tza3011a NXP Semiconductors, tza3011a Datasheet - Page 19

• 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
12.1.3 Dual-loop control
12.1.4 Alarm operating current
The dual-loop control measures the monitor current (I
‘one’ level and the I
and I
ratio setting according to:
The dual-loop controls the bias and the modulation current for obtaining the I
I
Performance of the dual-loop for high data-rate is linked to the quality of the incoming
IMON signal: a high performance interconnection between monitor photodiode and MON
input is requested for maximum data rate applications (2.7 Gbit/s).
The operational area of the dual-loop and the control area of the monitor input current
must respect the following equations:
Stability of ER and AVR settings are guaranteed over a range of temperature and supply
voltage variations.
The alarm threshold I
current I
which corresponds with an I
sunk by an external current source or by connecting R
The operating current equals the bias current for an AC-coupled laser application and
equals the bias current plus half of the modulation current for the DC-coupled laser
application:
I
ER
50 A
250 A
I
I
I
MON(zero)
av MON
oper alarm
oper TZA3011 A
oper TZA3011B
=
MON(zero)
------------------------- -
I
I
MON zero
MON one
MAXOP
I
MON zero
current levels which correspond with the programmed AVR and ER settings.
I
=
MON one
=
I
-------------------------------------------------------- -
MON one
are compared with the average monitor current setting and the extinction
N
of the MAXOP pin. The current range for I
=
=
MAXOP
I
I
BIAS
BIAS
MON
500 A
2500 A
oper(alarm)
Rev. 06 — 20 January 2005
+
2
+
corresponding with the optical ‘zero’ level. The measured I
I
MON zero
V
-------------------- -
R
I
---------- -
mod
MAXOP
MAXOP
2
oper(alarm)
on the operating current is determined by the source
from 7.5 mA to 150 mA. The I
30 Mbit/s up to 3.2 Gbit/s A-rate
TZA3011A; TZA3011B
MON
MAXOP
MAXOP
) corresponding with an optical
© Koninklijke Philips Electronics N.V. 2005. All rights reserved.
to ground:
is from 10 A to 200 A
MAXOP
current can be
laser drivers
MON(one)
MON(one)
19 of 30
and