tza3011a NXP Semiconductors, tza3011a Datasheet - Page 18

• Manufacturer Part Number: tza3011a
• Description: 30 Mbit/s Up To 3.2 Gbit/s A-rate Tm Laser Drivers
• Manufacturer: NXP Semiconductors

Philips Semiconductors
9397 750 14437
Product data sheet
12.1.2 Average monitor current and extinction ratio
The average monitor current I
by the source current (I
current source or by an external resistor (R
The extinction ratio in dual-loop operation is determined by the source current (I
ER pin. The current can be sunk by an external current source or by an external resistor
(R
The average monitor current and the extinction ratio as a function of the I
current are illustrated in
The average monitor current increases with a decreasing I
allows resistor tuning of R
The formulas used to program AVR and ER are valid for typical conditions; tuning is
necessary to achieve good absolute accuracy of AVR and ER values.
I
av MON
Fig 6. Average monitor current and extinction ratio as a function of I
ER
) connected to ground:
=
I
1580 5.26
av(MON)
( A)
1500
30
–
0
15
10
5
ER
15
Rev. 06 — 20 January 2005
AVR
Figure
30
I
ER = 20
AVR
AVR
) of the AVR pin. The current can be sunk by an external
ER
av(MON)
to start at minimum I
=
6.
=
1580 5.26
2 A
I
ER
20
in dual-loop or average loop operation is determined
–
–
----------- -
2 A
30 Mbit/s up to 3.2 Gbit/s A-rate
I
ER
TZA3011A; TZA3011B
AVR
=
) connected to ground:
V
------------ -
R
20
AVR
AVR
–
AVR
----------- -
2 A
[ A]
I
av(MON)
1
current level.
AVR
© Koninklijke Philips Electronics N.V. 2005. All rights reserved.
I
I
AVR
ER
= 1580
V
--------- -
R
ER
ER
( A)
or increasing R
( A)
5.26
AVR
295
I
AVR
and I
AVR
mgt892
A
laser drivers
and I
ER
AVR
ER
, this
) of the
ER
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