Quick Start Guide for Demo Board DC414
Demonstration circuit DC414 is a step-up (Boost) DC-DC converter featuring the LTC1871
controller. The circuit is capable of providing an output voltage of 5V at 7A (10A peak) from an
input supply of 3.3V. External frequency synchronization is provided, as are two modes of
operation at light load conditions: Burst mode operation to reduce switching losses and
maintain high operating efficiency, and continuous mode to provide constant operating frequency
with low quiescent current. The LTC1871 is a No R
SENSE
current mode step-up controller. It
eliminates the need for a current sense resistor and maximizes the efficiency of the demo circuit
—up to 95%. The LTC1871 can operate up to a frequency of 1MHz, allowing for the use of small
inductors and capacitors. The low shutdown quiescent current of 10µA makes the LTC1871
ideally suited for battery-operated systems. Applications include telecom power supplies, cellular
phones, PDAs and portable electronic equipment.
Quick Start Procedure
Refer to Figure 1 for proper measurement equipment setup and follow the procedure below:
1.
Connect input power to the V
IN
and GND terminals. The input voltage can be between 3V and
5V.
2.
Connect a load between the V
OUT
and GND terminals.
3.
Connect the MODE SNYC terminal to INTV
CC
by setting the jumper to the upper position
(CONT.) to force continuous operation at low load, or connect the MODE SYNC terminal to
ground by setting the jumper to the lower position (BURST) to enable Burst Mode operation
at low load.
4.
To shut down the circuit, connect the RUN terminal to ground.
+
–
+
–
+
–
+
–
LOAD
+
–
+
–
CONT.
BURST
VIN
GND
VOUT
GND
MODE
SYNC
RUN
LTC1871EMS
High Efficiency Boost Converter Logic Supply
Demo Circuit DC414A
Figure 1. Proper Measurement Equipment Setup
DC414 Quick Start Guide Page 1 of 1
