6
dc1717afa
DEMO MANUAL DC1717A
Quick start proceDure
Refer to the Figure 3 for proper measurement equipment
setup and follow the procedure below:
Initially, the LTC4417 should be disabled by:
•
placing the jumper
JP2
(EN) header in the OFF position,
and
•
placing the jumper
JP3
(
SHDN
) header in the OFF
position
Connecting the auxiliary power source (6V to 24V) to
the DC1717A (AVI and GND turrets) lights the green LED
(LDO-D12) indicating the presence of aux5V supply
for powering logic.
With power off, connect three power supplies with output
voltages of 12V, 5V, and 8V to corresponding DC1717A
turrets or banana jacks V1(+12V), V2(+5V), V3(+8V),
and GND.
Connect 6Ω load resistor (30W) to the DC1717A output
turret or banana jack (VOUT). Do not use an electronic
load in constant current mode.
Turn on three power supplies. No additional LEDs should
light.
Change the jumper
JP3
(
SHDN
) header position from
OFF to ON. Three LEDs (
VALID1
,
VALID2
, and
VALID3
)
validating the input rail voltages should light.
Placing the jumper
JP2
(EN) in the ON position turns on
the LTC4417 powering the load with 12V (2.0A). In an
initial power up the LTC4417 uses a fixed slew rate for the
output voltage, which should be not larger than 5V/ms.
The prioritizing function is demonstrated by simply turning
off one or two of the V1, V2 and V3 supplies. The output
will be powered from the remaining supply of the high-
est priority. V1, V2 and V3 may be adjusted up and down
beyond ±20% to invalidate a given input.
6Ω
RESISTIVE
LOAD
12V
POWER
SUPPLY
5V
POWER
SUPPLY
8V
POWER
SUPPLY
Figure 3
