safety and warranty information
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1. 15 Om Lightwave SAFETY AND WARRANTY INFORMATION m El m El E E a El El El a E El E a a The Safety and Warranty Information section provides details about cautionary symbols used in the manual safety markings used on the instrument and information about the Warranty including Customer Service contact information Safety Information and the Manual Throughout this manual you will see the words Caution and Warning indicating potentially dangerous or hazardous situations which if not avoided could result in death serious or minor injury or damage to the product Specifically A CAUTION Caution indicates a potentially hazardous situation which can result in minor or moderate injury or damage to the product or equipment AY warning Warning indicates a potentially dangerous situation which can result in serious injury or death WARNING Visible and or invisible laser radiation Avoid direct exposure to the beam General Safety Considerations If any of the following conditions exist or are even suspected do not use the instrument until safe operation can be verified by trained service personnel Visible damage Severe transport stress Prolonged storage under adverse conditions Failure to perform intended measurements or functions If necessary return the instrument to ILX Lightwave or authorized local ILX Lightwave distributor for service or repair to ensure that safety2. Lightwave LDX 3412 m 1 2 LDX 3412 Product Overview GENERAL INFORMATION Specifications DRIVE CURRENT OUTPUT Output Current Range 0 to 200 mA Compliance Voltage 6 0 V Temperature Coefficient lt 100 ppm C Short Term Stability 1 hour lt 50 ppm Noise and Ripple 2 uA rms Transients 100 uA DRIVE CURRENT LIMIT SETTINGS Range 1 to 200 mA Accuracy 3 mA PHOTODIODE FEEDBACK Reverse Bias 0 5V adjustable PD Current Input Range 20 uA to 2 mA Stability gt 0 1 MEASUREMENT DISPLAY Display Type 3 1 2 digit green LED Output Current Range 0 to 199 9 mA Output Current Accuracy 0 2 LASER DIODE PROTECTION Output Shorting Switch Normally low impedance shunt Output Enable Delay 25 per 21CFR 1040 10 Current Limit Adjustable redundant hardware limit Error Monitoring Reporting Current limit open circuit GENERAL Power Requirements VAC 90 125 210 250 50 60 Hz Size 66mm x 140mm x 267mm 2 6 x 5 5 x 10 5 Weight 1 8 kg 4 0 Ibs Operating Temperature 0 C to 50 C Storage Temperature 40 C to 70 C Humidity lt 85 relative non condensing Laser Safety Interlock Output Delay meets CDRH US21 CFR 1040 10 CONNECTORS Current Source Output 9 pin D sub PD Input 9 pin D sub laser connector Chassis Ground
3. User s Guide har Precision Current Source N LDX 3412 OPEN LIMIT MODE CONST CONST LIMIT DISPLAY I TLX Lic nian A Newport Corporation Brand ILX Lightwave Corporation 31950 Frontage Road Bozeman MT U S A 59715 U S amp Canada 1 800 459 9459 International Inquiries 406 556 2481 Fax 406 586 9405 ilx custhelp com www ilxlightwave com 70001305 March 2011 TABLE OF CONTENTS a El L a Al Bl a El El EH EI El E El Table of i Safety and Warranty Information iii Safety Information and the iii General Safety Considerations iii Safety 15 iv Safety Marking Symbols iv 2 522 dere eda Set und V LIMITATIONS aiana heteste CR epe SH a se kved ete V Returning an V Claims for Shipping Damage vi Comments Suggestions and Problems vii Chapter 1 General Information Product Overview 1 Specifications dus got bd dl ul oca eee 2 Chapt
4. 4mm Banana Jack Interlock 9 pin D sub laser connector Lightwave RON GENERAL INFORMATION Product Overview All values relate to two hour warm up period with output enabled Over 10 to 30 minutes half scale output amp 25 ambient Half scale output measured electrically with a resistive load evaluating AC coupled rms value over 100 kHz bandwidth Maximum output current transient resulting from normal operations i e power on off current on off as well as accidental situations i e power line plug removal Testing to ILX Technical Standard LDC 00196 Maximum monitor photodiode current drift over any 30 minute period Assumes zero drift in photodiode responsivity 6 Measured at 25 C Our goal is to make the best laser diode instrumentation available anywhere To achieve this we need your ideas and comments on ways we can improve our products We invite you to contact us at any time with your suggestions 03 11 LDX 3412 n 3 GENERAL INFORMATION Product Overview 4 E LDX 3412 Lightwave CHAPTER 2 OPERATION m E mH H la a El El mH E m E a B E This chapter is guide to setting up and operating the LDX 3412 The controls and connectors are described and then step by step instructions for connecting and using the LDX 3412 are presented Installation Before plugging in the LDX 3412 to your AC power source AC Power Considerations
