Linear Technology LTC 3115-1 Datasheet

FEATURES
Wide V Range: 2.7V to 40V
n
IN
Wide V Range: 2.7V to 40V
n OUT
1A Output Current for V
n
2A Output Current in Step-Down Operation
n
for V ≥ 6V
IN
Programmable Frequency: 100kHz to 2MHz
n
Synchronizable Up to 2MHz with an External Clock
n
Up to 95% Efficiency
n
30µA No-Load Quiescent Current in Burst Mode
n
Operation
Ultralow Noise Buck-Boost PWM
n
Internal Soft-Start
n
3µA Supply Current in Shutdown
n
Programmable Input Undervoltage Lockout
n
Small 4mm × 5mm × 0.75mm DFN Package
n
Thermally Enhanced 20-Lead TSSOP Package
n
AEC-Q100 Qualified for Automotive Applications
n
APPLICATIONS
24V/28V Industrial Applications
n
Automotive Power Systems
n
Telecom, Servers and Networking Equipment
n
FireWire Regulator
n
Multiple Power Source Supplies
n
TYPICAL APPLICATION
0.1µF
BST1 SW1
2.7V TO
PV
IN
40V
4.7µF
V
IN
BURST PWM PWM/SYNC
OFF ON RUN
RT
GND
47.5k
Document Feedback
≥ 3.6V, V = 5V
IN OUT
®
10µH
0.1µF
SW2 BST2
PV
OUT
47µF
LTC3115-1
3300pF
60.4k
VC
FB
PV
CC
V
CC
PGND
4.7µF
For more information
40V, 2A Synchronous
Buck-Boost DC/DC
DESCRIPTION
The LTC 3115-1 is a high voltage monolithic synchronous
®
buck-boost DC/DC converter. Its wide 2.7V to 40V input
and output voltage ranges make it well suited to a wide
variety of automotive and industrial applications. A propri-
etary low noise switching algorithm optimizes efficiency
with input voltages that are above, below or even equal
to the output voltage and ensures seamless transitions
between operational modes.
Programmable frequency PWM mode operation pro-
vides low noise, high efficiency operation and the ability
to synchronize switching to an external clock. Switching
frequencies up to 2MHz are supported to allow use of
small value inductors for miniaturization of the appli-
cation circuit. Pin selectable Burst Mode operation
reduces standby current and improves light load effi-
ciency which, combined with a 3µA shutdown current,
make the LTC3115-1 ideally suited for battery-powered
applications. Additional features include output discon-
nect in shutdown, short-circuit protection and inter-
nal soft-start. The LTC3115-1 is available in thermally
enhanced 16-lead 4mm × 5mm × 0.75mm DFN and
20-lead TSSOP packages.
All registered trademarks and trademarks are the property of their respective owners. Protected
by U.S. Patents including 6404251, 6166527 and others pending.
5V
1A V > 3.6V
IN
2A V ≥ 6V
IN
1M 33pF
15k
249k
(OPTIONAL)
3115 TA01a
www.analog.com
LTC3115-1
Converter
Efficiency vs V
IN
95
I
LOAD
90
I = 1A
LOAD
85
80
75
70
2 10
INPUT VOLTAGE (V)
= 0.5A
V = 5V
OUT
40
31151 TA01b
Rev. C
1