Datasheet
MAX5980 Evaluation Kit
Evaluates: MAX5980
13Maxim Integrated
Mode Selection (Midspan or Signal)
The EV kit features a 3-pin jumper (JU5) to set the IC in
midspan or signal mode. Table 2 lists the jumper options
for the two modes used to detect a valid PD connected
to the PSE’s respective Ethernet output port. Refer to the
MAX5980 IC data sheet for more information on these
modes.
Operational Modes
(Automatic and Shutdown)
The EV kit features a 3-pin jumper (JU6) to set the IC’s
initial startup operational mode. After startup, data sent to
the Operating Mode register (R12h) reconfigures the oper-
ational mode of the IC. Table 3 lists the jumper options.
Class 5 Enable (EN_CL5)
The EV kit features a 2-pin jumper (JU8) to enable/disable
the IC’s hardware Class 5 classification settings. Refer to
the MAX5980 IC data sheet for Class 5 register settings
with respect to this pin. Table 4 lists the jumper options.
Stand-Alone Microcontroller Interface
(Isolated /Nonisolated)
The EV kit features PCB pads and a jumper to interface
directly with a microcontroller. The 10-pin (2 x 5) jumper
(JU9) has shorting connections on the bottom layer that
must be cut open to disable the optocoupler interface for
nonisolated evaluation. The JU9 jumper shorting connec-
tions must be in place for evaluating an isolated stand-
alone microcontroller interface or the on-board USB
interface circuit. For evaluating an isolated stand-alone
microcontroller interface, cut open the PC trace shorts
on jumpers JU10, JU39, and JU40 to isolate the on-board
USB interface circuit. Table 5 lists the selectable jumper
options.
PORT OUT_, GATE_ Pins Signal Measurements
The EV kit features jumpers to facilitate current and
voltage measuring at each port’s respective OUT_ and
GATE_ pins on the IC. Several 2-pin and 4-pin jumpers
are used to obtain the desired measurement for each
port. Jumper JU11 is provided for port 1, jumper JU12
is provided for port 2, jumper JU13 is provided for port
3, and jumper JU14 is provided for port 4. The jumper
pins are shorted by a PCB trace on the top layer of the
EV kit by default for normal operation. The shorts can be
cut open for measurements. See Figure 5a for a specific
port’s jumper.
SENSE_ Pins Signal Measurements
The EV kit features jumpers to facilitate current and volt-
age measuring at each port’s respective SENSE_ pins
on the IC. Several 2-pin jumpers are used to obtain the
desired measurement for each port. Jumper JU23 is
provided for port 1, jumper JU24 is provided for port 2,
jumper JU25 is provided for port 3, and jumper JU26
is provided for port 4. The jumper pins are shorted by
a PCB trace on the top layer of the EV kit by default for
normal operation. The shorts can be cut open for mea-
surements. See Figure 5a for a specific port’s jumper.
-48V/-54V Port Power Interface, Voltage Measure-
ment, or Port1/Port3 60W 2 x 2 Pair Operation
The EV kit includes jumpers JU27–JU30 to disconnect each
port’s -48V/-54V power independently for connection to an
external network interface circuit, or to increase the avail-
able power at port 1 and/or port 3 up to 60W. Additionally,
the respective jumper pins can also be utilized to measure
the voltage or current for the respective port. Table 6 lists
the specific jumper for each port. Each jumper has a short-
ed PCB trace on the bottom layer of the PCB.
Table 2. Jumper JU5 Functions
Table 3. Initial Startup Operational Mode (JU6)
Table 4. Class 5 Enable (JU8)
SHUNT POSITION MIDSPAN PIN MODE
1-2 Connected to VDIG through resistor R14 Midspan
2-3 Connected to DGND through resistor R14 Signal
SHUNT POSITION AUTO PIN
OPERATING MODE REGISTER
(R12h) STATUS BITS
OPERATION MODE
1-2 Connected to VDIG through resistor R15 0x00 Automatic
2-3 Connected to DGND through resistor R15 0xFF Shutdown
SHUNT POSITION EN_CL5 PIN CLASS 5
Installed Connected to VDIG Enabled
Not installed Connected to DGND internally Disabled