FEATURES
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LTC3577/LTC3577-1
Highly Integrated
6-Channel Portable PMIC
DESCRIPTION
The LTC
®
3577 is a highly integrated power management
IC for single cell Li-Ion/Polymer battery applications. It
includes a PowerPath manager with automatic load priori-
tization, a battery charger, an ideal diode, input overvoltage
protection and numerous other internal protection features.
The LTC3577 is designed to accurately charge from current
limited supplies such as USB by automatically reducing
charge current such that the sum of the load current and
the charge current does not exceed the programmed input
current limit (100mA or 500mA modes). The LTC3577
reduces the battery voltage at elevated temperatures to
improve safety and reliability. Efficient high current charg-
ing from supplies up to 38V is available using the on-chip
Bat-Track controller. The LTC3577 also includes a push-
button input to control the three synchronous step-down
switching regulators and system reset. The onboard LED
backlight boost circuitry can drive up to 10 series LEDs
and includes versatile digital dimming via I
2
C input. The
I
2
C input also controls two 150mA LDOs as well as other
operating modes and status read back. The LTC3577 is
available in a low profile 4mm
×
7mm
×
0.75mm 44-pin
QFN package.
L,
LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. PowerPath and Bat-Track are trademarks of Linear Technology
Corporation. All other trademarks are the property of their respective owners. Protected by U.S.
Patents including 6522118, 6700364, 7511390, 5481178, 6580258. Other Patents Pending.
Full Featured Li-Ion/Polymer Charger/PowerPath™
Control with Instant-On Operation
Triple Adjustable High Efficiency Step-Down
Switching Regulators (800mA, 500mA, 500mA I
OUT
)
6μA Battery Drain Current in Hard Reset
Bat-Track™ Control for External HV Buck DC/DCs
I
2
C Adjustable SW Slew Rates for EMI Reduction
High Temperature Battery Voltage Reduction
Improves Safety and Reliability
Overvoltage Protection for USB (V
BUS
)/Wall Inputs
Provides Protection to 30V
Integrated 40V Series LED Backlight Driver with 60dB
Brightness Control and Gradation via I
2
C
1.5A Maximum Charge Current with Thermal Limiting
Battery Float Voltage: 4.2V (LTC3577)
4.1V (LTC3577-1)
Pushbutton On/Off Control with System Reset
Dual 150mA Current Limited LDOs
Small 4mm
×
7mm 44-Pin QFN Package
APPLICATIONS
n
n
n
n
PNDs, DMB/DVB-H; Digital/Satellite Radio;
Media Players
Portable Industrial/Medical Products
Universal Remotes, Photo Viewers
Other USB-Based Handheld Products
TYPICAL APPLICATION
HV SUPPLY
8V TO 38V
(TRANSIENTS TO 60V)
OPTIONAL
USB
100mA/500mA
1000mA
EFFICIENCY (%)
V
OUT
OVERVOLTAGE
PROTECTION
CHARGE
2
0V
CC/CV
CHARGER
LTC3577/LTC3577-1
I
2
C PORT
NTC
HIGH VOLTAGE
BUCK DC/DC
LED Driver Efficiency 10 LEDs
90
80
70
60
MAX PWM
50
40
30
20
10
0
1.E-06
1.E-05
1.E-04 1.E-03 1.E-02
LED CURRENT (A)
1.E-01
CONSTANT
CURRENT
+
SINGLE CELL
Li-Ion
0.8V to 3.6V/150mA
0.8V to 3.6V/150mA
UP TO 10 LED
BOOST
0.8V to 3.6V/800mA
0.8V to 3.6V/500mA
0.8V to 3.6V/500mA
DUAL LDO
REGULATORS
LED BACKLIGHT WITH DIGITALLY
CONTROLLED DIMMING
TRIPLE HIGH EFFICIENCY
STEP-DOWN SWITCHING
REGULATORS WITH
PUSHBUTTON CONTROL
PB
3577 TA01b
3577 TA01a
3577f
1
LTC3577/LTC3577-1
TABLE OF CONTENTS
FEATURES/APPLICATIONS ..........................................................................................................................................1
ABSOLUTE MAXIMUM RATINGS .................................................................................................................................3
PACKAGE/ORDER INFORMATION ................................................................................................................................3
ELECTRICAL CHARACTERISTICS .......................................................................................................................... 4-10
TYPICAL PERFORMANCE CHARACTERISTICS .................................................................................................... 10-15
PIN FUNCTION ..................................................................................................................................................... 15-18
BLOCK DIAGRAM ......................................................................................................................................................18
