TZA3047AVH PHILIPS [NXP Semiconductors], TZA3047AVH Datasheet - Page 16

• Manufacturer Part Number: TZA3047AVH
• Description: 30 Mbits/s up to 1.25 Gbits/s laser drivers
• Manufacturer: PHILIPS [NXP Semiconductors]

Philips Semiconductors
12.1.3
The dual-loop control measures the monitor current (I
corresponding with an optical ‘one’ level and the I
corresponding with the optical ‘zero’ level. The measured
I
monitor current setting and the extinction ratio setting
according to:
The dual-loop controls the bias and the modulation current
for obtaining the I
which correspond with the programmed AVR and ER
settings.
2003 Jun 05
I
ER
MON(one)
handbook, full pagewidth
av(MON)
30 Mbits/s up to 1.25 Gbits/s laser drivers
=
----------------------- -
I
I
MON(zero)
MON(one)
D
=
and I
UAL
I
---------------------------------------------------- -
MON(one)
-
MON(zero)
LOOP CONTROL
MON(one)
Fig.5 Average monitor current and extinction ratio as a function of I
+
2
I
are compared with the average
MON(zero)
I av(MON)
( A)
and I
1500
30
0
MON(zero)
15
10
5
ER
15
30
ER = 20
current levels
I ER
2 A
MON
MON
)
16
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 (1.25 Gbits/s).
The operational area of the dual-loop and the control area
of the monitor input current must respect the following
equations:
250 A I
Stability of ER and AVR settings are guaranteed over a
range of temperature and supply voltage variations.
50 A I
I av(MON) = 1580
MON(zero)
MON(one)
I AVR ( A)
I ER ( A)
500 A
TZA3047A; TZA3047B
2500 A
5.26
295
AVR
I AVR A
MGT892
and I
ER
Product specification
.