This section describes the connectors and the test
points on the EVM and how to properly connect, set up, and use the LM5168FEVM EVM.
See Figure 3-1 for location of connectors and jumpers.
VOUTOutput voltage of the converterVOUT screw terminal connector. Apply load to this connector (+ and –). The VOUT test point is
used to monitor output voltage.
VOUT2Secondary output voltage of the converterVOUT2 screw terminal connector. One side of this output is connected to the primary ground (GND)
through a tie resistor, Rtie (R12). This resistor can be removed
for a true floating voltage source. Apply load to this connector (+ and –).
GNDGround of the converterGND and GNDS test points. Used as ground test points for the EVM.
VINInput voltage to the converterVIN screw terminal connector. Apply input voltage to this connector (+ and –). The VIN test
point is used to monitor input voltage.
VINEMIInput voltage to input filter of the converterIf it is desired to use the built-in EMI filter on the EVM, then connect the input supply to the
VINEMI screw terminal connector (+ and –).
Input FilterEMI mitigationAn input EMI filter is provided on the EVM. Note L2 and C18 are not populated and must be
installed for the EMI filter to operate. Also, note that the maximum input
voltage to the filter is 100 VDC.
EN/UVLO JumperSet EN/UVLO pin optionsUse this jumper to enable/disable the EVM. The resistors connected to this pin set the input
UVLO thresholds. Input UVLO thresholds are set to approximately 6 V and 5.6
V. These levels can be changed by changing the values of R5 and R7. For
external control of the device, these resistors should be removed and the
control signal applied to the center pin of the header. Note that for
accurate shutdown current measurement, these resistors must also be removed
and the EN input (center pin) grounded.
- Jumper open (default
setup): Device starts up and shuts down with UVLO.
- Center pin connected
to ON: Device starts up and shuts down without UVLO.
- Center pin connected
to OFF: Device is off.
PGOODThe PGOOD header used as a test point to monitor the power-good indicator. This flag indicates
whether the output voltage has reached its regulation level. PGOOD is an
open-drain output that is tied to VOUT through a 100-kΩ, resistor
R10.