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6

PLD10000/PLD12500 LASER DIODE DRIVER

SAFETY INFORMATION

SAFE OPERATING AREA — DO NOT EXCEED 
INTERNAL POWER DISSIPATION LIMITS

Before attempting to operate the PLD driver, it is imperative 

that you first determine that the unit will operate within the 

Safe Operating Area

 (SOA). Operating outside of the SOA 

may damage the PLD and the laser. Operating outside of 

the SOA will void the warranty.

To determine if the PLD driver is suitable for your application 

and if it will be operating in the safe range, consult the online 

instructions for calculating the Safe Operating Area: 

https://www.teamwavelength.com/support/design-tools/soa-ld-calculator/

https://www.teamwavelength.com/support/design-tools/soa-ld-calculator/

SOA charts are included in this datasheet for quick reference 

(

page 17

), but we recommend you use the online tools 

instead.

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If you have any questions about the Safe Operating Area 

calculator call the factory for free and prompt technical 

assistance.

THEORY OF OPERATION

The PLD10000 and PLD12500 drivers are controlled 

linear-mode current sources: they deliver the current 

commanded by the setpoint. The current source continually 

monitors the actual output current, compares it to the 

setpoint, and adjusts the current if there is a difference 

between the two signals.

It may be useful to remember that you do not directly set the 

drive current setpoint; instead, you adjust a voltage signal 

that represents the output current. The voltage and output 

current are related by a transfer function that varies by driver 

model number.

The setpoint voltage is adjusted with the onboard trimpot or 

by an external input that sums with the onboard setpoint. 

The adjustable current limit is set using an onboard trimpot.

As current is driven through the load, there is a voltage drop 

across the load because of the impedance. As the current 

increases, the voltage drop may increase to the point that it 

reaches the Compliance Voltage limit of the current source. 

Once that occurs the current source is no longer able to 

increase the current driven to the load even if you increase 

the setpoint. 

The PLD driver includes features that help protect your 

laser and make the driver more versatile in a wide array of 

applications:

•  The user-adjustable latching current limit protects the 

laser from over-current situations by switching off the 

output when a limit condition is detected. Toggling the 

Enable resets the current limit circuit.

•  Output current switches on after approximately 1.5 

seconds from the time the Enable signal is applied.

•  Output slow-start ramps the current to setpoint over 

250 msec.

Summary of Contents for PLD10000

Page 1: ...witches off the output if the current limit is reached a slow start circuit ramps the output current and a mechanical shorting relay protects the laser from ESD events while the output is switched off...

Page 2: ...e Cathode Photodiode Anode Common MODE P L I H OUT LIM I PLD10000 Laser Diode Driver PD RNG 5V Analog In P Monitor I Monitor Common Lim I Mon Lim I Stat LD Enable PD Aux Aux V GND LD Anode LD Supply L...

Page 3: ...refer to Figure 4 When using the test load the actual drive current can be determined by measuring the voltage drop across the resistor Do not place an ammeter in series with the load circuit 1 5 2 5...

Page 4: ...by PD feedback range setting refer to Table 2 Range 0 to 2 5 V Impedance 1 k 18 I Monitor Laser Diode Output Current Monitor Transfer function varies by model refer to Table 2 Range 0 to 2 5 V Impeda...

Page 5: ...ge Threshold VIN 0 5 or VIN 0 5 V above Supply Voltage on Pin 15 V Input Pin Impedance 1 M Bandwidth 3 dB5 90 70 kHz Depth of Modulation at 60 kHz6 90 Rise Time 7 7 sec Fall Time 8 8 sec TIMING CHARAC...

Page 6: ...by the setpoint The current source continually monitors the actual output current compares it to the setpoint and adjusts the current if there is a difference between the two signals It may be useful...

Page 7: ...LD10000 5 VDC power supply rated for 250 mA Power supply rated for 1 1 times the maximum laser diode drive current and 2 5 V greater than the compliance voltage of the laser NOTE For dual supply opera...

Page 8: ...must be removed when using the PLD12500 The factory default configuration is with the jumper installed GND VCC GND Connector AUX VCC VCC NC PD ANODE PD CATHODE ANALOG INPUT I MONITOR COMMON MON LIM I...

Page 9: ...D Enable 10 11 12 5 V GND Internally Shorted 16 19 18 21 17 20 Analog Input LIM I Monitor LIM I Status PD Anode 3 Common Low Current PD LD OR Closed Output Enabled Open Output Disabled 10 F 5V 0 1 F 1...

Page 10: ...le 10 11 12 5 V GND Internally Shorted 16 19 18 21 17 20 Analog Input LIM I Monitor LIM I Status PD Cathode 2 Common Low Current PD LD OR Closed Output Enabled Open Output Disabled 10 F 5V 0 1 F 8 to...

Page 11: ...be damaged or destroyed CALCULATE THE MONITOR VOLTAGES Refer to the datasheet for your laser to determine the maximum forward current and calculate the LIM I Monitor voltage using this equation and t...

Page 12: ...The Analog Input voltage signal on pin 16 sums with the onboard trimpot setpoint This configuration allows the driver to be configured so that the laser current or power modulates around a DC setpoin...

Page 13: ...he external resistor 3 19 PD Range Switch 554 5 k PD Range L A A V PD Range H 2 5 V 10 6 R 500 Range A A V 6 R 500 10 Transfer Function 2 5 V 10 6 R 5 k Range 6 R 5 k 10 Transfer Function R 5 k R 5000...

Page 14: ...y grounded If the PLD driver is used with a Wavelength Electronics temperature controller you may need to use two separate power supplies that float independently of each other If the laser anode is c...

Page 15: ...5 Output Timing Revision B MODEL TURN ON TIME TURN OFF TIME SLOWSTART DELAY PLD10000 5 3 sec 9 5 sec 1 5 sec PLD12500 5 sec 8 sec 1 5 sec MONITOR CALIBRATION CIRCUIT A small offset may be present whe...

Page 16: ...DRIVER OUTPUT ON OFF AND CURRENT LIMIT TIMING Figure 18 through Figure 20 illustrate the the output turn on delay slowstart turn on off time and current limit response Figure 18 Output Turn On Delay...

Page 17: ...late the voltage drop across the controller VDROP VS VMAX VS is the power supply voltage Mark VDROP on the X axis and extend a line upward Mark IMAX on the Y axis and extend a line to the right until...

Page 18: ...ations table on page 5 If the driver is compliance limited VLD Anode pins 7 8 9 may need to be increased Verify that the PLD will be operating within the Safe Operating Area if the supply voltage is i...

Page 19: ...2 450 62 23 3 050 77 47 2 75 69 85 0 30 7 62 3 35 85 09 3 20 81 28 0 40 10 16 0 15 3 81 1 03 26 15 1 100 27 94 Figure 23 PL10000 PLD12500 Mechanical Dimensions 4 000 0 250 4 500 5 000 0 250 5 500 0 1...

Page 20: ...s document is subject to change without notice Wavelength will not be liable for errors contained herein or for incidental or consequential damages in connection with the furnishing performance or use...

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