Datasheet

KSZ8721BL/SL
DS00002813A-page 4  2018 Microchip Technology Inc.
1.0 INTRODUCTION
1.1 General Description
Operating with a 2.5V core to meet low-voltage and low-power requirements, the KSZ8721BL and KSZ8721SL are
10BASE-T/100BASE-TX/FX Physical Layer Transceivers that use MII and RMII interfaces to transmit and receive data.
They contain 10BASE-T Physical Medium Attachment (PMA), Physical Medium Dependent (PMD), and Physical
Coding Sub-layer (PCS) functions. The KSZ8721BL/SL also have on-chip 10BASE-T output filtering. This eliminates
the need for external filters and allows a single set of line magnetics to be used to meet requirements for both
100BASE-TX and 10BASE-T.
The KSZ8721BL/SL automatically configure themselves for 100 or 10Mbps and full-duplex or half-duplex operation,
using an on-chip auto-negotiation algorithm. They are the ideal physical layer transceiver for 100BASE-TX/10BASE-T
applications.
FIGURE 1-1: KSZ8721BL/SL FUNCTIONAL DIAGRAM
10/100
Pulse
Shaper
NRZ/NRZI
MLT3 Encoder
Parallel/Serial
Manchester Encoder
4B/5B Encoder
Scrambler
Parallel/Serial
Transmitter
TX+
TX-
Adaptive EQ
Base Line
Wander Correction
MLT3 Decoder
NRZI/NRZ
Clock
Recovery
4B/5B Decoder
Descrambler
Serial/Parallel
Auto
Negotiation
10BASE-T
Receiver
Manchester Decoder
Serial/Parallel
PLL
LED
Driver
MII/RMII
Registers
and
Controller
Interface
RX-
RX+
XI
XO
SPD
FDX
COL
LINK
Power
Down or
Saving
PWRDWN
RXC
TXD3
TXD0
TXD1
TXD2
RXD3
TXEN
TXC
TXER
MDC
MDIO
COL
CRS
RXER
RXD0
RXD1
RXD2
RXDV