DS1861B+ Maxim Integrated Products, DS1861B+ Datasheet - Page 16

• Manufacturer Part Number: DS1861B+
• Description: IC LASR CTRLR 1CHAN 5.5V 16CSBGA
• Manufacturer: Maxim Integrated Products
• Type: Laser Diode Controller (Fiber Optic)r

Specifications of DS1861B+

• Number Of Channels: 1
• Voltage - Supply: 2.85 V ~ 5.5 V
• Current - Supply: 5mA
• Operating Temperature: -40°C ~ 95°C
• Package / Case: 16-CSBGA
• Mounting Type: Surface Mount
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Full Laser Control with Fault Management
Figure 12. Setting N Using the ER Register
Figure 13. Quick Trip Logic Diagram
16
HBIAS ENABLE
HBIAS ALARM
HTXP ENABLE
LTXP ENABLE
HTXP ALARM
LTXP ALARM
SOFT TX-D
____________________________________________________________________
TX-D
POA
144
128
112
96
80
64
48
32
16
0
NOTE: POA IS HIGH WHEN V
INVALID
27 28
ER REGISTER SETTING (DECIMAL)
SETTINGS SHADED
INVALID ER
CC
< V
D
S
POA
R
Q
Q
SHUTDOWN
.
HBIAS
104 105
INVALID
D
S
R
Q
Q
SHUTDOWN
127
HTXP
D
S
R
Q
Q
SHUTDOWN
LTXP
The average power current is defined as the difference
between the current required to reach the average
power output and the threshold current of the laser
diode. The average power output is defined as the
mean of the power used to transmit a high logic level
(P1) and the power used to transmit a low power level
(P0). Figure 10 graphically shows the threshold and
average power currents as they relate to the light out-
put of a laser diode.
The DS1861 has a V
ble quick-trip (QT) fault monitors (Figure 13) that can
trigger the TX-F output. The QTs monitor for high trans-
mit power (HTXP), low transmit power (LTXP), and for
high bias current (HBIAS). All the QTs feature program-
mable trip levels, an alarm disable, and a shutdown
enable to determine if the enabled QT alarm shuts off
the I
V
ensure that V
CC
BIASSET
is monitored against two internal voltage levels to
and I
CC
is at an adequate level for the part to
Fault Monitors and Shutdown
MODSET
MODLOAD
QUICKSTART
CC
ENABLE
IN
monitor plus three programma-
RST
FAULT RESET TIMER
outputs.
OUT
IN
CONTROL
(130ms)
LOGIC
SHUTDOWN
FLAG
OUT
MODSET
BIASSET
TX-F