QUICK START GUIDE FOR DEMONSTRATION CIRCUIT
1053A-A through 1053A-D
SYNCHRONOUS BOOST DC/DC CONVERTER
2
Table 2. Demonstration Circuit Board Information
1053A-A
LTC3526EDC
LCHW
1MHz
Burst
1053A-B
LTC3526BEDC
LCNN
1MHz
No Burst
1053A-C
LTC3526-2EDC
LCNM
2MHz
Burst
1053A-D
LTC3526B-2EDC LCNP
2MHz
No Burst
Board
Number
LTC Part
Part
Marking
Frequency
Mode
QUICK START PROCEDURE
There is one demonstration circuit board for
all four LTC3526 versions. The boards are
identified by the handwritten information on
the top of the pc board.
The boost converter can be evaluated using
the setup shown in Figure 1. Select one of the
three output voltages using jumpers JP1
through JP3. (With no jumpers installed, the
output voltage is 5V.) Set jumper JP4 in the
ON position and connect voltmeters and am-
meters as shown on the test setup. Connect a
power supply to the V
IN
and GND terminals
and a suitable load resistor between VOUT
and GND.
With a light load (1k resistor) at the output,
begin increasing the input power supply volt-
age. At approximately 850mV, the output will
rise to the selected regulated voltage. In-
crease the input voltage to approximately
1.5V and increase the load current.
Note the excellent load regulation when going
from a light load current to a heavier load, but
it is important to monitor the input voltage di-
rectly at the input terminals of the circuit
board. At very low input voltages, voltage
drops in the power supply wire, connections
and Ammeter will result in the input voltage at
the input terminals dropping below the mini-
mum voltage required for operation.
Additional pc board pads are provided for an
optional input bypass capacitor (C1). It may
be necessary when using long wires between
the power supply and circuit board, or for add-
ing a tantalum capacitor to minimize input
voltage transients that may occur when the
input is hot-switched. Also, pads on the board
backside are provided for adding a small
Schottky diode (D1) which can increase the
efficiency slightly under some conditions. But
adding a diode defeats the output disconnect
and short circuit protection features.
When verifying output ripple, it is important to
use the scope probe connection as shown in
Figure 3.
In Burst mode with light load current, the out-
put ripple voltage is higher than in non-burst
mode.
See LTC3526 Data Sheet for additional information
V
OUT
GND
Figure 3. Scope Probe Placement for
Measuring Output Ripple Voltage
