LTC3566EUF-2#TRPBF Linear Technology, LTC3566EUF-2#TRPBF Datasheet - Page 14

• Manufacturer Part Number: LTC3566EUF-2#TRPBF
• Description: IC POWER MANAGER USB 24-QFN
• Manufacturer: Linear Technology

Specifications of LTC3566EUF-2#TRPBF

• Applications: Handheld/Mobile Devices
• Voltage - Supply: 4.35 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 24-QFN
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Supply: -

LTC3566/LTC3566-2
OPERATION
conductance is needed, an external P-channel MOSFET
transistor can be added from BAT to V
When an external P-channel MOSFET transistor is pres-
ent, the GATE pin of the LTC3566 family drives its gate for
automatic ideal diode control. The source of the external
P-channel MOSFET should be connected to V
drain should be connected to BAT. Capable of driving a
1nF load, the GATE pin can control an external P-channel
MOSFET transistor having an on-resistance of 40mΩ or
lower.
Suspend LDO
If the LTC3566 family is confi gured for USB suspend mode,
the switching regulator is disabled and the suspend LDO
provides power to the V
available to V
running down when the portable product has access to
a suspended USB port. Regulating at 4.6V, this LDO only
becomes active when the switching converter is disabled
(suspended). In accordance with the USB specifi cation, the
input to the LDO is current limited so that it will not exceed
the 500μA low power suspend specifi cation. If the load
14
OR WALL
ADAPTER
TO USB
21
2
BUS
I
V
SWITCH
CLPROG
BUS
1.188V
). This LDO will prevent the battery from
/N
AVERAGE INPUT
CURRENT LIMIT
CONTROLLER
OUT
–
+
pin (presuming there is power
GATE DRIVE
PWM AND
AVERAGE OUTPUT
OUT
VOLTAGE LIMIT
CONTROLLER
.
Figure 3. PowerPath Block Diagram
OUT
–
+
+
3.6V
and the
CONSTANT CURRENT
CONSTANT VOLTAGE
BATTERY CHARGER
0.3V
+ –
on V
current will come from the battery via the ideal diode.
3.3V Always-On Supply
The LTC3566 family includes a low quiescent current low
dropout regulator that is always powered. This LDO can be
used to provide power to a system pushbutton controller,
standby microcontroller or real time clock. Designed to
deliver up to 25mA, the always-on LDO requires at least
a 1μF low impedance ceramic bypass capacitor for com-
pensation. The LDO is powered from V
will enter dropout at loads less than 25mA as V
near 3.3V. If the LDO3V3 output is not used, it should be
disabled by connecting it to V
V
An internal undervoltage lockout circuit monitors V
keeps the PowerPath switching regulator off until V
rises above 4.30V and is about 200mV above the battery
voltage. Hysteresis on the UVLO turns off the regulator if
V
this happens, system power at V
the battery via the ideal diode.
BUS
BUS
OUT
Undervoltage Lockout (UVLO)
drops below 4.00V or to within 50mV of BAT. When
IDEAL
DIODE
exceeds the suspend current limit, the additional
OV
15mV
–
+
+
–
GATE
V
OUT
BAT
SW
22
20
18
19
3566 F03
OUT
.
OUT
+
will be drawn from
OUT
SINGLE CELL
Li-Ion
OPTIONAL
EXTERNAL
IDEAL DIODE
PMOS
, and therefore
SYSTEM LOAD
3.5V TO
(BAT + 0.3V)
OUT
BUS
falls
3566fb
and
BUS