Our Go To for Cisco switches
We have bought these for years. They are our go to SFP for Cisco switches. Use both the 1GB and 10GB link versions. They have been rock solid for us in our network, at a great price, and fast ship when ordered
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FluxLight's GLC-LH-SM-FL is a Cisco® compatible 1000Base SFP Optical Transceiver and is factory pre-programmed with all the necessary configuration data for seamless network integration. Our transceivers perform identically to Cisco® original transceivers and are 100% compatible with other OEM and third party transceivers. The GLC-LH-SM-FL Cisco SFP transceiver is 100% MSA (Multi-Source Agreement) compliant. All FluxLight's transceivers are tested for 100% functionality and guaranteed compatible for outstanding network performance.
The operation in excess of any absolute maximum ratings might cause permanent damage to this module.
| Parameter | Symbol | Min | Max | Unit |
|---|---|---|---|---|
| Storage Temperature | TS | -40 | 85 | °C |
| Operating Case Temperature | TOP | 0 | 70 | °C |
| Power Supply Voltage | VCC | -0.3 | 3.6 | V |
| Relative Humidity (non-condensation) | RH | 5 | 85 | % |
| Parameter | Symbol | Min | Typical | Max | Unit |
|---|---|---|---|---|---|
| Operating Case Temperature | TOP | 0 | 70 | °C | |
| Power Supply Voltage | VCC | 3.135 | 3.3 | 3.465 | V |
| Power Consumption | 1 | W | |||
| Data Rate | DR | 1.25 | Gbps | ||
| Link Distance with SMF | D | 10 | km |
| Parameter | Symbol | Min | Typical | Max | Unit |
|---|---|---|---|---|---|
| Transmitter | |||||
| Center Wavelength | λC | 1260 | 1310 | 1360 | nm |
| RMS Spectral Width | λrms | 3.5 | nm | ||
| Average Launch Power | PAVG | -9 | -3 | dBm | |
| Rise/Fall Time | Tr/Tf | 260 | ps | ||
| Extinction Ratio | ER | 9 | dB | ||
| Transmitter Eye Mask | Compliant with IEEE 802.3 standard | ||||
| Receiver | |||||
| Center Wavelength | λC | 1260 | 1580 | nm | |
| Damage Threshold | THd | -1 | dBm | ||
| Receiver Sensitivity | SEN | -23 | dBm | ||
| LOS Assert | LOSA | -45 | dBm | ||
| LOS De-Assert | LOSD | -24 | dBm | ||
| LOS Hysteresis | LOSH | 1 | dB | ||
Notes:

The following digital diagnostic characteristics are defined over the normal operating conditions unless otherwise specified.
| Parameter | Symbol | Min | Max | Unit |
|---|---|---|---|---|
| Temperature monitor absolute error | DMI_Temp | -5 | 5 | °C |
| Supply voltage monitor absolute error | DMI_VCC | -0.1 | 0.1 | V |
| Channel RX power monitor absolute error | DMI_RX_Ch | -3 | 3 | dB |
| Channel Bias current monitor | DMI_Ibias_Ch | -10% | 10% | mA |
| Channel TX power monitor absolute error | DMI_TX_Ch | -3 | 3 | dB |
Units: mm


| Pin | Signal Name | Description | Plug Seq. | Notes |
|---|---|---|---|---|
| 1 | VeeT | Transmitter Ground | 1 | 1 |
| 2 | TX FAULT | Transmitter Fault Indication | 3 | |
| 3 | TX DISABLE | Transmitter Disable | 3 | 2 |
| 4 | SDA | SDA Serial Data Signal | 3 | 3 |
| 5 | SCL | SCL Serial Clock Signal | 3 | 3 |
| 6 | MOD_ABS | Module Absent. Grounded within the module | 3 | 3 |
| 7 | RS0 | Not Connected | 3 | 4 |
| 8 | LOS | Loss of Signal | 3 | 5 |
| 9 | RS1 | Not Connected | 3 | 4 |
| 10 | VeeR | Receiver ground | 1 | 1 |
| 11 | VeeR | Receiver ground | 1 | 1 |
| 12 | RD- | Inv. Received Data Out | 3 | 6 |
| 13 | RD+ | Received Data Out | 3 | 6 |
| 14 | VeeR | Receiver ground | 1 | 1 |
| 15 | VCCR | Receiver Power Supply | 2 | |
| 16 | VCCT | Transmitter Power Supply | 2 | |
| 17 | VeeT | Transmitter Ground | 1 | |
| 18 | TD+ | Transmit Data In | 3 | 6 |
| 19 | TD- | Inv. Transmit Data In | 3 | 6 |
| 20 | VeeT | Transmitter Ground | 1 |
Notes:
This transceiver is specified as ESD threshold 1kV for high-speed data pins and 2kV for all other electrical input pins, tested per MIL-STD-883, Method 3015.4 /JESD22-A114-A (HBM). However, normal ESD precautions are still required during the handling of this module. This transceiver is shipped in ESD protective packaging. It should be removed from the packaging and handled only in an ESD protected environment.