5. 6 Common Laser Anode Photodiode Cathode Module OUTPUT j Earth Ground Figure 2 7 Common Laser Anode Photodiode Anode If a feedback photodiode is used which is electrically isolated from the laser the feedback circuit must be resistively tied at some point to the output circuit A large resistance of 1 Mohm connected from the laser cathode to the photodiode anode may be used in place of the direct connection This is done to keep the feedback inputs within the specified maximum 6 volt common mode voltage relative to the laser current output terminal The circuit of Figure 2 5 should be used if feasible LDX 3412 m 11 12 OPERATION Installation Laser Diode Connections and Shielding A CAUTION LDX 3412 Before connecting the laser diode to the LDX 3412 be sure that the front panel OUTPUT switch is in the OFF position LED unlit Before turning on the OUTPUT be sure that the current LIMIT has been correctly set The LDX 3412 output is available through the 9 pin rear panel connector J105 The LDX 3412 sources current through pins 8 and 9 to the laser anode and returns current from cathode through pins 4 and 5 It is recommended that the connections to the LDX 3412 output be made using twisted wire pairs with an earth grounded shield see Figures 2 4 2 7 The output conductors are left floating relative to earth ground to suppress AC power on power off transients t
6. CONST P mode is selected turn the COARSE and FINE PD GAIN pots fully counter clockwise CCW This will initially maximize the feedback gain and minimize the Lightwave OPERATION Installation output current to the laser 7 Switch the OUTPUT on LED lit and adjust the current to the desired DC level using the main current setting knob Note If there is no output current at this point check to be sure that the proper interlock connections have been made If the interlock is enabled Pins 1 and 2 of J105 must be electrically connected before output current will flow In order to find the proper photodiode feedback gain for your laser in CONST P mode it will be necessary to follow these additional steps 8 With the output on slowly turn the FINE control clockwise CW until the proper feedback is reached Turning the GAIN controls clockwise CW will increase the output current If the FINE control is turned fully clockwise but the proper gain has not been reached continue with Step 9 9 Reset the FINE control to its fully counter clockwise CCW position Next slowly turn the COARSE control clockwise CW about 1 4 turn If the LIMIT LED becomes lit turn the COARSE control back down CCW a bit Then repeat Steps 8 and 9 as necessary Note At any time during the operation of the LDX 3412 the output current limit setting may be observed by selecting LIMIT DISPLAY mode In this mode the output current will be off and
7. features are maintained see the contact information on page vii All instruments returned to ILX Lightwave are required to have a Return Authorization Number assigned by an official representative of ILX Lightwave Corporation See Returning an Instrument on page v for more information um LX Lightwave Safety and Warranty Information iii koy DA SAFETY SYMBOLS This section describes the safety symbols and classifications Technical specifications including electrical ratings and weight are included within the manual See the Table of Contents to locate the specifications and other product information The following classifications are standard across all ILX Lightwave products Indoor use only Ordinary Protection This product is NOT protected against the harmful ingress of moisture Class I Equipment grounded type Mains supply voltage fluctuations are not to exceed 10 of the nominal supply voltage Pollution Degree Installation overvoltage Category II for transient overvoltages Maximum Relative Humidity lt 80 RH non condensing Operating temperature range of 0 xC to 40 xC Storage and transportation temperature of 140 xC to 70 xC Maximum altitude 3000 m 9843 ft This equipment is suitable for continuous operation Safety Marking Symbols This section provides description of the safety marking symbols that appear on the instrument These symbols provide information about potentially dangerous situations which
8. the current limit setting will be displayed on the LED display 03 11 LDX 3412 7 13 OPERATION 14 LDX 3412 Lightwave CHAPTER 3 TROUBLESHOOTING 5 B El a la a El El mH El B t El Li E a Calibration and line Voltage Selection require opening the case and exposure to potentially lethal voltages These procedures are to be performed by qualified Service personnel only Consult the factory for service instructions ILX Lightwave provides in house and on site calibration services for ILX instruments Most ILX instruments require yearly calibration to ensure performance to published specifications ILX factory calibrations employ NIST traceable measurement instrumentation and our calibration engineers and technicians use automated test equipment to accurately and efficiently capture and record calibration data An original certificate of calibration authenticity is provided with all instrument calibrations and a detailed report showing any pre calibration out of tolerance conditions is available upon request Calibration turn times are normally five business days or less On site calibrations can be performed around your production schedule night or day seven days a week Please contact ILX Customer Support see page Xi for contact information for additional calibration information Troubleshooting This appendix is a guide to troubleshooting the LDX 3412 Some of the more common symptoms are listed here and the approp
