NWK914D
1KΩ
Xtal Osc.
R1
100pF
C1
LFTA
REFCLK
LFTB TXREF
.033µF
C2
See Table 2 for
these resistor values
TxV
cc
R2
R5
TXGND
TXOP
0.1µF
PCS
or
MAC
(with
embedded
PCS)
5
TDAT0-4
TXON
TXC
RXC
C4
CT
1:1
M
A
G
N
E
T
I
C
S
R6
NWK914D
RXIP
R9
15Ω
R7
68Ω
R8
15Ω
RJ45
5
RDAT0-4
LFRA
LFRB
C3
R3
6.2KΩ
.01µF
RXIN
Fig.6 Simplified 100BASE-TX system block diagram showing NWK914D external components
REF.
C1
C2
C3
R1
R2
R3
R5,R6
R7,R8
R9
R2
R5,R6
VALUE
100pF
0.033µF
.01µF
1KΩ
1300Ω
6.2KΩ
50Ω
15Ω
68Ω
2.6KΩ
200Ω
TOL.
20%
20%
20%
1%
1%
1%
1%
1%
1%
1%
1%
FUNC.
loop fltr
loop fltr
loop fltr
loop fltr
tx ref
loop fltr
xmit
rcv pad
rcv pad
tx ref
xmit
1:1 magnetics
1:1 magnetics
NOTES
EXTERNAL REQUIREMENTS
The NWK914D requires a number of external components
for the device to function correctly and these are shown in
the simplified 100BASE-TX application circuit in Fig.6 and
the component value information given in Table 2.
Note that the values of R2, R5 and R6 vary depending
upon application. When using 1:1 magnetics, use the values
shown in the middle of Table 2 with note "1:1 magnetics".
When using 2:1 magnetics use the values shown in the last
two lines of Table 2. Please refer to the Transmit Line Driver
section on pages 3-4 for more information on these values.
For more detailed Application information please contact
your local Sales Office.
2:1 magnetics
2:1 magnetics
2:1 magnetics
GLOSSARY OF TERMS AND ABREVIATIONS
MAC
MLT-3
NRZ
NRZI
PCS
PHY
PLL
PMD
UTP
RX
STP
TX
UTP
VCO
Media Access Control
Multi Level Transmit -3 levels
Non Return To Zero
Non Return to Zero Inverse
Physical Coding Sublayer
PHYsical Layer
Phase Locked Loop
Physical Media Dependent
Unshielded Twisted Pair
Receive
Shielded Twisted Pair
Transmit
Unshielded Twisted Pair
Voltage Controlled Oscillator
NWK914S
improved to 100m
680Ω
NWK914D
improved to 100m
1300Ω
CT on transformer connects directly to
TX V
CC
with C4 omitted
Table 2: External components
NWK914B
Base Line Wander Correction
TXREF resistor with 1:1 magnetics
-
620Ω
Table 3: Differences between NWK914B, NWK914S and NWK914D
7
MITEL [ MITEL NETWORKS CORPORATION ]
