Users’ Instruction for
Universal DPMZ /DP-QPSK Modulator Bias Controller (0188)
for all Applications
(09/18/2015, V1.0)
Features of the Universal DPMZ/DP-QPSK MBC (0188)
Table 1. The Universal DPMZ/DP-QPSK MBC Specifications
0188 Layout
Table 2Electrical interface pin-out and function with multiple options for biasing and phase control.
Connectors and Jumpers:
Table 3. Connector J1 --- power supply input.
Communication.
Table 4. Commands to set working point and check status
Special functions (manual mode):
Table 5. Commands to enable or disable Pilot tone
Table 7. Indicator
Major Application
The universal DPMZ/DP-QPSKModulator Bias Controller model 0188 is a device specially designed to control the bias positions for DPMZ or SP-QPSK and DP-QPSK modulator. 0188 can control two polarization channels in DP-QPSK modulator, it also can only control one polarization channels in DPMZ modulator.
YY Labs’ Universal DPMZ/DP-QPSK modulator bias controller (0188) is a full-function miniature OEM version of the Modulator Bias Controller (MBC) family. It simultaneously sets the first and second modulators of each QPSK modulator at Null points and the third modulator of each QPSK modulator at quad point. There are USB and RS232 computer interfaces. The slope of each point is selectable from the computer.
The universal DPMZ modulator bias controller 0188 is not sensitive to the RF signal patterns and RF amplitudes. Therefore, it can work with not only DQPSK, but also very small QAM signals. It uses the modulator built-in PDs.
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Figure 1. Modulator working function
Features of the Universal DPMZ/DP-QPSK MBC (0158)
- Six modulators can be controlled with one controller
- No external PD needed
- Independent of RF modulation, very wide range of RF signal Amplitude
- Bias position will be displayed graphically through the GUI.
- The Unit serial number can be read through GUI.
- All settings are remote controllable through USB or RS232 computer interface
- Low profile (3.80” * 2.50” * 0.65”).
Table 1. MBC 0188 Specifications
PARAMETERS / MIN / TYP / MAX / UNITSOptical Performance
Detector Input Power1 / -30 / -10 / dBm
Optical wavelength / 1000 / 1650 / nm
Electrical Performance
Bias voltage (differential only) / -15 / 15 / V
Null Mode Extinction Ratio2 / 25 / 40 / dB
Locking Slope / Positive or Negative
Locking Mode / 4 Null (Peak) or Quad positions,
Quad+ or (Quad-) position
Pilot tone
Modulation Depth (QUAD)3 / 100mv / 1.5 %
Modulation Depth (Null) / 0.2 / %
Pilot Tone Frequency / 4K/2K* / Hz
Power Supplies
Positive Power Voltage / 14.5 / 15 / 15.5 / V(DC)
Negative Power Voltage / -15.5 / -15 / -14.5 / V(DC)
Positive Power Current / 100 / mA(DC)
Negative Power Current / 60 / mA(DC)
General
Operating temperature / 0 / 70 / Degree C
Storage Temperature / -40 / +85 / Degree C
Dimension / 3.80x2.50x0.65 inch
Weight / 0.2 lb
* 4KHz pilot tone is for the 1st and 2nd of the QPSK modulators and 2KHz pilot tone is for the 3rd of the QPSK modulators.
For a given input, detection power refers to optical power to the photodiode of MBC when the modulator output is at its minimum attenuation (The detection power does not describe the detected power at locking status).
The extinction ratio will be close but not exceed the extinction ratio of the modulator.
Optical Modulation Index = amplitude of modulation/V.
0188 Layout
Figure 2. Layout of 0188
Figure 3. Location of the datum and envelope related
Dimensions of related DP QPSK modulator
Figure 4. Mechanical specification of DC and GPPO RF interfaces
The pin-out of the Connector of the 0188 MBC is made according to the OIF-2009 specification. The DP-QPSK modulator can be directly plugged into the connector. The mechanical specification of the DP-QPSK modulator with four GPPO high-speed interfaces and 18 low-speed pins is shown in Figure 3. The low-speed pins are grouped in groups of 6 pins.
