Linear Technology DC1007C Manual

DESCRIPTION
Demonstration Circuit 1007 is a high efficiency USB power
manager with PowerPath™ control and Li-Ion/Polymer
battery charger featuring the
chronous switching input regulator, a full featured battery
charger and an ideal diode. Designed specifically for USB
applications, the LTC4088's switching regulator automati-
cally limits its input current to either 100mA, 500mA or
1A for wall-powered applications via logic control. There
are also 2.5mA and 500µA suspend modes to prevent the
battery from running down when the product is connected
to a suspended USB bus.
The switching input stage provides power to VOUT where
power sharing between the application circuit and the
battery charger is managed. Unlike linear PowerPath
controllers, the LTC4088's switching input stage can use
nearly all of the 0.5W or 2.5W available from the USB port
with minimal power dissipation. This feature allows the
LTC4088 to provide more power to the application and
PERFORMANCE SUMMARY
SYMBOL PARAMETER
V Input Voltage Range
BUS
V
OUT
V 3.3V
LDO3V3
V Output Float Voltage (Constant Voltage Mode)
BAT
I Output Charge Current (Constant Current Mode)
BAT
LTC 4088. It includes a syn-
®
Specifications are at T
CONDITIONS
Mode and Load Dependent
Load and VOUT Dependent
R
PROG
DEMO MANUAL DC1007C
High Efficiency Battery
Charger/Power Manager
battery and eases thermal issues in space constrained
applications.
An ideal diode ensures that the system power is available
from the battery when the input current limit is reached or
if the USB or wall supply is removed. The optional external
P-channel MOSFET supplements the internal ideal diode
by reducing R and increasing efficiency.
ON
A CHRG LED indicates four possible states of the battery
charger. Charging is indicated when the LED is steady-ON.
Not charging is indicated by a steady-OFF . A NTC fault is
indicated by a slow blinking rate (1.5Hz) and a bad battery
is indicated by a fast blinking rate (6.1Hz).
The LTC4088 is available in the low profile 14-Lead
4mm × 3mm × 0.75mm DFN surface mount package.
Design files for this circuit board are available at
http://www.linear.com/demo/DC1007C
L, LT, LTC, LTM, Linear Technology, the Linear logo and PowerPath are registered trademarks
of Linear Technology Corporation. All other trademarks are the property of their respective
owners.
= 25°C
A
Equals 2kΩ
LTC4088
MIN TYP MAX UNITS
4.35 5.5
3.5 4.7
3.3
4.2
0.5
dc1007cf
V
V
V
V
A
1