Datasheet
MAX5969B Evaluation Kit
Evaluates: MAX5969A/MAX5969B
_______________________________________________________________________________________ 5
Under severe fault or failure conditions, this EV kit can
dissipate large amounts of power, which could result in
the mechanical ejection of a component or of component
debris at high velocity. Operate this EV kit with care to
avoid possible personal injury.
PD Classification Signature
By default, the EV kit is set for a Class 4 (12.95W to
25.5W) PD classification by resistor R2. To change the
PD classification, replace surface-mount resistor R2.
Table 1 lists the PD classification options.
Wall Adapter Power Source (WAD, RTN)
The EV kit can also accept power from a wall adapter
power source. Use the WAD PCB pad for connecting
the more positive terminal and the RTN PCB pad for con-
necting the more negative terminal to the wall adapter
power source. The wall adapter power-source operating-
voltage range must be within +30V to +57V for the EV kit.
When the wall adapter power source is above +10V, it
takes precedence over the PSE source. Once the wall
adapter power source is detected, the IC’s internal
isolation switch disconnects VSS from RTN. The wall
adapter power is supplied to VDD (through diode D2)
and RTN. Once it takes over, the classification process
is disabled.
When the wall adapter power source is below +7V, the
PSE provides power through the IC’s RTN. Diode D2
prevents the PSE from back-driving the wall adapter
power source when it is below +7V.
Ethernet Data Signal Interfacing
The EV kit features a modular RJ45 jack (J3) to inter-
face with the Ethernet data signals. J3 is provided for
interfacing the EV kit with the Ethernet data signals only.
Refer to the RJ45 magnetic jack data sheet on the Bel
Fuse website prior to interfacing the EV kit’s J3 modular
RJ45 jack with the Ethernet data signals.
Evaluating the MAX5969A
The EV kit can also evaluate the MAX5969A. Remove the
MAX5969B IC (U1) and replace it with the MAX5969A.
The MAX5969A is pin compatible with the MAX5969B.
The MAX5969A has a lower UVLO of -35.4V com-
pared to the MAX5969B’s UVLO of -38.6V. Refer to
the MAX5969A/MAX5969B IC data sheet for additional
information.
Table 1. PD Classification Signature
Selection
CLASS
MAXIMUM POWER
USED BY PD (W)
RESISTOR
R2 (I)
0 0.44 to 12.95 619
1 0.44 to 3.84 118
2 3.84 to 6.49 66.5
3 6.49 to 12.95 43.2
4 12.95 to 25.5 30.9
5 > 25.5 21.5