The pin numbering starts with the first high-speed data interface connector nearest to the input and the pin number increases towards the opposite side. The electrical interface grouping, ordering and functions of commercially available modulators are listed in Table-1.
Figure-5 DP QPSK modulator numbering for 0158 MBC
Table 2Electrical interface pin-out and function with multiple options for biasing and phase control.
Pin / Description1 / X-polarization in-phase data input
2 / X-polarization quadrature data input
3 / Y-polarization in-phase data input
4 / Y-polarization quadrature data input
5 / Bias_Y/Q(p) / Y/Q modulator (positive) bias
6 / Bias_Y/Q(n) / Y/Q modulator (negative) bias
7 / Bias_Y/I(p) / Y/I modulator (positive) bias
8 / Bias_Y/I(n) / Y/I modulator (negative) bias
9 / Bias_X/Q(p) / X/Q modulator (positive) bias
10 / Bias_X/Q(n) / X/Q modulator (negative) bias
11 / Bias_X/I(p) / X/I modulator (positive) bias
12 / Bias_X/I(n) / X/I modulator (negative) bias
13 / Phase_Y(p) / Y pol. phase (positive)
14 / Phase_Y(n) / Y pol. phase (negative)
15 / Phase_X(p) / X pol. phase (positive)
16 / Phase_X(n) / X pol. phase (negative)
17 / Not Connected
18 / Y-polarization photodiode Anode
19 / Y-polarization photodiode Cathode
20 / Ground
21 / X-polarization photodiode Cathode
22 / X-polarization photodiode Anode
Connectors and Jumpers:
J1 ----- 3-pin terminal for power supply entry
Table 3. Connector J1 --- power supply input.
Pins / Color / Description1 / Green / Com
2 / Brown / -15VDC (+/- 0.5V) @ 70mA
3 / Yellow / +15VDC (+/-0.5V) @ 100mA
JP1 ----- Connector for Modulator Biases and PDs
The port has the same pin-out as the DP-QPSK modulator( as Table-2). 0188can provide both differential and single-endedbias outputs.
If the biases on modulator aredifferential, the positive bias pins on the modulator should be connected with the positive bias outputs on the Board, the negative bias pins on the modulator should be connected with the negative bias output pins on the Board. Then, select Bias Output Mode to “Differential” using GUI.
If the biases on modulator are single-ended, connect the bias pins on the modulator with the positive bias output pins on the board, and connect the ground on the modulator with the ground pin on the board (Pin20 of JP1). Then, select thebias output mode to “Single End” using GUI.
JP2 ----- Calibration Mode Selection
Pins status
/ Description1,2 short / Calibration mode. A calibration process will be always started when power turns on or reset button is pressed.
2,3 short / No Calibration mode. The calibration process will not be initiated. Instead, the unit will use the stored V, bias and light intensity in the EEPROM to configure the circuitry and directly close the servo loop.
JP3 ----- USB connector. The USB connector is used for remote control through USB serial interface. Please connect this port to the computer to use GUI.
JP4 ----- Reserved for factory use
JP5 ----- RS232 output
JP6 ----- UART output
JP41---- Tuning mode selection for modulator YP
P41: Tuning pot for modulator YP
JP42---- Tuning mode selection for modulator XP
P42: Tuning pot for modulatorXP
If the locked bias position of YP or XP is not at the best point, the bias can be tuned to the best point by using JP41 or JP42. Please follow the following step to do the adjustment.
1. Open JP41 or JP42
2. Measure the center pin of P41 or P42 to ground, adjust the pot to set it to zero volt.
3. Short the JP41 or JP42.
4. Be Very gentle to tune the P41 or P42. Please tune it a little bit first, and wait for a few seconds, if not enough, adjust a little bit more.
Communication.
There is a USB connector on the board for communicating with PC. There is an RS232 output (JP5) and UART output (JP6). UART input is TTL level and output is CMOS level.
