dp83223 National Semiconductor Corporation, dp83223 Datasheet - Page 4

• Manufacturer Part Number: dp83223
• Description: Dp83223 Twister High Speed Networking Transceiver Device
• Manufacturer: National Semiconductor Corporation

2.0 Pin Description
DP83223 Pinout Summary
V
GND
RXVcc
RXGND
TXVcc
TXGND
EXTVcc
RXI+/-
PMID+/-
PMRD+/-
TXO+/-
SD+/-
TXREF
ENCSEL
LBEN
CC
Symbol
13,26 (10, 25)
14, 22(11 ,20)
25, 24(23, 22)
20, 21(18, 19)
PLCC(PQFP)
15, 16(12,13)
4, 27(26, 31)
3, 28(27, 30)
2, 1(29, 28)
5, 11(1, 7)
7, 10(3, 6)
9, 8(5,4)
Pin No
23(21)
19(17)
12(9)
6(2)
Differential
Differential
Voltage In
CMOS In Encode Select Input: The TTL compatible CMOS Encode Select input
CMOS In Loopback Enable: TTL compatible CMOS Loopback Enable input pin
ECL Out
ECL Out
Current
Current
Supply
Supply
Supply
Supply
Supply
Supply
Supply
ECL In
Type
Out
Out
Vcc: Positive power supply for the ECL compatible circuitry. The
Transceiver operates from a single +5VDC power supply.
GND: Return path for the ECL compatible circuitry power supply.
Receive Vcc: Positive power supply for the small signal receive circuitry.
This power supply is intentionally separated from others to eliminate
receive errors due to coupled supply noise.
Receive GND: Return path for the receive power supply circuitry. This
power supply return is intentionally separated from others to eliminate
receive errors due to coupled supply noise.
Transmit Vcc: Positive power supply required by the analog portion of the
transmit circuitry. This power supply is intentionally separated from the
others to prevent supply noise from coupling to the transmit outputs.
Transmit GND: Return path for the analog transmit power supply circuitry.
This supply return is intentionally separated from others to prevent supply
noise from being coupled to the transmit outputs.
External Vcc: Positive power supply for ECL output circuitry.
Receive Data Inputs: Balanced differential line receiver inputs.
Physical Media Indicate Data: Differential ECL compatible outputs
source the recovered receive data back to the Physical Layer device or to
a separate clock recovery device.
Physical Media Request Data: Differential ECL compatible inputs which
receive data from Physical Layer Device.
Transmit Data Outputs: Differential current driver outputs which drive
MLT-3 encoded data over twisted pair cable. These outputs provide
controlled rise and fall times designed to filter the transmitters output which
helps to reduce associated EMI.
Signal Detect Outputs: Differential ECL compatible Signal Detect outputs
indicating that either a signal with the proper amplitude is present at the
RXI+/- inputs or that Loopback mode has been selected.
Transmit Amplitude Reference: Reference current pin allowing
adjustment of TXO+/- transmit amplitude. By placing a resistor between
this pin and GND, a reference current is setup which results in a given
transmit amplitude for a given application. Refer to Functional Description
in Section 3.1 for reference current equations.
controls the encoded state of the signal at the TXO+/- outputs. A logic low
level at this input causes the TXO outputs to become MLT-3 encoded with
the receiver programmed to accept MLT-3 encoded data. This is the
recommended mode of operation. A logic high level causes the TXO pins
to output standard two-level binary code and the receiver is conditioned to
receive a two-level binary signal. The DP83223V does not guarantee this
mode(binary) of operation.
selects the internal loopback path which routes the PMRD+/- data to the
PMID+/- differential outputs and forces Signal Detect true. During
loopback, data present at the RXI+/- inputs is ignored. However, binary
data is still transmitted by the TXO+/- outputs (regardless of the state of the
ENCSEL input). Loopback mode is selected when LBEN is forced high.
Normal operation occurs when LBEN is forced low.
4
Description