TZA3047BVH/C1,551 NXP Semiconductors, TZA3047BVH/C1,551 Datasheet - Page 15

• Manufacturer Part Number: TZA3047BVH/C1,551
• Description: IC LASER DRIVER 1.25GBPS 32-HBCC
• Manufacturer: NXP Semiconductors
• Type: Laser Diode Driver (Fiber Optic)r

Specifications of TZA3047BVH/C1,551

• Data Rate: 1.25Gbps
• Number Of Channels: 1
• Voltage - Supply: 3.14 V ~ 3.47 V
• Current - Supply: 40mA
• Current - Modulation: 100mA
• Current - Bias: 100mA
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 32-HBCC
• Mounting Type: Surface Mount
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 568-1189; 935270561551; TZA3047BVHW-S

Philips Semiconductors
12 APPLICATION INFORMATION
12.1
12.1.1
The bias and modulation currents are determined by the
voltages on pins BIASIN and MODIN. These voltages are
applied by the BIASOUT and MODOUT pins for dual-loop
control. For average loop control the BIASIN voltage is
applied by the BIASOUT pin and the MODIN voltage is
applied by an external voltage source or an external
resistor R
For direct setting of bias and the modulation current, the
BIASIN and MODIN voltages have to be applied by
external voltage sources or by R
external resistors connected on BIASIN and MODIN pins:
I
I
The bias and modulation current sources operate with an
input voltage range from 0.5 to 1.5 V. The output current is
at its minimum level for an input voltage below 0.4 V;
see Figs 3 and 4.
The bias and modulation current sources are temperature
compensated and the adjusted current level remains
stable over the temperature range.
The bias and modulation currents increase with increasing
resistor values for R
allows resistor tuning to start at a minimum current level.
2003 Jun 05
BIAS
mod
handbook, halfpage
30 Mbits/s up to 1.25 Gbits/s laser drivers
Fig.3 Bias current as a function of BIASIN voltage.
= (R
I BIAS
= (R
(mA)
Design equations
110
0.2
MODIN
B
BIASIN
MODIN
0
IAS AND MODULATION CURRENTS
I BIAS(min)
.
100 A
100 A
BIASIN
0.5
g m(bias) =
110 mA/V
and R
0.5 V)
0.5 V)
V BIASIN (V)
BIASIN
MODIN
g
g
m(mod)
m(bias)
and R
respectively, this
+ 5 [mA]
[mA]
MODIN
1.5
MGT890
15
12.1.2
The average monitor current I
average loop operation is determined by the source
current (I
an external current source or by an external resistor (R
connected to ground:
I
The extinction ratio in dual-loop operation is determined by
the source current (I
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
The average monitor current increases with a decreasing
I
to start at minimum I
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.
ER
handbook, halfpage
av(MON)
AVR
I mod = I o(LA)
LA current when LA output is on.
V
Fig.4
o(LA)
=
or increasing R
(mA)
20
= V
= 1580
A
RATIO
AVR
105
–
ER
VERAGE MONITOR CURRENT AND EXTINCTION
CCO
Modulation current as a function of MODIN
voltage.
5
-------------- -
2 A
0
) of the AVR pin. The current can be sunk by
) connected to ground:
I
.
ER
I o(LA)(min)
AVR
5.26
=
and I
AVR
ER
AVR
TZA3047A; TZA3047B
20
) of the ER pin. The current can be
, this allows resistor tuning of R
0.5
–
ER
current level.
I
AVR
------------ -
2 A
g m(mod) =
100 mA/V
current are illustrated in Fig.5.
1
=1580
av(MON)
----------
R
V
V MODIN (V)
ER
ER
Product specification
in dual-loop or
5.26
------------- -
R
V
AVR
AVR
1.5
MGT891
AVR
AVR
A]
)