LTC3566/LTC3566-2
High Efficiency USB
Power Manager Plus 1A
Buck-Boost Converter
FEATURES
DESCRIPTION
POWER MANAGER
TheLTC®3566familyarehighlyintegratedpowermanage-
ment and battery charger ICs for Li-Ion/Polymer battery
applications. They include a high efficiency current lim-
ited 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
family’sswitchingpowermanagerautomaticallylimitsinput
current to a maximum of either 100mA or 500mA for USB
applications or 1A for adapter-powered applications.
■
High Efficiency Switching PowerPath™ Controller
with Bat-Track™ 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 I when Powered from BAT (<30μA)
Q
TheLTC3566family’sswitchinginputstagetransmitsnearly
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 family to provide more power to the
applicationandeasestheconstraintofthermalbudgetingin
smallspaces.TheLTC3566-2automaticallyreducescharge
1A BUCK-BOOST DC/DC
■
High Efficiency (1A I
)
OUT
■
■
■
■
2.25MHz Constant Frequency Operation
Low No-Load Quiescent Current (~13μA)
Zero Shutdown Current
current to maintain a regulated 3.6V V
during low bat-
OUT
Pin Control of All Functions
tery conditions; the LTC3566 does not. The synchronous
buck-boost DC/DC can provide up to 1A.
APPLICATIONS
The LTC3566 family 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.
■
HDD Based MP3 Players, PDA, GPS, PMP Products
Other USB Based Handheld Products
■
TYPICAL APPLICATION
LTC3566/LTC3566-2 USB Power Manager with 3.3V/1A Buck-Boost
Switching Regulator Efficiency to
System Load (POUT/PBUS
)
3.3μH
FROM AC
ADAPTER
100
90
80
70
60
50
40
30
20
10
0
V
=
OUT
V
SW
V
OUT
FROM USB
BAT + 300mV
TO OTHER
DC/DCs
BUS
10μF
4.7μF
CLPROG
PROG
GATE
BAT
3.01k
100k
OPTIONAL
BAT = 4.2V
0.1μF
2k
+
Li-Ion
1μF
3.3V/25mA
ALWAYS
ON LDO
BAT = 3.3V
NTC
LDO3V3
V
IN1
CHRG
CHRGEN
ILIM0
ILIM1
MODE
EN1
T
100k
LTC3566/LTC3566-2
SWAB1
2.2μH
1.3nF
1μF
SWCD1
3.3V/1A
HDD
V
I
= 5V
BUS
BAT
10x MODE
V
OUT1
DIGITAL CONTROL
= 0mA
324k
10μF
FB1
0.01
0.1
(A)
1
105k
GND
EXPOSED PAD
VC1
3566 TA01
I
OUT
3566 TA01b
3566fb
1