LT8580
1
8580fa
For more information www.linear.com/LT8580
Typical applicaTion
FeaTures
applicaTions
DescripTion
Boost/SEPIC/Inverting
DC/DC Converter with 1A, 65V
Switch, Soft-Start and Synchronization
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.
1.5MHz, 5V to 12V Boost Converter
n
1A, 65V Power Switch
n
Adjustable Switching Frequency
n
Single Feedback Resistor Sets V
OUT
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 V
CESAT
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
n
VFD Bias Supplies
n
TFT-LCD Bias Supplies
n
GPS Receivers
n
DSL Modems
n
Local Power Supply
Efficiency and Power Loss
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.
LOAD CURRENT (mA)
0
20
EFFICIENCY (%)
POWER LOSS (mW)
40
50
60
100
100
8580 TA01b
30
50
150
200
70
80
90
0
180
300
480
240
60
120
360
420
EFFICIENCY
POWER LOSS
4.7µF
V
OUT
12V
200mA
15µH
130k
V
IN
5V
V
IN
SW
8580 TA01a
LT8580
10k
6.04k
56.2k
SHDN
GND
FBX
VCSYNC
SSRT
3.3nF
47pF
0.22µF
2.2µF