KSZ8873MML Evaluation Board User’s Guide
Micrel, Inc.
January 11, 2011
Confidential
Rev. 1.1
5/11
user can supply power from any 110-240 Volt AC wall or bench socket, and the power also can
be provided by USB port when close pin 2-3 of the JP44 jumper.
Figure 1: KSZ8873MML Evaluation Board Block Diagram
The KSZ8873MML evaluation board is easy to use. There are programmable LED indicators for
link and activity on the PHY port and a power LED. A manual reset button allows the user to
reset the board without removing the power plug. The 5V power on the board can be supplied by
a standard 5VDC power supply or by the USB cable (close pin 2-3 of JP44 jumper) which is used
to access the registers in SPI mode. The JP44 is used to select the power supply. A standard
5VDC power supply is included so that the user can supply power from any 110 Volt AC wall or
bench socket. Before to start to use the evaluation board, make sure the power connectors
JP103, JP104, JP105 and JP107 are connected, and close pin 1-2 of J14.
4.1 Strap In Mode
Strap in configuration mode is the quickest and easiest way to get started. In this mode, the
KSZ8873MML acts as a standalone 3-port switch. Simply set the board’s configuration jumpers
to the desired settings and apply power to the board. The configuration can be changed while
power is applied to the board by changing the jumper settings and pressing the convenient
manual reset button for the new settings to take effect. Note that even if no external strap in
values are set, internal pull up and pull down resistors will set the KSZ8873MML default
configuration. Section 4.1.1 covers each jumper on the board and describes its function. To
