Ascent Communication Technology

2.5G SFP 1310 nm 2 km

Ascent’s 2.5 Gb/s 1310 nm Small Form-Factor Pluggable (SFP) transceiver is a flexible solution as an interface for switches, routers, servers, and other optical links. The transceiver consists of five sections: the LD driver, the limiting amplifier, the digital diagnostics monitor, the 1310 nm FP laser, and the PIN photo-detector. The module can carry data links up to 2 km in a 9/125 µm single mode fiber, and is compatible with the SFP Multi-Sourcing Agreement (MSA).

• Up to 2.5 Gb/s data links

• FP laser transmitter and PIN photodetector

• Up to 2 km on 9/125 µm SMF

• Hot-pluggable SFP footprint

• Duplex LC/UPC type pluggable optical interface

• Low power dissipation

• Metal enclosure, for lower EMI

• RoHS compliant and lead-free

• Supports the Digital Diagnostic Monitoring interface

• SFF-8472 compliant

Absolute Maximum Ratings

Parameter	Symbol	Min.	Typ.	Max.	Unit	Note
Storage Temperature	Ts	‑40		85	°C
Relative Humidity	RH	5		95	%
Power Supply Voltage	VCC	‑0.5		4	V
Signal Input Voltage		‑0.3		Vcc+0.3	V
Receiver Damage Threshold		5			dBm

Recommended Operating Conditions

Parameter	Symbol	Min.	Typ.	Max.	Unit	Note
Case Operating Temperature	Tcase	0		70	°C	SFP‑2G‑LP‑31‑2K
		‑10		80		SFP‑2G‑LP‑31‑2KE
		‑40		85		SFP‑2G‑LP‑31‑2KA
Power Supply Voltage	VCC	3.13	3.3	3.47	V
Power Supply Current	ICC			280	mA
Power Supply Noise Rejection				100	mVp‑p	100 Hz to 1 MHz
Data Rate			2500/2500		Mbps	TX Rate/RX Rate
Transmission Distance				2	kM
Coupled Fiber	Single‑mode fiber					9/125 µm SMF

Transmitter Specifications

Parameter	Symbol	Min.	Typ.	Max.	Unit	Note
Average Output Power	POUT	‑9		‑3	dBm	1
Extinction Ratio	ER	8.2			dB
Center Wavelength	λC	1270	1310	1360	nm	FP Laser
Spectrum Bandwidth (RMS)	σ			3.5	nm	FP Laser
Transmitter OFF Output Power	POff			‑45	dBm
Differential Line Input Impedance	RIN	90	100	110	Ω
Output Eye Mask	Compliant with G.957(class 1 laser safety)					2

Notes:

1: Measured at a 2^23‑1 NRZ PRBS pattern

2: Transmitter eye mask definition

x₃‑x₂	0.2
y₁	0.25
y₂	0.75
y₃	0.25
y₄	0.25

Receiver Specifications

Parameter	Symbol	Min.	Typ.	Max.	Unit	Note
Input Optical Wavelength	λIN	1270		1610	nm	PIN‑TIA
Receiver Sensitivity	PIN			‑18	dBm	1
Input Saturation Power (Overload)	PSAT	‑3			dBm
Loss of Signal Assert	PA			‑19	dBm
Loss of Signal De‑assert	PD	‑35			dBm	2
LOS Hysteresis	PA‑PD	0.5	2	6	dB

Notes

1: Measured with light source 1310 nm, ER=8.2 dB; BER =< 10^‑12 @PRBS=2^23‑1 NRZ

2: When LOS de‑asserted, the RX data+/‑ output is high‑level (fixed)

Electrical Interface Characteristics

Parameter	Symbol	Min.	Typ.	Max.	Unit	Notes
Transmitter
Total Supply Current	ICC			A	mA	1
Transmitter Disable Input‑High	VDISH	2		Vcc+0.3	V
Transmitter Disable Input‑Low	VDISL	0		0.8	V
Transmitter Fault Input‑High	VTxFH	2		Vcc+0.3	V
Transmitter Fault Input‑Low	VTxFL	0		0.8	V
Receiver
Total Supply Current	ICC			B	mA	1
LOSS Output Voltage‑High	VLOSH	2		Vcc+0.3	V	LVTTL
LOSS Output Voltage‑Low	VLOSL	0		0.8	V	LVTTL

Note:

1: A (TX) + B (RX) = 280 mA (Not include termination circuit)

Regulatory Compliance

Feature	Reference	Performance
Electrostatic Discharge(ESD)	IEC/EN 61000‑4‑2	Compatible with standards
Electromagnetic Interference (EMI)	FCC Part 15 Class B EN 55022 Class B (CISPR 22A)	Compatible with standards
Laser Eye Safety	FDA 21CFR 1040.10, 1040.11 IEC/EN 60825‑1, 2	Class 1 laser product
Component Recognition	IEC/EN 60950 , UL	Compatible with standards
ROHS	2002/95/EC	Compatible with standards
EMC	EN61000‑3	Compatible with standards