PowerPath OPERATION ....................................................................................................................................... 19-29
LOW DROPOUT LINEAR REGULATOR OPERATION ............................................................................................. 29-30
STEP-DOWN SWITCHING REGULATOR OPERATION .......................................................................................... 30-33
LED BACKLIGHT/BOOST OPERATION.................................................................................................................. 33-36
I
2
C OPERATION ................................................................................................................................................... 37-42
PUSHBUTTON INTERFACE OPERATION ............................................................................................................... 42-46
LAYOUT AND THERMAL CONSIDERATIONS........................................................................................................ 47-48
TYPICAL APPLICATION ........................................................................................................................................ 49-50
PACKAGE DESCRIPTION ............................................................................................................................................51
RELATED PARTS ........................................................................................................................................................52
3577f
2
LTC3577/LTC3577-1
ABSOLUTE MAXIMUM RATINGS
(Notes 1, 2, 3)
PIN CONFIGURATION
44
CHRG
43 CLPROG
42 V
C
41
ACPR
40 V
BUS
39 V
OUT
38 BAT
I
LIM0
1
I
LIM1
2
LED_FS 3
WALL 4
SW3 5
V
IN3
6
FB3 7
OVSENS 8
LED_OV 9
DV
CC
10
SDA 11
SCL 12
OVGATE 13
PWR_ON 14
ON
15
45
37 IDGATE
36 PROG
35 NTC
34 NTCBIAS
33 SW1
32 V
IN12
31 SW2
30 V
INLD02
29 LDO2
28 LDO1
27 LDO1_FB
26 FB1
25 FB2
24 LDO2_FB
23 V
INLDO1
UFF PACKAGE
44-LEAD (7mm 4mm) PLASTIC QFN
T
JMAX
= 110°C,
θ
JA
= 45°C/W
EXPOSED PAD (PIN 45) IS GND, MUST BE SOLDERED TO PCB
TOP VIEW
V
SW
............................................................ –0.3V to 45V
V
BUS
, V
OUT
, V
IN12
, V
IN3
, V
INLDO1
, V
INLDO2
, WALL
t < 1ms and Duty Cycle < 1% .................. –0.3V to 7V
Steady State............................................. –0.3V to 6V
CHRG,
BAT, LED_FS, LED_OV, PWR_ON, WAKE,
PBSTAT, PG_DCDC, FB1, FB2, FB3, LDO1, LDO1_FB,
LDO2, LDO2_FB, DV
CC
, SCL, SDA ............... –0.3V to 6V
NTC, PROG, CLPROG,
ON,
I
LIM0
, I
LIM1
(Note 4)............................................–0.3V to V
CC
+ 0.3V
I
VBUS
, I
VOUT
, I
BAT
........................................................2A
I
SW3
(Continuous) ................................................850mA
I
SW2
, I
SW1
(Continuous) .......................................600mA
I
LDO1
, I
LDO2
(Continuous).....................................200mA
I
CHRG
, I
ACPR
, I
WAKE
, I
PBSTAT
, I
PG_DCDC
....................75mA
I
OVSENS
...................................................................10mA
I
CLPROG
, I
PROG
, I
LED_FS
, I
LED_OV
...............................2mA
Junction Temperature ........................................... 110°C
Operating Temperature Range.................. –40°C to 85°C
Storage Temperature Range................... –65°C to 125°C
ORDER INFORMATION
LEAD FREE FINISH
LTC3577EUFF#PBF
LTC3577EUFF-1#PBF
TAPE AND REEL
LTC3577EUFF#TRPBF
LTC3577EUFF-1#TRPBF
PART MARKING
3577
35771
PACKAGE DESCRIPTION
44-Lead (4mm
×
7mm) Plastic QFN
44-Lead (4mm
×
7mm) Plastic QFN
TEMPERATURE RANGE
–40°C to 85°C
–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/
PBSTAT 16
WAKE 17
SW 18
SW 19
SW 20
PG_DCDC 21
I
LED
22
3577f
3
LTC3577/LTC3577-1
ELECTRICAL CHARACTERISTICS
SYMBOL
V
BUS
I
BUS(LIM)
PARAMETER
Input Supply Voltage
Total Input Current (Note 5)
I
LIM0
= 0V, I
LIM1
= 0V (1x Mode)
I
LIM0
= 5V, I
LIM1
= 5V (5x Mode)
I
LIM0
= 5V, I
LIM1
= 0V (10x Mode)
1x, 5x, 10x Modes
I
LIM0
= 0V, I
LIM1
= 5V (Suspend Mode)
l
l
l
Power Manager
. The
l
denotes the specifications which apply over the
full operating temperature range, otherwise specifications are at T
A
= 25°C. V
BUS
= 5V, V
BAT
= 3.8V, I
LIM0
= I
LIM1
= WALL = 0V,
V
INLDO1
= V
INLDO2
= V
IN12
= V
IN3
= V
OUT
, R
PROG
= 2k, R
CLPROG
= 2.1k, unless otherwise noted.
