tza3015hw NXP Semiconductors, tza3015hw Datasheet - Page 12

• Manufacturer Part Number: tza3015hw
• Description: 30 Mbit/s To 3.2 Gbit/s A-rate 4-bit Fibre Optic Transceiver
• Manufacturer: NXP Semiconductors

Philips Semiconductors
DCR programming
Programming the DCR involves four dividers:
The first step is to determine in which octave the desired
bit rate fits, see Fig.7 and Tables 4 and 5. Figure 7 shows
the position of the most commonly used line rates in
relation to the defined octaves of the TZA3015HW.
Table 5 lists the most commonly used standards together
with the associated line rates. Table 4 clarifies the octave
definitions. This yields the value for the octave divider M.
The value for R is determined by the reference frequency
and the received bit rate (see Section “Reference clock
programming”).
Table 4 Octave definition
2003 Dec 16
handbook, halfpage
OCTAVE
Reference divider R
Main divider N
Fractional divider K
Octave divider M.
30 Mbit/s to 3.2 Gbit/s A-rate
4-bit fibre optic transceiver
28.125 56.25 112.5
Fig.7
0
1
2
3
4
5
6
6
Commonly used line rates and allocation of
octaves along a logarithmic bit rate scale.
5
16
32
64
M
1
2
4
8
4
RATE (Mbit/s)
LOWEST BIT
225
28.125
112.5
56.25
1800
900
450
225
3
450
2
900
RATE (Mbit/s)
HIGHEST BIT
1
1800
Mbits/s
112.5
56.25
3200
1800
900
450
225
0
MGU316
3200
12
Table 5 Most-common optical transmission protocols
The values for N and K are derived from the division
ratio (n.k). The division ratio (n.k) can be calculated with
the following formula:
where:
n.k
10GE
2xHDTV
STM16/OC48 + FEC
STM16/OC48
DV-6000
Fibre Channel
HDTV
D-1 video
DV-6010
Gigabit Ethernet
Fibre Channel
OptiConnect
ISC
STM4/OC12
DV-6400
Fibre Channel
OptiConnect
Fibre Channel
ESCON/SBCON
STM1/OC3
FDDI
Fast Ethernet
Fibre Channel
OC1
n = integer part of the division ratio
k = fractional part of the division ratio
bit rate = bit rate at serial input in Mbit/s
M = octave divider M
R = reference divider R
f
ref
=
= reference frequency in MHz.
bit rate M R
--------------------------------------- -
PROTOCOL
f
ref
BIT RATE
3125.00
2970.00
2666.06
2488.32
2380.00
2125.00
1485.00
1380.00
1300.00
1250.00
1062.50
1062.50
1062.50
(Mbit/s)
622.08
595.00
425.00
265.63
212.50
200.00
155.52
125.00
125.00
106.25
51.84
Preliminary specification
TZA3015HW
OCTAVE
0
0
0
0
0
0
1
1
1
1
1
1
1
2
2
3
3
4
4
4
4
4
5
6