OEM Laser Diode Driver: Constant Power

Overview
Pin Diagrams
Smart Pack
Feedback
Selection Guide

Item#	LD1100	LD1101	EK1101^a	EK1102^b
Output Current	0 - 250 mA
Supported Laser Pin Configurations	A, B, D, & F	C, D, & F	A	B
Recommended for LEDs^b	No	No	Yes	Yes
Output Control	12-Turn Power Adjustment (On-Board)
Output Stability	1.5%
Output Noise	5 μA RMS
Feedback Gain	Adjustable
Monitor Current Range	5 μA to 5 mA
Operating Voltage	8 to 12 VDC
Quiescent Current	9 mA
Dimensions	1" x 1.5" 12-Pin SIP Package		See Drawing
ESD Protection	100 ms Slow Start
Max Output Voltage	~6.5 V (with a 12 V Power Supply)

The EK1101 and EK1102 can be used with pin configurations D and F if the included socket is replaced with a suitable 4-pin socket. The socket must be wired correctly in order to support the pin style.
With monitor photodiode.

Laser Diode Drivers
The LD1100 and LD1101 Laser Diode Drivers are constant-power laser driver modules that support common laser anode and common laser cathode pin configurations. They feature an on-board 12-turn trim pot for continuous laser power output adjustment, pin-programmable feedback gain, ON/OFF control input, and a current monitor output for observing the laser drive current. With dimensions of only 1" x 1.5", they are compact and can be embedded into custom designs. The compliance voltage, which is the maximum output voltage, is ~6.5 V for the LD1100 and LD1101 when using a 12 V power supply. All input and output signals are provided on a 12-pin SIP connector, which allows simple integration into a printed circuit design.

The LD1100 and LD1101 can drive lasers up to 250 mA in a constant-power mode. Either uses the internal monitor photodiode for a feedback signal into a proportional-integral feedback loop to stabilize the output power to within 1.5%. To accommodate a wide range of laser diodes, the feedback gain can be set by using jumpers between any combination of the five gain setting resistor pins to the power supply common. This allows lasers with monitor currents over a range from 5 μA to 5 mA to be used with a single driver.

Evaluation Kits
The EK1100 Series Evaluation Kit is an LD1100 Laser Driver soldered to a PCB that features an on/off switch and a dip switch bank for controlling the gain on the feedback signal. A 3-pin laser socket cable (S8060) is also soldered onto the PCB board (this determines the pin configuration supported by the kit). In addition to driving lasers, the EK1101 and EK1102 are also suggested for operating LEDs that contain a monitor photodiode with an A or B style pin configuration, respectively.

Power Supply Options
A power supply cable for 9 V batteries is included but not attached. Alternatively, our LDS9 power supply can be used if the phono connector is removed and the bare wires are exposed.

Note on Cosmetic Appearance
The physical appearance of the board-level components on the LD1100 and LD1101 drivers may vary from that pictured above. Regardless of their appearance, the drivers conform to the electrical and operational specifications described here.

Supported Pin Configurations

LD1100 Pin Configurations

Pin	Signal	Description
1	+V	Circuit Power, 8 to 12 VDC, 9 mA + Laser Drive Current NOTE: Internally tied to Laser Diode Anode, the laser anode must be isolated from the power supply COM
2	COM	Circuit Ground
3	V_REF	Internal 2.5 V reference
4	PDA	Photodiode Anode
5	LDA	Laser Diode Anode (Internally Tied to +V (Pin 1))
6	LDC	Laser Diode Cathode
7	RA	When Tied to Common, Puts 100 kΩ in Parallel with 249 kΩ Internal Gain Resistor
8	RB	When Tied to Common, Puts 33.2 kΩ in Parallel with 249 kΩ Internal Gain Resistor
9	RC	When Tied to Common, Puts 10 kΩ in Parallel with 249 kΩ Internal Gain Resistor
10	RD	When Tied to Common, Puts 3.32 kΩ in parallel with 249 kΩ Internal Gain Resistor
11	RE	When Tied to Common, Puts 1 kΩ in Parallel with 249 kΩ Internal Gain Resistor
12	I_LD	Laser Diode Current Monitor (10 mV/mA)

