3
dc1145bf
DEMO MANUAL DC1145B
Figure 1. DC1145B Test Setup
Demonstration circuit 1145B is easy to set up to evaluate
the performance of the LTC4267. For proper equipment
setup, refer to Figure 1 and follow the procedure below:
1. Apply an initial load of 100mA at V
OUT
.
2. Connect a PoE compliant Power Sourcing Equipment
(PSE) to RJ45 connector J1.
3. The PSE will detect and power up the PD. Verify output
voltage measures 12V.
4. If the PSE has status readout, verify the proper PD
power class 3 was detected.
5. In place of a PSE, the DC1145 board can be powered
by an alternate input power supply. Connect 48V
through the PoE+ and PoE– terminals. Only one set of
connections is necessary. Do not connect more than
one power source.
6. Increase the load at V
OUT
up to 0.9A. Observe the
output regulation, ripple voltage, efficiency and other
parameters
7. Measure
PWRGD
and SIGDISA relative to POE–. Verify
PWRGD
is logic low and SIGDISA is logic low.
8. Connect a 12V auxiliary supply and verify V
OUT
equals
the new supply.
9. Measure
PWRGD
and SIGDISA relative to POE–. Verify
PWRGD
is logic high and SIGDISA is logic high.
10. Remove the 12V auxiliary supply and verify the PSE
power returns.
PSE
RJ45
RJ45
CAT5
CABLE
LOAD
V
A
+
+
+
–
–
–
QUICK START PROCEDURE
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