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dc1543afa
DEMO MANUAL DC1543A
QUICK START PROCEDURE
Demonstration circuit 1543A is an easy way to evaluate
the performance of the LTM4641. Please refer to Figure
1 for proper measurement equipment setup and follow
the procedure below:
1. Place jumpers in the following positions for a typical
3.3V
OUT
application:
INPUT
OVLO
NON-LATCH INPUT
OVP
INPUT UVLO
OVER-TEMP
BEHAVIOR
OFF
OFF
OFF
NON-LATCH
RUN
MODE
TRACK/SS
V
OUT
Select
F
SET
ON
CCM
SS
3.3V
V
OUT
> 3.0V
2. With power off, connect the input power supply, load
and meters as shown in Figure 1. Preset the load to 0A
and V
IN
supply to be 0V.
3. Turn on the power at the input. Increase V
IN
to 12V
(Do not apply more than the rated maximum voltage
of 38V to the board or the part may be damaged).
The output voltage should be regulated and deliver the
selected output voltage ±1.5%.
4. Vary the input voltage from 4.5V to 38V and adjust
the load current from 0A to 10A. Observe the output
voltage regulation, ripple voltage, efficiency, and other
parameters. Output voltage ripple may be measured at
J6 with a BNC cable and oscilloscope. The probe channel
for V
OUT
should be set at 50Ω termination resistance
to match the BNC cable.
5. (Optional) For optional load transient test, apply an
adjustable pulse signal between IOSTEP_CLK and GND
test points. The pulse amplitude sets the load step cur-
rent amplitude. Keep the pulse width short (<1ms) and
pulse duty cycle low (<5%) to limit the thermal stress
on the load transient circuit. The load step current can
be monitored with a BNC connected to J5 (25mV/A).
6. (Optional) To test the advanced input and load pro-
tections, put the corresponding jumper in the “ON”
position. For DC1543A, the thresholds for different
input and output protections are set as shown below:
INPUT OVLO
36V
NON-LATCH INPUT OVP
32V
INPUT UVLO
8V for Rising Edge
7V for Falling Edge
OVER-TEMP
BEHAVIOR
LATCH
145°C
NON-LATCH
145°C: Cease Regulation
135°C: Resume Regulation
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