ATIO
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 will fall and MP1 will conduct allowing the wall adapter to power the load. When the wall adapter is removed while the AUX supply is present, the load voltage will fall until the voltage divider at the ENBB pin falls through its turn-on threshold. Once this occurs, the LTC4413 will automatically connect 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. When an AUX supply is attached, the voltage divider at ENBA will disconnect the battery from the load, and the auxiliary supply will provide 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. 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
STAT IS HIGH 470k WHEN BAT1 IS CHARGING
BATTERY CHARGER INPUT
LTC4413 9 STAT IDEAL OUTA 10 1 INA IDEAL 5 INB OUTB 6 2 4 3,11 ENBA ENBB GND
4413 F06
LOAD1 BAT1 LOAD2 BAT2
Figure 6
LTC4413 9 STAT IDEAL OUTA 10 1 INA 1-CELL Li-Ion 2 4 3,11 ENBA ENBB
LTC4059 VCC BAT R2 100k Li CC GND WALL ADAPTER
ENB PROG
C1: C0805C106K8PAC C2: C1206C475K8PAC
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.
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current until both battery voltages are equal, then both will be charged. While both batteries are charging simultaneously, the higher capacity battery will get proportionally higher current from the charger. For Li-Ion batteries, both batteries will 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. Automatic Switchover from a Battery to a Wall Adapter and Charger 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 will be high, thereby disabling the battery charger. If a wall adapter of a higher voltage than the battery is connected to INB, the load voltage will rise as the second ideal diode conducts. As soon as the OUTA voltage exceeds INA voltage, the BAT will be disconnected from the load and the STAT voltage will fall, turning on the LTC4059 battery charger and beginning a charge cycle. If the wall adapter is removed, the voltage at INB will collapse until it is below the load voltage. When this occurs, the LTC4413 will automatically reconnect the battery to the load and the STAT voltage will rise, 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.
R1 560k GND IDEAL 5 INB OUTB 6 C1 10F TO LOAD C2 4.7F
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Figure 7
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LTC4413
PACKAGE DESCRIPTIO U
DD Package 10-Lead Plastic DFN (3mm x 3mm)
(Reference LTC DWG # 05-08-1699)
R = 0.115 TYP 6 0.675 0.05 0.38 0.10 10 3.00 0.10 (4 SIDES) PIN 1 PACKAGE TOP MARK OUTLINE (SEE NOTE 5) 5 0.25 0.05 0.50 BSC 2.38 0.05 (2 SIDES) RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS 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. ALL DIMENSIONS ARE IN MILLIMETERS 3. 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 4. EXPOSED PAD SHALL BE SOLDER PLATED 5. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE 0.200 REF 0.75 0.05 2.38 0.10 (2 SIDES) BOTTOM VIEW--EXPOSED PAD 1 0.25 0.05 0.50 BSC 1.65 0.10 (2 SIDES)
(DD10) DFN 0403
3.50 0.05 1.65 0.05 2.15 0.05 (2 SIDES)
0.00 - 0.05
RELATED PARTS
PART NUMBER LTC1558/LTC1559 LTC1998 LTC4054 LTC4055 LTC4350 LTC4351 LTC4411 DESCRIPTION Backup Battery Controller with Programmable Output 2.5A, 1% Accurate Programmable Battery Detector 800mA Standalone Linear Li-Ion Battery Charger with Thermal Regulation in ThinSOT USB Power Controller and Li-Ion Charger Hot Swappable Load Share Controller MOSFET Diode-OR Controller 2.6A Low Loss Ideal Diode in ThinSOT Load Sharing COMMENTS Adjustable Backup Voltage from 1.2V NiCd Button Cell, Includes Boost Converter Adjustable Trip Voltage/Hysteresis, ThinSOTTM No External MOSFET, Sense Resistor or Blocking Diode Required, Charge Current Monitor for Gas Gauging, C/10 Charge Termination Automatic Switchover, Charges 1-Cell Li-Ion Batteries Allows N + 1 Redundant Supply, Equally Loads Multiple Power Supplies Connected in Parallel 1.2V to 18V Input, Internal Boost Regulator for Driving N-Channel MOSFET No External MOSFET, Automatic Switching Between DC Sources, Simplified More Efficient than Diode ORing, Automatic Switching Between DC Sources, Simplified Load Sharing, 3V VIN 28V (3V VIN 36V for HV)
LTC4412/LTC4412HV PowerPath Controllers in ThinSOT ThinSOT is a trademark of Linear Technology Corporation.
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Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 FAX: (408) 434-0507
LT/TP 1104 1K * PRINTED IN THE USA
www.linear.com
(c) LINEAR TECHNOLOGY CORPORATION 2004

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