9. After power up make sure that the OUTPUT is off LED unlit For operating procedure see Operating Instructions on page 9 AC Power Considerations The LDX 3412 can be configured for operation with nominal line voltages of 100 120 220 and 240 VAG The unit is configured at the factory for the appropriate range Make sure the AC input power matches the range marked on the rear panel WARNING To avoid electrical shock hazard connect the instrument to properly earth grounded electical supply only Failure to observe this precaution can result in severe injury or death LDX 3412 Familiarization The following sections are provided to familiarize the user with features found on the LDX 3412 Lightwave LDX 3412 5 6 LDX 3412 OPERATION Installation Front Panel The LDX 3412 front panel is shown in Figure 2 1 ILXLightwave 3412 PRECISION CURRENT SOURCE LIMIT DIS LIMIT MODE POWER CONSTP CONST I LIMIT DISPLAY Figure 2 1 LDX 3412 Front Panel Power up Sequence With the LDX 3412 properly connected to an AC power source pressing the AC POWER off on switch causes the unit to initiate its power up sequence During this period the output terminals are unconditionally shorted and the OUTPUT off on switch is inhibited for two seconds This is done to prevent transients from reaching your laser diode Operating MODE Selection The MODE selec
10. UT off on switch after corrective action is taken if needed Fault Indicators The LDX 3412 has two visual front panel fault indicators OPEN CKT and LIMIT OPEN CKT indicates that the compliance voltage required at the LDX 3412 output terminals has exceeded approximately 6 volts Most commonly this happens when there is no load attached to the output or the load becomes disconnected when the output is active When an OPEN CKT condition occurs the LDX 3412 output is automatically turned off and LDX 3412 7 OPERATION Installation the OPEN CKT indicator latches on The OPEN CKT indicator will remain on until the output is manually turned on again LIMIT indicates that the LDX 3412 output is being limited to the setting of the front panel LIMIT knob When a LIMIT condition occurs the LIMIT indicator becomes lit The LIMIT DISPLAY indicator is not a fault indicator It is lit when the unit is operated in the LIMIT DISPLAY mode This is done to remind the user that LIMIT DISPLAY mode is in operation and the OUTPUT switch is inactive Rear Panel The rear panel contains the 9 pin D sub connector chassis ground post photodiode gain adjustment controls power cord receptacle and serial number sticker OUTPUT MIN MEX Lite LTAGE 240V FRED 50 50HZ PD GAIN COARSE FINE 20 O igro 3412bp 1 Figure 2 2 LDX 3412 Rear Panel 1 2 Interloc
11. can result in death injury or damage to the instrument and other components or I slash I only denotes that mains are on or Caution Earth Visible and or refer to ground EN invisible laser manual Terminal radiation Caution risk Protective Frame or of electric Conductor hot chassis shock Terminal Terminal dl On In position of a bistable push control The Off Out position of bistable push control The circle only denotes that mains are off iv Safety and Warranty Information Lightwave WARRANTY ILX LIGHTWAVE CORPORATION warrants this instrument to be free from defects in material and workmanship for period of one year from date of shipment During the warranty period ILX will repair or replace the unit at our option without charge Limitations This warranty does not apply to fuses lamps defects caused by abuse modifications or to use of the product for which it was not intended This warranty is in lieu of all other warranties expressed or implied including any implied warranty of merchantability or fitness for any particular purpose ILX Lightwave Corporation shall not be liable for any incidental special or consequential damages If a problem occurs please contact ILX Lightwave Corporation with the instrument s serial number and thoroughly describe the nature of the problem Returning an Instrument If an
