Quick Start Procedure - Linear Technology DC2490A Demo Manual

DEMO MANUAL DC2490A

Quick start proceDure

Demonstration circuit 2490A is easy to set up to evalu-
ate the performance of the LT8303. Refer to Figure 1 for
proper measurement equipment setup and follow the
procedure below:
1. With power off, connect the input power supply to the
board through V
nect the load to the terminals V
on the board.
2. Turn on the power at the input. Increase V
NOTE: Make sure that the input voltage is always within
spec. To operate the board with higher input/output
voltage, input capacitor, output capacitor and output
diode with higher voltage ratings are needed.
2
Arrow.com. Arrow.com.
Downloaded from Downloaded from
(E1) and GND (E2) terminals. Con-
IN
+
(E3) and V
OUT
slowly to 36V.
IN
3. Check for the proper output voltages. The output should
be regulated at 5V (±5%).
NOTE: The LT8303 requires very small minimum load
to maintain good output voltage regulation. A Zener
diode is placed on the output to clamp the voltage to
5.6V. This Zener can be replaced with a 2000Ω resistor
–
(E4) at the trade-off of lower efficiency.
OUT
4. Once the proper output voltage is established, adjust
the input voltage and load current within the operating
range and observe the output voltage regulation, ripple
voltage, efficiency and other parameters.
NOTE: When measuring the input or output voltage
ripples, care must be taken to avoid a long ground
lead on the oscilloscope probe. Measure the input or
output voltage ripple by touching the probe tip directly
across the V
–
V (E4) terminals. See Figure 2 for proper scope
OUT
probe technique.
(E1) and GND (E2), or V
IN
+
(E3) and
OUT
dc2490af