Ascent Communication Technology

100G QSFP28 LX4 2km

The 100GBASE-LX4 module is a versatile and high-performance optical transceiver designed to support link lengths of up to 2 km over single-mode fiber (SMF) and up to 100 meters on OM3 multimode fiber (MMF) using a Duplex LC connector. It is designed for a wide range of applications, including data centers and enterprise networking environments where reliable high-speed data transmission is essential. Its ability to operate across both SMF and MMF provides flexibility for network architects, enabling seamless integration into existing infrastructure while meeting the demands of 100G Ethernet applications. This transceiver is a fully integrated 4 x 25.78 Gbps optical module, utilizing advanced optical components to ensure exceptional performance. It incorporates cooled distributed feedback laser diodes (DFB LDs) operating at wavelengths of 1270 nm, 1290 nm, 1310 nm, and 1330 nm. These are paired with high-performance driver integrated circuits (ICs), PIN photodiodes, and clock and data recovery (CDR) ICs that support 25 Gbps electrical interfaces. This combination ensures precise and efficient optical signal transmission, making it well-suited for high-density network environments and demanding data rates. Additionally, the 100GBASE-LX4 module features built-in digital diagnostics monitoring (DDM), which provides access to real-time operating parameters such as temperature, laser bias current, and transmitted/received optical power. This monitoring capability enhances network reliability by enabling proactive maintenance and reducing downtime.

· QSFP28 MSA compliant

· Supports 103.1 Gb/s aggregate bit rate

· 4x25Gb/s electrical interface

· Up to 2km on SMF and 100m on MMF(OM3)

· Hot-pluggable QSFP28 footprint

· LC duplex connector

· Maximum power consumption 3.5 Watts

· Single 3.3V power supply

· Support Digital Diagnostic Monitor interface

· Case operating temperature: 0°C to +70°C

· RoHS compliant

Absolute Maximum Rating
It has to be noted that the operation in excess of any individual absolute maximum ratings might cause permanent damage to this module.

Parameter	Symbol	Min.	Max.	Unit	Note
Maximum Supply Voltage	V_cc	0	3.6	V
Storage Temperature	Ts	-40	85	°C
Operating Case Temperature	T_case	-5	75	°C
Relative Humidity	R_H	5	85	%
Damage Threshold,per Lane	P_dam	3.6		dBm

Recommended Operating Conditions

Parameter	Symbol	Min.	Typ.	Max.	Unit	Note
Operating Case Temperature	T_case	0		70	°C
Supply Voltage	V_cc	3.135	3.3	3.465	V
Relative Humidity	R_H	5		85	%
Power Consumption	P_D			3.5	W
Data Rate (Optical)	DR_O		4*25.78125		Gbps
Data Rate (Electrical)	DR_E		4*25.78125		Gbps
Operating Link Distance	L_D		SMF:2 MMF:0.1@OM3		km

Optical Characteristics
100GBASE-LX4 Operation（EOL, TOP = 0 to 70 °C,V_cc = 3.135 to 3.465 V）

Parameter	Symbol	Min.	Typ.	Max.	Unit	Note
Transmitter
Signaling Speed per Lane	BR	25.78125 ± 100 ppm			Gbps
Lane Wavelength	λ0	1264.5	1271	1277.5	nm
	λ1	1284.5	1291	1297.5	nm
	λ2	1304.5	1311	1317.5	nm
	λ3	1324.5	1331	1337.5	nm
Side-Mode Suppression Ratio	SMSR	30			dB
Total Average Launch Power for SMF	P_total			8.5	dBm
Total Average Launch Power for MMF	P_total	-2.5		9.5	dBm
Average Launch Power per Lane for SMF	P_out	-6.5		2.5	dBm
Average Launch Power per Lane for MMF		-5.0		3.5	dBm
Transmit OMA per Lane for SMF	TxOMA	-4.0		2.5	dBm
Transmit OMA per Lane for MMF		-4.0		3.5	dBm
Launch Power OFF per Lane	POff			-30	dBm
Transmitter and Dispersion Penalty (TDP), each Lane	TDP			3	dB
Extinction Ratio (ER)	ER	3.5			dB
RIN20 OMA	R_IN			-128	dB/Hz
Transmitter Eye Mask Definition {X1,X2, X3,Y1, Y2, Y3}	{0.31, 0.40, 0.45, 0.34, 0.38, 0.4}					1
Mask margin		15			%	1
Receiver
Signaling Rate, Each Lane	BR	10.3125 ± 100 ppm			Gb/s
Receive Wavelength	λ0	1264.5	1271	1277.5	nm
	λ1	1284.5	1291	1297.5	nm
	λ2	1304.5	1311	1317.5	nm
	λ3	1324.5	1331	1337.5	nm
Damage Threshold, each Lane	P_max			3.5	dBm
Average Receive Power per Lane for SMF		-11.5		2.5	dBm
Average Receive Power per Lane for MMF		-8.6		3.5	dBm
Rx Sensitivity (OMA) per Lane for SMF	R_SEN			-8.6	dBm
Rx Sensitivity (OMA) per Lane for MMF				-8.6	dBm
Receiver Reflectance	Rfl			-26	dB
LOS Assert	LOSA	-30			dBm
LOS De-Assert	LOSD			-12.5	dBm
LOS Hysteresis		0.5		6	dB

Note: Hit ratio 5 x 10⁻⁵.

Electrical Interface Characteristics
100GBASE-LX4 Operation (EOL, TOP = 0 to 70 °C ,V_cc = 3.135 to 3.465 V）

Parameter	Symbol	Min	Typ	Max	Unit	Note
Power Consumption				3.5	W
Supply Current	I_cc			1	A
Transmitter
Data Rate, each Lane			25.78125		Gbps
Differential Voltage Pk-Pk	V_pp	300		850	mV
Input Differential Impedance	R_in		100		Ohm	1
Differential Termination Resistance Mismatch				10	%
Receiver
Data Rate, each Lane			25.78125		Gbps
Output Differential Impedance	R_out		100		Ohm	1
Differential Termination Resistance Mismatch				10	%
Differential Output Voltage	V_out, pp	260		850	mV	2

Notes:

1. Connected directly to TX data input pins. AC coupled there after.

2. Into 100Ω differential termination.

Digital Diagnostic Monitoring Functions
QSFP28-100G-LX02 support the I2C-based Diagnostic Monitoring Interface (DMI) defined in document SFF-8636. The host can access real-time performance of transmitter and receiver optical power, temperature, supply voltage and bias current.