LT8580_15 Datasheet, PDF (1/32 Pages) Linear Technology – Boost/SEPIC/Inverting DC/DC Converter with 1A, 65V Switch, Soft-Start and Synchronization

LT8580
Boost/SEPIC/Inverting
DC/DC Converter with 1A, 65V
Switch, Soft-Start and Synchronization
Features
n _{1A, 65V Power Switch}
n _{Adjustable Switching Frequency}
n _{Single Feedback Resistor Sets VOUT}
n _{Synchronizable to External Clock}
n _{High Gain SHDN Pin Accepts Slowly Varying}
Input Signals
n _{Wide Input Voltage Range: 2.55V to 40V}
n _{Low VCESAT Switch: 400mV at 0.75A (Typical)}
n _{Integrated Soft-Start Function}
n _{Easily Configurable as a Boost, SEPIC, or Inverting}
Converter
n _{User Configurable Undervoltage Lockout (UVLO)}
n _{Pin Compatible with LT3580}
n _{Tiny Thermally Enhanced 8-Lead 3mm × 3mm DFN}
and 8-Lead MSOP Packages
Applications
n _{VFD Bias Supplies}
n _{TFT-LCD Bias Supplies}
n _{GPS Receivers}
n _{DSL Modems}
n _{Local Power Supply}
Description
The LT^®8580 is a PWM DC/DC converter containing an
internal 1A, 65V switch. The LT8580 can be configured
as either a boost, SEPIC or inverting converter.
The LT8580 has an adjustable oscillator, set by a resistor
from the RT pin to ground. Additionally, the LT8580 can be
synchronized to an external clock. The switching frequency
of the part may be free running or synchronized, and can
be set between 200kHz and 1.5MHz.
The LT8580 also features innovative SHDN pin circuitry
that allows for slowly varying input signals and an adjust-
able undervoltage lockout function.
Additional features such as frequency foldback and
soft-start are integrated. The LT8580 is available in tiny
thermally enhanced 3mm × 3mm 8-lead DFN and 8-lead
MSOP packages.
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
ThinSOT is a trademark of Linear Technology Corporation. All other trademarks are the
property of their respective owners. Protected by U.S. Patents, including 7579816.
Typical Application
1.5MHz, 5V to 12V Boost Converter
15µH
V_IN
5V
10k
V_OUT
12V
200mA
2.2µF
V_IN
SW
SHDN
FBX
LT8580
SYNC
VC
RT GND SS
130k
6.04k
56.2k
0.22µF
3.3nF
4.7µF
47pF
8580 TA01a
100
90
80
70
60
50
40
30
20
0
Efficiency and Power Loss
480
420
360
300
240
180
120
EFFICIENCY 60
POWER LOSS
0
50
100
150
200
LOAD CURRENT (mA)
8580 TA01b
For more information www.linear.com/LT8580
8580f
1