Table 4. Commands to set working point and check status
Commands / Commands Return / FunctionSSP / SMode:RF Vpp>1.8Vpi / Set board for RF Vpp>1.8Vpi
SSM / SMode:RF Vpp<1.5Vpi / Set board at RF Vpp<1.5Vpi
SSZ / SZ: Set Modulator parameters / Set Modulator parameters, see details in “Set Modulator parameters”
SSI / SI: differential bias / Set Bias as differential signal
SSi / Si: single end bias / Set Bias as single end signal
SSA / SA:negative slope / Set A Modulator At V2pi Null
SSa / SA:positive slope / Set A Modulator At Vpi Null
SSB / SB:negative slope / Set B Modulator At V2pi Null
SSb / SB:positive slope / Set B Modulator At Vpi Null
SSC / SC:Quad- / Set C Modulator At Quad+
SSc / SC:Quad+ / Set C Modulator At Quad-
SSD / SD:negative slope / Set D Modulator At V2pi Null
SSd / Sd:positive slope / Set D Modulator At Vpi Null
SSE / SE:negative slope / Set E Modulator At V2pi Null
SSe / Se:positive slope / Set E Modulator At Vpi Null
SSF / SF:Quad- / Set F Modulator At Quad-
SSf / Sf:Quad+ / Set F Modulator At Quad+
SSR / SR: Reset 0157JQ Board / Soft Reset 0157JQ Board
SSU / UA2256B3256 / Read PD input Power
For example, if the commands return shown as UA2256B3256
It means: Y PD Current 2.256uA
X PD current 3.256uA
SST / ST: Start Calibration / Calibration the board if the light intensity has been changed. The setting of the working modes of each modulator will not be changed when execute this command.
SSV / SV1.0 / Read software version.
For example, if the commands return shown as SV1.0
It means: the version is V1.0.
SSQ / SQ: Inquire the status of Modulator:
A-At V2pi/ Vpi Null
B-At V2pi/ Vpi Null
C-Quad+/-
D-At V2pi/ Vpi Null
E-At V2pi/ Vpi Null
F-Quad+/- / Inquire the status of Dual DPMZ Modulator. The return command shows the current status of the modulator being inquired
SKK / VVAA262BA171CA149DB81EA73FA1196 / Read the bias voltages of the six modulators. VV is the start words. Then the words show the voltages of six channels. The words ’A’ ‘B’ ’C’ ’D’ ’E’ ’F’ stand for the related modulators. The letter (A,B) just before the numbers represents negative or positive. A: Positive; B: negative. The numbers are the corresponding bias voltage, which has been timed by 100. For example, if the commands return shown as VVAA262BA171CA149DB81EA73FA1196
It means: Bias voltage:
AA262: +2.62V
BA171: +1.71V
CA149: +1.49V
DB81: -0.81V
EA73: +0.73V
FA1196: + 11.96V
This command can also be used in the manual mode when the pilot tone is disabled.
Special functions (manual mode):
For user’s convenience, the pilot tones can be stopped to any or all selected modulators; the user then can manually set the bias voltage of that modulator through USB or RS232 interface.
Commands to disable pilot tone. The commands are listed in the following table.
Table 5. Commands to enable or disable Pilot tone
Commands / Commands Return / FunctionSMA / MA: BiasA without Pilot tone / Set Bias of A Modulator at current voltage
SMa / Ma: BiasA with Pilot tone / Enable the pilot tone on BiasA
SMB / MB: BiasB without Pilot tone / Set Bias of B Modulator at current voltage
SMb / Mb: BiasB with Pilot tone / Enable the pilot tone on BiasB
SMC / MC: BiasC without Pilot tone / Set Bias of C Modulator at current voltage
SMc / Mc: BiasC with Pilot tone / Enable the pilot tone on BiasC
SMD / MD: BiasD without Pilot tone / Set Bias of D Modulator at current voltage
SMd / Md: BiasD with Pilot tone / Enable the pilot tone on BiasD
SME / ME: BiasE without Pilot tone / Set Bias of E Modulator at current voltage
SMe / Me: BiasE with Pilot tone / Enable the pilot tone on BiasE
SMF / MF: BiasF without Pilot tone / Set Bias of F Modulator at current voltage
SMf / Mf: BiasF with Pilot tone / Enable the pilot tone on BiasF
Commands to set voltage.