This is a Class 1 Laser Product according to IEC 60825-1:2007. This product complies with 21 CFR 1040.10 and 1040.11 except for deviations pursuant to Laser Notice No. 50, dated (June 24, 2007).
The following is a list of Finisar Corporation patents Fluxlight has licensed. This licensure recognizes and compensates Finisar for their intellectual property. The GLC-LH-SM-FL, like all Fluxlight optical transceivers, is covered by this license agreement. Therefore, Fluxlight customers can rest assured that all products purchased are fully licensed, and our customers are under no potential liability that may ensue from the use of unlicensed optical transceiver products.
U.S. Patent Numbers: 7,184,668 (System and method of protecting eye safety during operation of a fiber optic transceiver), 7,079,775 (Integrated memory mapped controller circuit for fiber optics transceiver), 6,957,021 (Optical transceiver with memory mapped locations), 7,058,310 (System and method for protecting eye safety during operation of a fiber optic transceiver), 6,952,531 (System and method for protecting eye safety during operation of a fiber optic transceiver), 7,162,160 (System and method for protecting eye safety during operation of a fiber optic transceiver), 7,050,720 (Integrated memory mapped controller circuit for fiber optics transceiver)
Original Equipment Manufacturer (OEM) names may be registered trademarks of the respective OEM, and the OEM has neither authorized nor sponsored the use of its trademark or trade name. All OEM names are used for cross reference/comparative purposes only.
This part is covered by our Limited Lifetime Warranty, a 10-year serviceable lifetime, and our 30-Day Money-Back Guarantee. Read the full warranty and return terms.
We have bought these for years. They are our go to SFP for Cisco switches. Use both the 1GB and 10GB link versions. They have been rock solid for us in our network, at a great price, and fast ship when ordered
These work great! Shipping is fast and great service if you need them.
Our go to place for lasers. Fast, great service, stand behind their products! #1 all the way.....
Nearly 16 years into this career... I've had dozens of failed vendor-branded transceivers fail vs 3 fluxlight. In spite of vendors claiming "increase QA controls", Fluxlight continues to inspire confidence through integrity. Cisco gives one year warranty for 20x the price. Flux gives lifetime warranty. Give fluxlight a chance and you won't be disappointed.
Flux Light is a great company. Their products are awesome, and their Sales and Customer Service Teams are very personable and adept.
They work well at a great price.
We use these SFPs exclusively on all our installations. The reliability is critical for us because most of our installs are located in remote areas and we can't afford failure. We have used this SFP (and others from FluxLight) with zero compatibility issues or failures.
We have used various type of SFPs from FluxLight with zero problems with compatibility. I would highly recommend them.
I have used these on multiple switches and firewalls without issue.
I have used about a dozen of these just recently. They fit well and perform well.
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