MAX5971AEVKIT Maxim Integrated, MAX5971AEVKIT Datasheet - Page 5

• Manufacturer Part Number: MAX5971AEVKIT
• Description: Power Management IC Development Tools
• Manufacturer: Maxim Integrated
• Series: MAX5971r

*Default position.
Table 5. PSE Circuit Resistor Changes for Midspan/End-Point Configuration
*Default position.
Table 6. Jumper JU5 Legacy Modes
*Default position.
The EV kit features a 2-pin jumper (JU5) to set the IC’s ini-
tial startup legacy operational mode. In legacy mode, PD
signature capacitances up to 47FF (typ) are accepted.
Table 6 lists the jumper options. Refer to the MAX5971A
IC data sheet for more information.
The EV kit features a 2-pin jumper (JU6) to disable the
IC’s internal triangular-wave oscillator at the OSC pin.
The oscillator is used for AC-disconnect monitoring of
the PD and is disabled for DC-disconnect operation. For
AC-disconnect operation, the internal oscillator is used
along with RCD components R3, C4, D3, and blocking-
diode D4. Perform a power-on or reset the IC using push-
button switch SW1 to affect the changes.
For DC-disconnect operation, shut down the internal
oscillator by installing a shunt on jumper JU6. Then
remove resistor R3 and install a 0I 0402 surface-
mount resistor on R9 to bypass blocking-diode D4.
Diode D3 remains installed. Refer to the AC Disconnect
Monitoring and DC Disconnect Monitoring sections in
the MAX5971A IC data sheet for additional information.
Table 7 lists the jumper options for the oscillator and AC/
DC configurations. Refer to the MAX5971A IC data sheet
for more information.
Table 4. Jumper JU4 Functions (MIDSPAN)
SHUNT POSITION
Legacy High-Capacitance-Detection Operation
CONFIGURATION
Not installed*
SHUNT POSITION
Installed
AC-Disconnect Monitoring Oscillator and
Midspan*
End point
Not installed
Installed*
_________________________________________________________________ Maxim Integrated Products 5
AC-/DC-Disconnect Operation
Connected to VEE through resistor R13
Not installed
Connected to VEE through resistor R15
Installed
Internally pulled high
R5
MIDSPAN PIN
Internally pulled high
LEGACY PIN
MAX5971A Evaluation Kit
Not installed
The EV kit features pushbutton switch SW1 to reset the
IC or set the IC’s initial startup operational mode. Table 8
lists the switch options.
For operation greater than 35W, the RJ45 jack (J2) cannot
be used. The EV kit features PCB pads and banana jacks
to interface directly with the output port power. Use the
GND and RTN PCB pads or jacks to access the output
port’s power without an Ethernet connection.
The EV kit features test points to facilitate voltage measur-
ing at each port’s respective LED, ILIM1, ILIM2, PWMEN,
MIDSPAN, LEGACY, and EN pins on the IC. For the VEE
connection, test points TP11 and TP13 can be used.
The output port current can be measured by replacing
any output port single resistor—R5 or R6 when operating
in midspan and R7 or R8 when operating in end point.
Replace the respective resistor with a 1I Q1% 1206
surface-mount resistor.
Installed
R6
Evaluates: MAX5971A
RESISTOR
Operation Without an Ethernet Connection
Not installed
Enabled, detect high capacitance
Installed
Reset and Automatic Operation
R7
PoE CONFIGURATION
IC Pins Signal Measurements
LEGACY MODE
Endpoint
Midspan
Disabled
Not installed
Installed
R8