When in the manual mode (disable the pilot tone), user can set the bias voltage.
The command is: S + channel + A(positive) or B(negative) + voltage to be set which has been timed by 100.
Then the command return is: channel + A(positive) or B(negative) + set voltage which has been timed by 100.
For example:
To set A channel at 5.56v:
Send order: SAA556 Command returns: AA554
To set E channel at -10.91v
Send order: SEB1091 Command returns: EB1090
Note: The above commands only work at the manual mode. Send the command to disable the pilot tone first and then set the voltage. Otherwise, the command will not work. The command to read bias voltage can also work in the manual mode.
Commands to input modulator Parameters including Null positions for Q, I, and Quad position for P modulator.
With QAM application, sometime the user does not have a 2Vpi PRBS RF signal for doing calibration, this function is for the user to manually input the known Null bias positions for Q and I modulators and the Quad position for P modulator. Calibration will not be required.
First send “SSZ” command to MBC Board, and the board will return “SZ: Set Modulator parameters”. Then send the modulator parameters after the SSZ command. The delay should be no more than 5s. The modulator parameters have the following format:
A( or B)# # # # A(or B) # # # #A(or B)# # # # A(or B) # # # # A(or B) # # # #A(or B)# # # # # # # # # # # # # # # # # # # # # # # # # # # #
A means the value is positive, B means the value is negative. The digits is the corresponding voltage which timed by 100.
For Example, send A0222B0333A0444B0555A0666B0777111122223333444455556666
It means: YQ Null at 2.22V, YI Null at -3.33V,YP Quad at 4.44V,XQ Null at -5.55V,XI Null at 6.66V,XP Quad at -7.77V, YQ Vpi is 11.11V,YI Vpi is 22.22V,YP Vpi is 33.33V,XQ Vpi is 44.44V,XI Vpi is 55.55V,XPVpi is 66.66V
Table 7. Indicator
Status / ExplanationRed / No light / Light is too weak / Bias is not connected /light is too strong
Flashing Green / In calibration process , YP or XP is not locked
Green / Locking status is normal.
Major Application
Typical Application:
Suggesting working procedure:
- Connect the system as shown in Typical Application.
- Short Pin 1and Pin2 of JP1, Open JP41 and JP42.
- Turn the power on. If red led flash, that mean the light is too small or too strong. If green led flash, that mean the board is locking.
- Wait one minute, and then check if the bias has been locked to right point. If it is not right, connect the board with computer and check which bias is not locked using GUI. The default mode of the board is for Vpp RF <1.5Vpi, If the Vpp of RF is more than 1.8 Vpi, the mode need to be changed using GUI.
- If all the bias of all modulators is stable and the eye diagram of the output is not so good, applying an offset on Bias YP or YP by tuning the P41 0r P42 will help. Please see the details on Page 4 and Page 5 about how to tune P41 or P42.
The pot P41 and P42 need to be adjusted again when the input optical power has changed, or the RF amplitude has changed, or the modulator has changed.
- If YP or XP bias is not stable, sometimes increasing pilot tone will help. Because the pilot tone is proportional to the Vpi of modulator, setting the vpi of the modulator a little bigger, the pilot tone will get bigger automatically.
- If the RF<1.5Vpi, the board sometimes cannot find the right point during Calibration, but it will continue to look for after the calibration and the green LED will keep flashing until it find the right point.
Note: For DPMZ Modulator, if there is no PD in the modulator, please use a 1% Coupler after the output of the Modulator, and connect the 1% output of the coupler with one PD. Then connect the output of the PD with relative input pin on JP1.
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