Linear Technology Demo Circuit 1402A, Quick Start Manual

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LTC3577 AND LTC3577-1
1
DESCRIPTION
Demo Circuit 1402A
QUICK START GUIDE
LTC3577 and LTC3577-1
Highly Integrated 6-Channel
Portable PMIC
WARNING!
Do not look directly at operating LED.
This circuit produces light that can damage eyes.
Demo Circuit 1402 is a Highly Integrated 6-Channel
Portable PMIC with a push button controller, two LDOs,
three buck converters, a Li-Ion battery charger, a Power-
Path controller, and high voltage buck controller interface
featuring the LTC3577 and LTC3577-1.
The LTC3577 is a PowerPath™ manager with automatic
load prioritization, battery charger, Bat-Track™ control-
ler, push button controlled power up sequence and reset,
and a 10 LED string controller with gradation and PWM
control. The three buck regulators and the LED Boost
controller have adjustable slew rates for EMI reduction.
The LTC3577 has a high temperature battery voltage re-
duction feature that reduces the battery voltage under
high temperature conditions to improve safety and reli-
ability.
The high voltage (HV) buck interface is designed to con-
nect to and control an external HV buck regulator demo
board via the Bat-Track control circuitry. Some of these
demo boards are the DC1394A, DC1395A, and DC1325A,
featuring the LT3480, LT3505, and the LT3563 HV bucks
respectively.
Refer to the LTC3577 datasheet for more details on the
electrical and timing specifications.
Design files for this circuit board are available. Call
the LTC factory.
L
, LTC, LTM, LT 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.
PERFORMANCE SUMMARY
Specifications are at T
A
= 25°C
PARAMETER CONDITIONS MIN TYP MAX UNITS
Input Supply Range (V
BUS
) NOTE: The input current limit is reduced when VBUS falls
below 4.45V (TYP). 4.35 5.5 V
Absolute Wall Input Threshold (V
W
) V
WALL
Rising
V
WALL
Falling 3.1
4.3
3.2 4.45 V
V
DV
CC
Operating Voltage 1.6 5.5 V
DV
CC
UVLO (V
DVCC,UVLO)
1 V
V
BAT
Regulated Output Voltage (V
FLOAT
) LTC3577
LTC3577-1
4.179
4.079 4.200
4.100 4.221
4.121 V
V
Constant Current Mode Charge Current (I
CHRG
) R
PROG
= 2K
Ω
, Input current limit = 1A 465 500 535 mA
V
OUT
UVLO V
OUT
Falling
V
OUT
Rising
2.5 2.7
2.8 2.9
V
V
V
OUT1
0 to 500mA 3.3 V
V
OUT2
0 to 500mA 1.8 V
V
OUT3
0 to 800mA 1.2 V
LDO1 0 to 150mA 1.5 V
LDO2 0 to 150mA 2.5 V
Full-Scale LED Current 20 mA