LT8710_15 Datasheet, PDF (1/44 Pages) Linear Technology – Synchronous SEPIC/ Inverting/Boost Controller with Output Current Control

LT8710
Features
Synchronous SEPIC/
Inverting/Boost Controller with
Output Current Control
Description
n _{Wide Input Range: 4.5V to 80V}
n _{Rail-to-Rail Output Current Monitor and Control}
n _{Input Voltage Regulation for High Impedance Inputs}
n _{C/10 or Power Good Indication Pin}
n _{MODE Pin for Forced CCM or Pulse-Skipping}
Operation
n _{Switching Frequency Up to 750kHz}
n _{Easily Configurable as a Boost, SEPIC, Inverting or}
Flyback Converter with Single Feedback Pin
n _{Can Be Synchronized to External Clock}
n _{High Gain EN/FBIN Pin Accepts Slowly Varying Input}
Signals
n _{20-Lead TSSOP Package}
Applications
n _{High Power Local Power Supply}
n _{Wide Input Voltage Range SEPIC/Inverting}
n _{Lead Acid Battery Charger}
n _{Automotive Engine Control Unit (ECU) Power}
n _{Solar Panel Power Converter}
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
Protected by U.S. Patents, Including 7579816.
The LT^®8710 is a synchronous PWM DC/DC controller
with a rail-to-rail output current monitor and control. The
LT8710 is ideal for many types of power supply topologies
and can be easily configured for boost, SEPIC, inverting,
or flyback configurations.
The LT8710’s rail-to-rail output current monitor and control
allows the part to be configured in current limited applica-
tions such as battery charging. The FLAG pin can be used
as a power good indication or C/10 indication allowing for
accurate bulk and float battery voltages.
The LT8710’s switching frequency range can be set be-
tween 100kHz and 750kHz using an external resistor or
synchronized to an external clock.
The LT8710 also features innovative EN/FBIN pin cir-
cuitry that allows for slowly varying input signals and
an adjustable undervoltage lockout function. The pin is
also used for input voltage regulation to avoid collapsing
a high impedance input supply. Additional features such
as frequency foldback and soft-start are integrated. The
LT8710 is available in a 20-lead TSSOP package.
Typical Application
300kHz Inverter Generates –5V from a 4.5V to 25V Input
V_IN
4.5V TO 25V
+
120µF
2.2µH
13.3k
10k
10µF
2.2µF
×4
118k
10µF ×2
499Ω
2.2µH
V_OUT
–5V
7A
330µF
1.5m
0.47µF
4m
BG
CSN CSP TG
V_IN
ISN
100µF
×2
EN/FBIN
MODE
LT8710
ISP
BIAS
INTV_EE
INTV_CC ^60.4k
2.2µF
INTV_CC
RT
FBX
FLAG
V_C
SYNC GND
IMON
SS
47nF
220nF
100pF
11.5k
3.3nF
8710 TA01a
For more information www.linear.com/LT8710
Efficiency and Power Loss
100
8
90
7
80
6
70
5
65
4
50
3
40
2
30
V_IN = 5V 1
V_IN = 12V
20
0
0 12 3 4 5 67
LOAD CURRENT (A)
8710 TA01b
8710f
1