DS1862AB+ Maxim Integrated Products, DS1862AB+ Datasheet - Page 18

• Manufacturer Part Number: DS1862AB+
• Description: IC LASR CTRLR 7CHAN 5.5V 25CSBGA
• Manufacturer: Maxim Integrated Products
• Type: Laser Diode Controller (Fiber Optic)r

Specifications of DS1862AB+

• Data Rate: 10Gbps
• Number Of Channels: 7
• Voltage - Supply: 2.9 V ~ 5.5 V
• Current - Supply: 3mA
• Operating Temperature: -40°C ~ 100°C
• Package / Case: 25-CSBGA
• Mounting Type: Surface Mount
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

XFP Laser Control and Digital Diagnostic IC
Table 5. AUX1/2MON Functionality
Selection (Unit Selection)
fault functionality, current on the BIASSET pin is moni-
tored by the DS1862A to control the HIGH BIAS quick-
trip alarm. Similar to TX-P, the RSSI pin is used to
measure the received power, RX-P.
AUX1MON and AUX2MON are auxiliary monitor inputs
that may be used to measure additional parameters.
AUX1/2MON feature a user-selectable register that
determines the measured value’s units (i.e., voltage,
current, or temperature). In addition to indicating units,
some of the 4-bit op codes, in Table 5, also place the
part in special modes used for alarms and faults inter-
nally. Whichever units’ scale is selected, the DS1862A
is only capable of measuring a positive voltage quanti-
18
VALUE
0000b
0001b
0010b
0011b
0100b
0101b
0110b
0111b
1000b
1001b
1010b
1101b
1110b
1111b
______________________________________________________________________________________
Auxiliary monitoring not implemented
APD bias voltage (16-bit value is voltage in units
of 10mV)
Reserved
TEC current (mA) (16-bit value is current in units
of 0.1mA)
Laser temperature (same encoding as module
temperature)
Laser wavelength
+5V supply voltage (encoded as primary voltage
monitor)
+3.3V supply voltage (encoded as primary
voltage monitor)
+1.8V supply voltage (encoded as primary
voltage monitor) (V
-5.2V supply voltage (encoded as primary voltage
monitor)
+5V supply current (16-bit value is current in
0.1mA)
+3.3V supply current (16-bit value is current in
0.1mA)
+1.8V supply current (16-bit value is current in
0.1mA)
-5.2V supply current (16-bit value is current in
0.1mA)
DESCRIPTION OF AUX1/2MON INTENDED USE
using AUX1MON and AUX2MON
(UNITS OF MEASURE)
Measuring Voltage Quantities
CC2
)
Table 6. A/D Conversion Example
Table 7. Temperature Bit Weights
ty, therefore internal or external calibration may be
required to get the binary value to match the measured
quantity. A table of acceptable units and/or their corre-
sponding user-programmable 4-bit op code is provid-
ed below.
All of the monitor channels feature alarm and warning
flags that are asserted automatically as user-pro-
grammed thresholds are internally compared with mon-
itor channel results. Flags may be set, which, if not
masked, will generate an interrupt on the INTERRUPT
pin or generate a safety fault. Whenever V
AUX2MON, AUX1MON, RSSI, and internal temperature
go beyond their threshold trip points and the corre-
sponding mask bit is 0, an interrupt is generated on the
INTERRUPT pin and a corresponding warning or alarm
flag is set. Similarly, a safety fault occurs whenever
BMD or BIASSET go beyond threshold trip points.
When this happens, the FETG pin immediately asserts
and BIASSET and MODSET currents are shut down.
Table 6 provides an example of how a 16-bit ADC code
corresponds to a real life measured voltage using the
factory-set calibration on either RSSI or IBIASMON. By
factory default, the LSB is set to 38.147μV.
To calculate V
convert the unsigned 16-bit value to decimal and multi-
ply by 100μV.
To calculate the temperature (internal), treat the two’s-
complement value binary number as an unsigned
binary number, then convert it to decimal and divide by
256. If the result is grater than or equal to 128, subtract
256 from the result.
Temperature: high byte = -128°C to +127°C signed;
low byte = 1/256°C.
S
2
-1
MSB (BIN)
11000000
10000000
Monitor Channel Conversion Example
2
2
6
-2
2
2
CC2
5
-3
, V
2
2
CC3
LSB (BIN)
00000000
10000000
4
-4
Based on Monitor Channels
, AUX1MON, or AUX2MON,
Alarms and Warning Flags
2
2
3
-5
2
2
—
VOLTAGE (V)
2
1.875
1.255
1
—
CC2/3
2
0
—
,