LTC3566 Datasheet, PDF (1/28 Pages) Linear Technology – High Effi ciency USB Power Manager Plus 1A Buck-Boost Converter

FEATURES
POWER MANAGER
■ _{High Efficiency Switching PowerPath}^TM _Controller
with Bat-Track^TM Adaptive Output Control
■ _{Programmable USB or Wall Input Current Limit}
(100mA/500mA/1A)
■ _{Full Featured Li-Ion/Polymer Battery Charger}
■ _{“Instant-On” Operation with Discharged Battery}
■ _{1.5A Maximum Charge Current}
■ _{Internal 180mΩ Ideal Diode Plus External Ideal Diode}
Controller Powers Load in Battery Mode
■ _{Low No-Load IQ when Powered from BAT (<30μA)}
1A BUCK-BOOST DC/DC
■ _{High Efficiency (1A IOUT)}
■ _{2.25MHz Constant Frequency Operation}
■ _{Low No-Load Quiescent Current (~13μA)}
■ _{Zero Shutdown Current}
■ _{Pin Control of All Functions}
APPLICATIONS
■ _{HDD Based MP3 Players, PDA, GPS, PMP Products}
■ _{Other USB Based Handheld Products}
LTC3566
High Efficiency USB
Power Manager Plus 1A
Buck-Boost Converter
DESCRIPTION
The LTC^®3566 is a highly integrated power management
and battery charger IC for Li-Ion/Polymer battery applica-
tions. It includes a high efficiency current limited switching
PowerPath manager with automatic load prioritization,
a battery charger, an ideal diode, and a high efficiency
synchronous buck-boost switching regulator. Designed
specifically for USB applications, the LTC3566’s switch-
ing power manager automatically limits input current to a
maximum of either 100mA or 500mA for USB applications
or 1A for adapter-powered applications.
The LTC3566’s switching input stage transmits nearly all of
the 2.5W available from the USB port to the system load
with minimal power wasted as heat. This feature allows the
LTC3566 to provide more power to the application and eases
the constraint of thermal budgeting in small spaces.
The synchronous buck-boost DC/DC can provide up to 1A.
The LTC3566 is available in a low profile 24-lead
4mm × 4mm QFN surface mount package.
L, LT, LTC and LTM 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, 6404251.
TYPICAL APPLICATION
LTC3566 USB Power Manager with 3.3V/1A Buck-Boost
FROM AC
ADAPTER
FROM USB
4.7μF
100k
3.01k
0.1μF
2k
V_BUS
CLPROG
PROG
3.3μH
SW
V_OUT
GATE
BAT
T 100k
DIGITAL CONTROL
NTC
CHRG
CHRGEN
ILIM0
ILIM1
MODE
EN1
GND
LTC3566
LDO3V3
V_IN1
SWAB1
SWCD1
V_OUT1
EXPOSED PAD
FB1
VC1
3566 TA01
V_OUT =
BAT + 300mV
10μF
TO OTHER
DC/DCs
OPTIONAL
+
Li-Ion
1μF
3.3V/25mA
ALWAYS
ON LDO
2.2μH
324k
1.3nF _105k
1μF
3.3V/1A
HDD
10μF
Switching Regulator Efficiency to
System Load (P_OUT/P_BUS)
100
90
80
70 ^{BAT = 4.2V}
60
BAT = 3.3V
50
40
30
20
10
0
0.01
V_BUS = 5V
I_BAT = 0mA
10x MODE
0.1
I_OUT (A)
1
3566 TA01b
3566fa
1