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dc1555cfd
DEMO MANUAL DC1555C
Demonstration circuit 1555C is easy to set up to evaluate
the performance of the LTC4365/LTC4365-1. Refer to
Figures 1a and 1b for proper measurement equipment
setup and follow the procedure below.
Note that the circuit on the DC1555C is optimized for 12V
operation. The Si4214 FET limits overvoltage and reverse
voltage to 30V and –30V, respectively. Refer to the LTC4365
data sheet for applications optimized for other voltages.
Reverse Voltage Test (Figure 1b)
1) Set JP1 to EN.
2) Set JP2 and JP3 to CONNECT LED.
3) Connect a power supply across VIN and GND in a
negative configuration (connect positive rail to GND
and negative rail to VIN).
4) Connect voltmeters at the input and output and am-
meter in series with supply.
5) Ramp VIN down to –30V (referenced to GND).
6) Verify that the output voltage is between 0V and –0.5V,
all LEDs are off, and the input current is <1.8mA. (FET
leakage or other board leakage paths can pull VOUT
slightly negative, but it will be clamped by the internal
protection diode.)
7) Ramp supply back to 0V.
Undervoltage/Overvoltage Test (Figure 1a)
8) Reverse the polarity of power supply connection across
VIN to GND (connect positive rail to VIN and negative
rail to GND).
9) Ramp supply up to 30V and verify green VIN LED, red
FAULT
LED, green VOUT LED, and VOUT according to
Table 1 within the various voltage ranges.
10) Ramp supply down from 30V down to 0V and verify
green VIN LED, red
FAULT
LED, green VOUT LED, and
VOUT according to Table 1.
Table 1
VIN
VOUT
VIN LED
VOUT LED
FAULT
LED
0V to 5.77V
= 0V
Off/Dim/On
Off
On
6.56V to 13.51V
= V
IN
On
On
Off
15.47V to 30V
= 0V
On
Off
On
Jumper Test
11) Remove load and set supply to 9V.
12) Move jumpers and verify LEDs according to Table 2.
Table 2
JP1
JP2/JP3
VIN LED
VOUT LED
EN
CONNECT LED
On
On
DIS
CONNECT LED
On
Off
EN
Open
Off
Off
Quick start proceDure