12. cking list If the instrument is damaged file a claim with the carrier The factory will supply you with a quotation for estimated costs of repair You must negotiate and settle with the carrier for the amount of damage vi Safety and Warranty Information Ju Ix Lightwave Comments Suggestions and Problems To ensure that you get the most out of your ILX Lightwave product we ask that you direct any product operation or service related questions or comments to ILX Lightwave Customer Support You may contact us in whatever way is most convenient PHONG c tage deka dad 800 459 9459 or 406 586 1244 Fa 406 586 9405 Is P ERE support ilxlightwave com Or mail to ILX Lightwave Corporation P O Box 6310 Bozeman Montana U S A 59771 www ilxlightwave com When you contact us please have the following information Model Number Serial Number End user Name Company Phone Fax Description or sketch of what is connected to the ILX Lightwave instrument Description of the problem If ILX Lightwave determines that a return to the factory is necessary you are issued a Return Authorization RA number Please mark this number on the outside of the shipping box You or your shipping service are responsible for any shipping damage when returning the instrument to ILX Lightwave ILX recommends you insure the shipment If the original shipping container is not available place yo
13. diode feedback gain Warm up and Environmental Considerations The LDX 3412 should be operated at an ambient temperature between 0 and 50 C Storage temperatures should be in the range of 40 C to 70 C In order to achieve rated accuracy the LDX 3412 should be warmed up for 1 hour before use Note To prevent overheating the LDX 3412 must be kept well ventilated Allow at least 1 2 inch clearance around the vent holes Operating Instructions The following sections contain instructions on the set up and operation of the LDX 3412 Section 2 5 6 contains the step by step operating procedures For calibration see Section 4 2 Connecting to Your Device When connecting laser diodes and other sensitive devices to the LDX 3412 we recommend that the LDX 3412 be powered up and the OUTPUT be off LED unlit In this condition a low impedance shunt is active across the output 03_11 LDX 3412 9 OPERATION Installation terminals When disconnecting devices it is only necessary to turn the OUTPUT off System Interlock When the LDX 3412 is shipped an interlock is incorporated at connector J105 pins 1 and 2 Output current will not flow unless there is an electrical connection made between pins 1 and 2 of J105 When the interlock function is to be used the user must provide a normally closed switch or relay across pins 1 and 2 of the 9 pin connector J105 The switch must be electrically isolated from all other circuits
14. er 2 Operation Installation 5 Power Considerations 5 LDX 3412 Familiarization 5 Eront Panel ss 6 Power up Sequence 6 Operating MODE Selection 6 Current LIMIT Adjustment 6 Output Current Adjustment 7 OUTPUT Off On Switch 7 Fault IndiGators 2225 eere ace qs ea dab vocor eo de gx eder 7 hear P allele senno TN 8 Lightwave LDX 3412 i ko m a Output Connectors x ie seanse de ede def RE ER bee ad Rod 9 Chassis GND Connector 9 Photodiode Feedback PD GAIN 9 Warm up and Environmental Considerations 9 Operating Instructions 9 Connecting to Your Device 9 System Interlock 10 Photodiode Feedback Connections 10 Laser Diode Connections and Shielding 12 Grounding Considerations 12 General Operating Procedure 12 Chapter 3 Troubleshooting Troubleshooting
15. g the polarity of the photodiode OUTPUT intermittently turns off during operation Check the interlock circuit A broken circuit will reset the LDX 3412 to the off state Check that the AC power cord connection is secure Power drop outs may turn the OUTPUT off Check the AC line cord to make sure that it is well connected Lightwave
16. hat may occur through an earth ground path If the output circuit is earth grounded at some point such as through the laser package and mount the user must be careful to avoid multiple earth grounds in the circuit Multiple earth grounds may provide circuit paths that induce spurious currents in the photodiode feedback circuit and output leads Grounding Considerations The outputs of the LDX 3412 are isolated from chassis ground allowing either output terminal to be grounded at the user s option Figures 2 4 2 7 show the proper earth ground shielding for the most common laser diode photodiode connections General Operating Procedure The LDX 3412 can be operated in several modes The following operating procedure is applicable to most common usage 1 Plug the LDX 3412 into a properly grounded three terminal AC power source which supplies the correct voltage and frequency for your unit 2 Turn on the LDX 3412 allow a one hour warm up period for rated accuracy operation 3 Select the LIMIT DISPLAY MODE and adjust the LIMIT knob to the maximum current that you wish to source 4 Select the desired MODE of operation 5 With the OUTPUT off LED unlit make the necessary external circuit connections Double check to ensure that the correct polarity has been observed when connecting to laser diodes or other devices which are sensitive to being reversed biased For proper photodiode feedback connections refer to Section 2 5 3 6 Ifthe