CONDITIONS
MIN
4.35
80
450
900
90
475
950
0.42
0.042
1000
1x Mode
5x Mode
10x Mode
Rising Threshold
Falling Threshold
3.5
0.2
1.0
2.0
3.8
3.7
50
–50
200
3.9
100
TYP
MAX
5.5
100
500
1000
0.1
UNITS
V
mA
mA
mA
mA
mA
mA/mA
V
V
V
V
V
mV
mV
mΩ
Input Power Supply
I
BUSQ
h
CLPROG
V
CLPROG
Input Quiescent Current, POFF State
Ratio of Measured V
BUS
Current to
CLPROG Program Current
CLPROG Servo Voltage in Current
Limit
V
BUS
Undervoltage Lockout
V
UVLO
V
DUVLO
R
ON_ILIM
V
BUS
to V
OUT
Differential Undervoltage Rising Threshold
Lockout
Falling Threshold
Input Current Limit Power FET On-
Resistance (Between V
BUS
and V
OUT
)
V
BAT
Regulated Output Voltage
LTC3577
LTC3577, 0 ≤ T
A
≤ 85°C
LTC3577-1
LTC3577-1, 0 ≤ T
A
≤ 85°C
l
l
l
Battery Charger
V
FLOAT
4.179
4.165
4.079
4.065
950
465
180
4.200
4.200
4.100
4.100
1000
500
200
7
6
40
90
1.000
0.100
1000
V
BAT
< V
TRKL
V
BAT
Rising
V
BAT
Falling
Threshold Voltage Relative to V
FLOAT
Timer Starts when V
BAT
= V
FLOAT
– 50mV
V
BAT
< V
TRKL
40
2.5
–75
3.2
0.4
0.085
50
2.85
2.75
–100
4
0.5
0.1
200
110
60
3.0
–125
4.8
0.6
0.11
4.221
4.235
4.121
4.135
1050
535
220
15
27
100
160
V
V
V
V
mA
mA
mA
μA
μA
μA
μA
V
V
mA/mA
mA
V
V
mV
Hour
Hour
mA/mA
mΩ
°C
I
CHG
Constant-Current Mode Charge Current R
PROG
= 1k, Input Current Limit = 2A
R
PROG
= 2k, Input Current Limit = 1A
R
PROG
= 5k, Input Current Limit = 0.4A
Battery Drain Current, Hard Reset
Battery Drain Current, POFF State
Battery Drain Current, PON State
LDOs, and LED Backlight Disabled
PROG Pin Servo Voltage
V
BUS
= 0V, I
OUT
= 0μA
V
BAT
= 4.3V, Charger Time Out
V
BUS
= 0V
V
BUS
= 0V, I
OUT
= 0μA, No Load on
Supplies, Burst Mode Operation (Note 10)
V
BAT
> V
TRKL
V
BAT
< V
TRKL
I
BATQ_HR
I
BATQ_OFF
I
BATQ_ON
V
PROG,CHG
V
PROG,TRKL
PROG Pin Servo Voltage in Trickle
Charge
h
PROG
I
TRKL
V
TRKL
ΔV
RECHRG
t
TERM
t
BADBAT
h
C/10
R
ON_CHG
T
LIM
Ratio of I
BAT
to PROG Pin Current
Trickle Charge Current
Trickle Charge Rising Threshold
Trickle Charge Falling Threshold
Recharge Battery Threshold Voltage
Safety Timer Termination Period
Bad Battery Termination Time
Battery Charger Power FET On-
Resistance (Between V
OUT
and BAT)
Junction Temperature in Constant
Temperature Mode
End-of-Charge Indication Current Ratio (Note 6)
3577f
4
LTC3577/LTC3577-1
Power Manager
. The
l
denotes the specifications which apply over the
full operating temperature range, otherwise specifications are at T
A
= 25°C. V
BUS
= 5V, V
BAT
= 3.8V, I
LIM0
= I
LIM1
= WALL = 0V,
V
INLDO1
= V
INLDO2
= V
IN12
= V
IN3
= V
OUT
, R
PROG
= 2k, R
CLPROG
= 2.1k, unless otherwise noted.
