Ascent Communication Technology

1.25G SFP ZX 1550 nm 80 km

ASCENT’s SFP-AG-LP-51-80 Small Form Factor Pluggable (SFP) transceivers are flexible solution as an interface for switches, routers, servers, and other optical links. They are compatible with the Small Form Factor Pluggable Multi-Sourcing Agreement (MSA). The transceiver consists of five sections: the LD driver, the limiting amplifier, the digital diagnostic monitor, the DFB laser and the PIN photo-detector. The module data link up to 80 km in 9/125 µm single mode fiber. The optical output can be disabled by a TTL logic high-level input of Tx Disable, and the system also can disable the module via I2C. Tx Fault is provided to indicate that degradation of the laser. Loss of signal (LOS) output is provided to indicate the loss of an input optical signal of receiver or the link status with partner. The system can also get the LOS (or Link)/Disable/Fault information via I2C register access.

• Up to 1.25 Gb/s data links with DDM

• DFB laser transmitter and PIN photo-detector

• Up to 80 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

• Support Digital Diagnostic Monitoring interface

• Single +3.3V power supply

• Compliant with SFF-8472

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	T_case	0		70	°C °C °C	SFP‑AG‑LP‑51‑80‑A
		‑10		80		SFP‑AG‑LP‑51‑80E‑A
		‑40		85		SFP‑AG‑LP‑51‑80U‑A
Power Supply Voltage	V_CC	3.13	3.3	3.47	V
Power Supply Current	I_CC			300	mA
Power Supply Noise Rejection				100	mVp‑p	100 Hz to 1 MHz
Data Rate			1250/1250		Mbps	TX Rate/RX Rate
Transmission Distance				80	km
Coupled Fiber	Single‑mode fiber					9/125 µm SMF

Transmitter Specifications

Parameter	Symbol	Min.	Typ.	Max.	Unit	Note
Average Output Power	P_OUT	0		5	dBm	1
Extinction Ratio	ER	9			dB
Center Wavelength	λ_C	1530	1550	1570	nm	DFB Laser
Side Mode Suppression Ratio	SMSR	30			dB	DFB Laser
Spectrum Bandwidth(‑20dB)	σ			1	nm
Transmitter OFF Output Power	P_Off			‑45	dBm
Differential Line Input Impedance	RIN	90	100	110	Ω
Output Eye Mask	Compliant with IEEE802.3 z (class 1 laser safety)					2

Notes

1. Measure at 2⁷‑1 NRZ PRBS pattern.

2. Transmitter eye mask definition.

Receiver Specifications

Parameter	Symbol	Min.	Typ.	Max.	Unit	Note
Input Optical Wavelength	λ_IN	1270		1610	nm	PIN‑TIA
Receiver Sensitivity	P_IN			‑26	dBm	1
Input Saturation Power (Overload)	P_SAT	‑3			dBm
Loss Of Signal Assert	P_A			‑26	dBm
Loss Of Signal De‑assert	P_D	‑38			dBm	2
LOS Hysteresis	P_A‑P_D	0.5	2	6	dB

Notes

1. Measured with Light source 1550 nm, ER = 9 dB; BER ≤ 10^‑12 @ PRBS=2⁷‑1 NRZ

2. When LOS de‑asserted, the RX data± output is high‑level (fixed)

Electrical Interface Characteristics

Parameter	Symbol	Min.	Typ.	Max.	Unit	Note
Transmitter
Total Supply Current	I_CC			A	mA	1
Transmitter Disable Input‑High	V_DISH	2		Vcc+0.3	V
Transmitter Disable Input‑Low	V_DISL	0		0.8	V
Transmitter Fault Input‑High	V_TxFH	2		Vcc+0.3	V
Transmitter Fault Input‑Low	V_TxFL	0		0.8	V
Receiver
Total Supply Current	I_CC			B	mA	1
LOSS Output Voltage‑High	V_LOSH	2		Vcc+0.3	V	LVTTL
LOSS Output Voltage‑Low	V_LOSL	0		0.8	V	LVTTL

Notes

1. A (TX) + B (RX) = 300mA (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