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Constant Current Configuration #4: (PI3740-00-EVAL2 Board)
High Side Current Sense Using INA193 and LGH
For applications where V
OUT
is below 8V and high side current sense is preferred, this
configuration must be used.
This configuration senses current through R
SENSE
and the output of the
INA193 is fed into the LGH pin through a compensation network. The minimum recommended R
SENSE
is
20m
Ω
. The maximum output voltage in this configuration remains 50V
DC
.
Install jumpers as shown.
Install: J301, JTRK, JISP and JISN to connect IS+ and IS- to ground.
Charging Current:
The INA193 has a gain of 20. The output of the INA193 is divided down by R301
and R302. The LGH voltage is 100mv. Therefore the charge current is approximately
(100mv*8/20)/R
SENSE
, or 40mv/R
SENSE
.
Paralleling Boards
Current Sense Element in Each Board
If more current is required than can be supplied by one board, two boards may be used in parallel.
Jumper the following pins together between boards; SGND, TRK, EAO, EN. Use short, low impedance
jumpers especially on the SGND and EAO pins.
Only One Current Sense Element
If only one board has a current-sense resistor, the LGH pins must also be connected together. Also,
the connection to IMON, on the board which does not have the current-sense resistor, must be
opened. (Remove J200).
Stability
The both evaluation boards are designed to be stable in a wide variety of applications. If instability is
seen in your application, contact Vicor’s application support for assistance.
Figure 6
Jumper Placement for
Constant Current Operation
Configuration #4 (EVAL2)
