QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 627
BOOST CONVERTER
1
LT3461 / LT3461A
DESCRIPTION
Demonstration circuit 627 features the LT3461 /
LT3461A in a 12.0V output boost converter which
operates from an input voltage of 3V to 6V. The
maximum output current is 70mA when powered
from a 5.0V input and 40mA when powered from a
3.3V input. A soft-start option is provided by the
SHDN pin and can be configured with an on-board RC
filter.
The internal schottky of the LT3461 / LT3461A re-
duces part count and the high switching frequency
allows the use of a small SMT inductor and output
capacitors. The small size of the circuit makes it ideal
for space-sensitive applications.
The DC627A comes in two versions. The “-A” version
uses the LT3461 and the “-B” version uses the
LT3461A.
Design files for this circuit board are available. Call
the LTC factory.
LT is a trademark of Linear Technology Corporation
Table 1.
Performance Summary (T
A
= 25°C)
PARAMETER CONDITION
DC627A-A
VALUE
DC627A-B
VALUE
LT Part
LT3461ES6
LT3461AES6
Minimum Input Voltage
3V
3V
Maximum Input Voltage
6V
6V
Output Voltage V
OUT
V
IN
= 3V to 6V
12V ±4%
12V ±4%
Maximum Output Current
V
IN
= 3.3V
V
IN
= 5.0V
40mA
70mA
40mA
70mA
Typical Efficiency
V
IN
= 3.3V, I
OUT
= 40mA
V
IN
= 5.0V, I
OUT
= 70mA
79%
83%
76%
81%
Typical Output Voltage Ripple
(20MHz BW)
V
IN
= 3.3V, I
OUT
= 40mA
V
IN
= 5.0V, I
OUT
= 70mA
20mV
P–P
28mV
P–P
9mV
P–P
12mV
P–P
Nominal Switching Frequency
1.3MHz
3.0MHz
QUICK START PROCEDURE
Demonstration circuit 627 is easy to set up to evalu-
ate the performance of the LT3461 or LT3461A. Refer
to Figure 1 for the proper measurement equipment
setup and follow the procedure below:
1.
Place jumper JP1 in the “ON” position if not al-
ready done.
2.
With power off, connect the input power supply.
3.
Turn on the input power source and set it to 3.3V.
The output should be 12.0V ±4% at no load.
4.
Connect the load from VOUT to GND and set to
40mA. The output should still be 12.0V ±4%.