LD1101 Pin Configurations

Pin	Signal	Description
1	+V	Circuit Power, 8 to 12 VDC, 9 mA + Laser Drive Current NOTE: Internally tied to Laser Diode Anode. The laser anode must be isolated from the power supply COM.
2	COM	Circuit Ground
3	V_REF	Internal 2.5 V reference
4	PDC	Photodiode Cathode
5	LDA	Laser Diode Anode (Internally Tied to +V (Pin 1))
6	LDC	Laser Diode Cathode
7	RA	When Tied to Pin 6, Puts 5 kΩ in parallel with 12.4 kΩ Internal Gain Resistor
8	RB	When Tied to Pin 6, Puts 1.5 kΩ in parallel with 12.4 kΩ Internal Gain Resistor
9	RC	When Tied to Pin 6, Puts 499 Ω in parallel with 12.4 kΩ Internal Gain Resistor
10	RD	When Tied to Pin 6, Puts 160 Ω in parallel with 12.4 kΩ Internal Gain Resistor
11	RE	When Tied to Pin 6, Puts 33 Ω in parallel with 12.4 kΩ Internal Gain Resistor
12	I_LD	Laser Diode Current Monitor (10 mV/mA)

EK1101

Laser Anode - Photodiode Cathode Common

Pin Style A

Laser Pin	J1 Pin (on Evaluation Board)	Wire Color
PDA	PD_A	Green
LDA/PDC	LD_A	Red
LDC	LD_C	Yellow

EK1102

Laser Cathode - Photodiode Cathode Common

Pin Style B

Laser Pin	J1 Pin (on Evaluation Board)	Wire Color
PDA	PD_A	Green
LDA	LD_A	Yellow
LDC/PDC	LD_C	Red

EK110x Laser Socket Wire Harness

Laser Socket

Click to Enlarge
EK1101 Packaging

Smart Pack

Reduce Weight of Packaging
Increase Usage of Recyclable Materials
Improve Packing Integrity
Decrease Shipping Costs

Thorlabs' Smart Pack Initiative is aimed at minimizing waste while providing adequate protection for our products. By eliminating any unnecessary packaging, implementing design changes, and utilizing eco-friendly materials, this initiative seeks to reduce the environmental impact of our product packaging.

The updated EK1101 and EK1102 packaging primarily consists of recycled paper and cardboard and weighs 19.70% less than the original packaging. This weight change results in a 3.79 kg reduction in travel-based CO₂ emissions per year, based on typical product sales.

As we move through our product line, we will indicate re-engineered, eco-friendly packaging with our Smart Pack logo, which can be seen above.

Posted Comments:

Yu-Xuan Wu (posted 2021-01-27 18:01:26.757)

Hello! I found that our 405 nm laser(DL-5146-101S) which is driven by EK1102 encountered a problem. The power of the laser was consistently rising(sometimes falling). Would it be helpful using the temperature controller? Or do you have any other suggestion?

YLohia (posted 2021-02-16 02:18:15.0)

Hello, thank you for contacting Thorlabs. We had reached out to you with a few troubleshooting questions, but we didn't hear back. Over what time scale does this fluctuation occur? How are you measuring the power? Are there any other optical components between the laser and your power sensor? Have you checked for an eliminated back-reflections into the laser cavity? Are you able to monitor the laser current and the monitor photodiode current? Do they fluctuate the same amount as your laser power?

Justin Molloy (posted 2019-09-12 09:54:30.837)

I have made a simple "hack" to enable computer control of power using this driver. If you would like to see the small modification required and/or would like the Arduino code for manual rotary encoder power control and ability to control via RS232 please feel free to contact me. There would be NO Warranty at all and I accept no liability for any faults in design/software etc - i.e. use entirely at your own risk!

YLohia (posted 2019-09-12 12:59:25.0)

Hello Justin, thank you for contacting Thorlabs and offering us this code. I have added this to our internal knowledge base with due credit to you. We believe the rest of our customer base will really appreciate this as well. This code can now be requested by our other customers by emailing techsupport@thorlabs.com.

mitch (posted 2016-08-11 03:48:19.71)

Hi, is it possible to use the LD1100 to bias a VCSEL?

jlow (posted 2016-08-15 10:31:03.0)

Response from Jeremy at Thorlabs: This board is not recommended for VCSEL by itself. You could use it in conjunction with our T1G bias-T PCB for pulsed operation. We also have VCSEL drivers at https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=1377.

x.attendu (posted 2016-06-27 12:53:28.85)

Hi, I would like to know if it would be possible to drive multiple laser diodes simultaneously with this product. The idea would be to connect 3 different laser diodes in parallel each with a laser diode bias tee to modulate their currents separately. Would this work or am I going to fry the driver ? Thank you for your time.

jjurado (posted 2011-04-06 16:59:00.0)