17. he output is active the LED indicator just above the switch will be lit When the output is off a low impedance shunt is activated across the output terminals In this state it is safe to connect or disconnect sensitive devices from the LDX 3412 even though the power supply itself is on When the LDX 3412 is first turned on the OUTPUT off on switch is inhibited for several seconds This forces the internal low impedance shunt to remain active across the output terminals until the LDX 3412 control circuits are stabilized Additionally there are four other conditions which will automatically cause the output to reset to the off state Power Drop outs AC line power drop outs lasting more than about 10 msec will trigger an internal power monitor and cause the output to switch unconditionally to the off state This sequence is also initiated when the LDX 3412 is switched off or unplugged Open Circuit If the compliance voltage of the externally connected circuit exceeds about 6 volts the output is switched to the off state and the OPEN CKT indicator is activated Most commonly this occurs when the OUTPUT off on switch is pressed without a load attached Mode Changes Changing the position of the MODE selector switch resets the output to the off state Interlock If the interlock circuit is broken the output is reset to the off state If any of these conditions occur the output may be turned on again by simply pressing the OUTP
18. including earth ground Photodiode Feedback Connections The 9 pin connector J105 see pinout Figure 2 3 on the rear panel contains the current supply output and earth ground The photodiode feedback signal is input at the connector at pins 6 and 7 Many laser diode modules contain an internal photodiode that monitors the back facet emission of the laser This photodiode is usually internally connected to either the laser anode or cathode Figures 2 5 A D show the recommended connections and shielding for the various configurations of laser diode modules and photodiode feedback schemes The feedback photodiode reverse biasing supply shown in these figures must be supplied by the user You must locate this supply where it won t cause the common mode voltage of the feedback inputs to exceed the specified maximum of 6 V relative to the current output J105 pins 4 5 Noise from this biasing supply may contribute to the output noise levels therefore a battery with shielded connections is recommended OUTPUT Module 7 Bias LZ Earth Ground Figure 2 4 Common Laser Cathode Photodiode Cathode 10 LDX 3412 Lightwave 03_11 OPERATION Installation Module OUTPUT Bias 6 5 TH Earth Ground Figure 2 5 Common Laser Cathode Photodiode Anode OUTPUT Earth Ground 777 Figure 2
19. instrument is to be shipped to ILX Lightwave for repair or service be sure to 1 Obtain a Return Authorization number RA from ILX Customer Service 2 Attach a tag to the instrument identifying the owner and indicating the required service or repair Include the instrument serial number from the rear panel of the instrument 3 Attach the anti static protective caps that were shipped with the instrument and place the instrument in a protective anti static bag 4 Place the instrument in the original packing container with at least inches 7 5 cm of compressible packaging material Shipping damage is not covered by this warranty 5 Secure the packing box with fiber reinforced strapping tape or metal bands 6 Send the instrument transportation pre paid to ILX Lightwave Clearly write the return authorization number on the outside of the box and on the shipping paperwork ILX Lightwave recommends you insure the shipment If the original shipping container is not available place your instrument container with at least 3 inches 7 5 cm of compressible packaging material on all sides Repairs are made and the instrument returned transportation pre paid Repairs are warranted for the remainder of the original warranty or for 90 days whichever is greater Safety and Warranty Information TT Claims for Shipping Damage When you receive the instrument inspect it immediately for any damage or shortages on the pa
20. k Chassis Ground 4 5 Laser Cathode 6 PD Cathode 7 PD Anode 8 9 Laser Anode Figure 2 3 D connector J105 Pinout 8 m LDX 3412 Lightwave OPERATION Installation Output Connectors Output current is available from the 9 pin D sub connector J105 Pins 4 and 5 are the negative output and pins 8 and 9 are the positive output current connections These pins are jumpered to provide greater contact area for the output connections This is done to reduce the risk of an open output connection due to loose connector Thus the output is made safer for laser diodes Note Whenever external connections are made to the output at pins 4 and 5 and 8 and 9 These connector leads must be jumpered as shown above to ensure the greatest laser diode safety Chassis GND Connector The output current terminals are floating with respect to chassis ground A chassis ground GND connector bare metal is available for the user s convenience See Section 2 5 4 Laser Diode Connections and Shielding Photodiode Feedback PD GAIN Adjustment Photodiode feedback gain may be adjusted by the user via the COARSE and FINE controls on the rear panel of the LDX 3412 When the CONST P mode is selected the user may adjust the feedback gain for proper testing of a laser diode Turning the COARSE and FINE controls counter clockwise CCW will increase the feedback gain and decrease the output current See Figure 2 4 for setting the photo
