Ascent Communication Technology

25G SFP28 1310 nm 10 km

Ascent’s SFP28 transceivers are designed for use in 25G Gigabit Ethernet links with distances up to 10 km over single-mode fiber. These transceivers include a PIN photo detector diode and FP transmitter. Digital diagnostic functions are available via a 2-wire interface.

• Up to 10 km transmission distance

• FP transmitter and PIN photo-detector

• Duplex LC connector

• Metal enclosure, for lower EMI

• Electrical interface compliant to SFF-8431 specifications

• 2-wire interface for management specifications compliant with SFF-8472

• Compliant with SFP+ MSA

• Single 3.3V power supply

• Power dissipation < 1.2W

• Case operating temperature range: Commercial: 0 °C to +70 °C

• Industrial: -40 °C to +85 °C

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	‑0.3	‑	4	V

Recommended Operating Conditions

Parameter	Symbol	Min.	Typ.	Max.	Unit	Note
Case Operating Temperature	Tcase	0	‑	70	°C	Commercial
		‑40	‑	85	°C	Industrial
Power Supply Voltage	VCC	3.14	3.3	3.47	V
Power Supply Current	ICC	‑	‑	300	mA	Commercial
		‑	‑	360	mA	Industrial
Data Rate	BR	24.3	25.78	26.5	Gbps
Transmission Distance	TD	‑	‑	10	km
Coupled Fiber	Single‑mode fiber					9/125 µm SMF

Electrical Characteristics

Parameter	Symbol	Min.	Typ.	Max.	Unit	Note
Supply Voltage	Vcc	3.14	3.3	3.46	V
Supply Current	Icc			300	mA	Commercial
				360	mA	Industrial
Transmitter
Input Differential Impedance	Rin		100		Ω	1
Differential Data Input Swing	V_in,pp	180		800	mV
Transmit Disable Voltage	V_DIS	Vcc‑1.3		Vcc	V
Transmit Enable Voltage	V_EN	Vee		Vee+ 0.8	V	2
Receiver
Differential Data Output Swing	V_out,pp	300		850	mV	3
LOS Fault	V_LOS fault	Vcc‑1.3		V_CCHOST	V	4
LOS Normal	V_LOS norm	Vee		Vee+0.8	V	4

Notes:

1. Connected directly to TX data input pins. AC coupled thereafter.

2. Or open circuit.

3. Into 100 Ω differential termination.

4. Loss Of Signal is LVTTL. Logic 0 indicates normal operation; logic 1 indicates no signal detected.

Optical Characteristics

Parameter	Symbol	Min.	Typ.	Max.	Unit	Note
Transmitter
Average Output Power	P_OUT	‑5		2	dBm	1
Optical Wavelength	λ	1295		1325	nm
Spectral Width (RMS)	σ			1	nm
Optical Extinction Ratio	ER	3.5			dB
Receiver
Rx Sensitivity	R_SEN			‑13.3	dBm	2
Input Saturation Power (Overload)	P_SAT	0.5			dBm
Input Optical Wavelength	λC	1295		1325	nm
LOS De ‑Assert	LOSD			‑14	dBm
LOS Assert	LOSA	‑30			dBm
LOS Hysteresis		0.5			dB