Response from Javier at Thorlabs to li.li: Thank you for contacting us with your request. The change in driving current is a result of heating of the laser diode. The EK1102 is a constant power laser diode driver, and, as the diode heats up and loses efficiency, the driver injects more current in order to keep the power output constant. If the diode has a relatively high operating current, and if the experiment requires the diode to be turned on for extended periods of time, it is recommended to provide temperature control in order to prevent potential damage. If passive heat dissipation by a heatsink is not enough, then it would be recommended to use a thermoelectric cooler. You can find our offerings through the following link: http://www.thorlabs.com/NewGroupPage9.cfm?ObjectGroup_ID=305 I will contact you directly in case you have additional questions.

li.li (posted 2011-04-06 13:43:11.0)

The LD driving current is increasing with time. Is it caused by the temperature of laser diode? Shall I set a maximum driving current for the laser diode through the EK1102, otherwise Im affraid the diode laser will be damaged. Probably I need a Peltier cooler, could you please recommend me some products for the laser diode cooler? Thank you for your time.

Tyler (posted 2009-01-08 16:44:18.0)

A response from Tyler at Thorlabs to melsscal: This modification can be made. I will have a member of our technical support department contact you. They can create a quote for the modified part.

melsscal (posted 2009-01-08 06:45:59.0)

Can you arrange to make a connector for connecting the LDS2 to EK1101 ? Regards A.K.Bose MELSS KOLKATA/INDIA melsscal@melss.com

Laser Diode Controller Selection Guide

The tables below are designed to give a quick overview of the key specifications for our laser diode controllers and dual diode/temperature controllers. For more details and specifications, or to order a specific item, click on the appropriate item number below.

Current Controllers
Item #	Drive Current	Compliance Voltage	Constant Current	Constant Power	Modulation	Package
LDC200CV	20 mA	6 V			External	Benchtop
VLDC002	25 mA	5 V		-	Int/Ext	OEM
LDC201CU	100 mA	5 V			External	Benchtop
LD2000R	100 mA	3.5 V	-		External	OEM
EK2000	100 mA	3.5 V	-		External	OEM
LDC202C	200 mA	10 V			External	Benchtop
KLD101	230 mA	≤10 V			External	K-Cube™
IP250-BV	250 mA	8 V^a			External	OEM
LD1100	250 mA	6.5 V^a	-		--	OEM
LD1101	250 mA	6.5 V^a	-		--	OEM
EK1101	250 mA	6.5 V^a	-		--	OEM
EK1102	250 mA	6.5 V^a	-		--	OEM
LD1255R	250 mA	3.3 V		-	External	OEM
LDC205C	500 mA	10 V			External	Benchtop
IP500	500 mA	3 V			External	OEM
LDC210C	1 A	10 V			External	Benchtop
LDC220C	2 A	4 V			External	Benchtop
LD3000R	2.5 A	--		-	External	OEM
LDC240C	4 A	5 V			External	Benchtop
LDC4005	5 A	12 V			Int/Ext	Benchtop
LDC4020	20 A	11 V			Int/Ext	Benchtop

When using a 12 V power supply.

Dual Temperature and Current Controllers
Item #	Drive Current	Compliance Voltage	TEC Power (Max)	Constant Current	Constant Power	Modulation	Package
VITC002	25 mA	5 V	>2 W		-	Int/Ext	OEM
ITC102	200 mA	>4 V	12 W			Ext	OEM
ITC110	1 A	>4 V	12 W			Ext	OEM
ITC4001	1 A	11 V	>96 W			Int/Ext	Benchtop
CLD1010LP^a	1.0 A	>8 V	>14.1 W			Ext	Benchtop
CLD1011LP^b	1.0 A	>8 V	>14.1 W			Ext	Benchtop
CLD1015^c	1.5 A	>4 V	>14.1 W			Ext	Benchtop
ITC4002QCL^d	2 A	17 V	>225 W			Int/Ext	Benchtop
ITC133	3 A	>4 V	18 W			Ext	OEM
ITC4005	5 A	12 V	>225 W			Int/Ext	Benchtop
ITC4005QCL^d	5 A	20 V	>225 W			Int/Ext	Benchtop
ITC4020	20 A	11 V	>225 W			Int/Ext	Benchtop

Combined controller and mount for pigtailed laser diodes in TO can packages with A, D, E, or G pin codes only.
Combined controller and mount for pigtailed laser diodes in TO can packages with B, C, or H pin codes only.
Combined controller and mount for laser diodes in butterfly packages only.
Enhanced compliance voltage for QCL operation.

We also offer a variety of OEM and rack-mounted laser diode current & temperature controllers (OEM Modules, PRO8 Current Control Rack Modules, and PRO8 Current and Temperature Control Rack Modules).

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