21. riate troubleshooting actions are given We recommend that the user start at the beginning of this guide Read the symptom descriptions and follow the steps for the corrective actions which apply If you encounter problems which are beyond the scope of this troubleshooting guide contact ILX Lightwave at the number listed at the front of Lightwave LDX 3412 15 16 LDX 3412 TROUBLESHOOTING Troubleshooting this manual Our Service Engineers will be glad to answer any questions concerning this or any other ILX Lightwave product Table 3 1 Troubleshooting Symptoms and Actions SYMPTOM CORRECTIVE ACTIONS LDX 3412 will not power up Check AC Power line voltage and power cord connection LDX 3412 powers up but there is no current OUTPUT Check the MODE switch Output will only be on while in CONST I or CONST P modes Check the interlock feature If interlock is enabled there must be a short between pins 1 and 2 of J105 to have output Check the OUTPUT switch The LED should be lit Check the OPEN CKTindicator If it is lit there is an open in the output circuit Output current at limit cannot be lowered Check the current output control knob Set it fully counter clockwise CCW for minimum output If CONST P mode is used check the feedback gain setting Section 2 3 11 Try turning the feedback GAIN controls down CCW If CONST P mode is used check the feedback connections Try reversin
22. t switch allows the user to select between the three modes of operation by turning the MODE knob to the desired mode CONST P selects constant power mode for photodiode feedback control CONST I selects constant current mode for normal operation LIMIT DISPLAY selects a display mode in which the output is turned off and the current LIMIT is displayed on the LED display When the MODE select switch is turned between modes the output is turned off Current LIMIT Adjustment The current LIMIT knob allows the user to set the upper limit on output current The user may adjust the output current from zero LIMIT knob fully counter clockwise CCW to 200 mA LIMIT knob fully clockwise CW This LIMIT knob is recessed to prevent accidental readjustment of the output current during operation Lightwave 03_11 OPERATION Installation Under all modes of operation the output current is unconditionally limited to the value set by the LIMIT adjustment Output Current Adjustment The output current adjustment knob is located in the top right hand corner of the front panel Turning this knob clockwise CW will increase the output current The output current will be displayed on the LED display during CONST P or CONST I operation OUTPUT Off On Switch The OUTPUT off on switch is located in the lower right hand corner of the front panel This switch has a toggling action which turns the output current of the LDX 3412 on and off When t
23. ur instrument Safety and Warranty Information vii TT container with at least 3 inches 7 5cm of compressible packaging material on all sides We look forward to serving you even better in the future Safety and Warranty Information um Lx Lightwave CHAPTER 1 GENERAL INFORMATION 5 B El a la a El El mH El HE E LI El E This manual contains operation and maintenance information for the LDX 3412 Precision Current Source Appendix contains brief troubleshooting guide Product Overview The LDX 3412 is an easy to operate precision current source It is optimized for driving laser diodes and LEDs with an output range of 0 to 200 mA with compliance voltage of gt 6 volts Multiple built in protection features ensure that the supply output is transient free and bounded under all conditions There are three modes of operation for the LDX 3412 1 Constant Power which allows photodiode feedback to control the output current 2 Constant Current in which feedback from the laser is used to control the output current and 3 Limit Display in which the current limit is displayed while the output current is off Features of the LDX 3412 include Intuitive front panel layout Fully independent precision current limit control Slow turn on circuit for laser diode protection Safe OUTPUT off on switch Double shielded transformers for low noise Photodiode feedback capability
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