SYMBOL
V
COLD
V
HOT
V
2HOT
I
NTC
I
BAT2HOT
V
BAT2HOT
Ideal Diode
V
FWD
R
DROPOUT
I
MAX
V
OVCUTOFF
V
OVGATE
I
OVSENSQ
t
RISE
Wall Adapter
V
ACPR
V
W
ΔV
W
I
QWALL
ACPR
Pin Output High Voltage
ACPR
Pin Output Low Voltage
Absolute Wall Input Threshold Voltage
Differential Wall Input Threshold
Voltage
Wall Operating Quiescent Current
I
ACPR
= 0.1mA
I
ACPR
= 1mA
V
WALL
Rising
V
WALL
Falling
V
WALL
– V
BAT
Falling
V
WALL
– V
BAT
Rising
I
WALL
+ I
VOUT
, I
BAT
= 0mA,
WALL = V
OUT
= 5V
I
LIM0
, I
LIM1
I
LIM0
, I
LIM1
I
LIM0
, I
LIM1
; V
PIN
= 1V
I
CHRG
= 10mA
V
BAT
= 4.5V, V
CHRG
= 5V
1.2
2
0.15
0
0.4
1
V
OUT
– 0.3
V
OUT
0
4.3
3.2
25
75
440
0.3
4.45
V
V
V
V
mV
mV
μA
Forward Voltage Detection
Diode On-Resistance, Dropout
Diode Current Limit
Overvoltage Protection Threshold
OVGATE Output Voltage
OVSENS Quiescent Current
OVGATE Time to Reach Regulation
I
OUT
= 10mA
I
OUT
= 200mA
(Note 7)
Rising Threshold, R
OVSENS
= 6.2k
Input Below V
OVCUTOFF
Input Above V
OVCUTOFF
V
OVSENS
= 5V
C
OVGATE
= 1nF
6.10
5
15
200
3.6
6.35
1.88 • V
OVSENS
0
40
2.5
6.70
12
25
mV
mΩ
A
V
V
V
μA
ms
PARAMETER
Cold Temperature Fault Threshold
Voltage
Hot Temperature Fault Threshold
Voltage
NTC Discharge Threshold Voltage
NTC Leakage Current
BAT Discharge Current
BAT Discharge Threshold
CONDITIONS
Rising NTC Voltage
Hysteresis
Falling NTC Voltage
Hysteresis
Falling NTC Voltage
Hysteresis
V
NTC
= V
BUS
= 5V
V
BAT
= 4.1V, NTC < V
TOO_HOT
I
BAT
< 0.1mA, NTC < V
TOO_HOT
MIN
75
34
24.5
–50
180
3.9
TYP
76
1.3
35
1.3
25.5
50
MAX
77
36
26.5
50
UNITS
%V
NTCBIAS
%V
NTCBIAS
%V
NTCBIAS
%V
NTCBIAS
%V
NTCBIAS
mV
nA
mA
V
NTC, Battery Discharge Protection
ELECTRICAL CHARACTERISTICS
Overvoltage Protection
3.1
0
100
Logic (I
LIM0
, I
LIM1
and
CHRG)
V
IL
V
IH
I
PD
V
CHRG
I
CHRG
Input Low Voltage
Input High Voltage
Static Pull-Down Current
CHRG
Pin Output Low Voltage
CHRG
Pin Input Current
0.4
V
V
μA
V
μA
3577f
5
Microchip MCU
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