Ascent Communication Technology

800G OSFP DAC Cable

The OSP8-4OSP2-DAC is a high-performance 800Gbps passive Direct Attach Copper (DAC) breakout cable designed for InfiniBand NDR and high-speed data center interconnects. This cable enables a direct breakout from a single 800G OSFP port to four 200G OSFP ports, allowing flexible connectivity between high-density switches and compute nodes in modern AI and HPC clusters. The cable supports PAM4 signaling up to 106.25Gbps per lane, delivering an aggregate bandwidth of 800Gbps over copper connections up to 3 meters. With its passive copper design, the OSP8-4OSP2-DAC offers ultra-low latency, minimal power consumption, and high reliability, making it ideal for short-reach interconnections inside racks or between adjacent racks in high-performance computing environments. Compliant with the OSFP MSA specification, the cable includes built-in EEPROM functionality to provide cable identification and monitoring capabilities via the host system. The OSP8-4OSP2-DAC is designed to deliver a cost-effective and energy-efficient solution for high-bandwidth GPU clusters, InfiniBand fabrics, and large-scale AI training infrastructure.

· OSFP Module compliant to OSFP MSA

· Transmission data rate up to PAM4 106.25Gbps per channel

· Enable 800Gb/s to 4x200Gb/s Transmission

· Link length up to 3m

· Built-in EEPROM functions

· Operating case temperature 0°C to +70°C

· RoHS2.0 compliant

Absolute Maximum Ratings

Parameter	Symbol	Min	Typ	Max	Unit
Supply Voltage	Vcc	3.13	3.3	3.47	V
Storage temperature	Ts	-40		85	°C
Operating Case temperature	Tc	0		70	°C
Humidity	Rh	5		85	%
Data Rate			800		Gbps

Recommended Operating Conditions

Parameter	Symbol	Min	Typ	Max	Unit
Length	L	0.5		3.0	M
AWG		28		25	AWG
Jacket Material	HAIRTAIL+ Technology Net, Sliver Gray

Electrical Characteristics

Parameter	Symbol	Min	Typ	Max		Unit
Resistance	Rcon			3		ohm
Insulation Resistance	Rins			10		Mohm
Raw Cable Impedance	Zca	95		110		ohm
Mated Connector Impedance	Zmated	85		110		ohm
Maximum Insertion Loss at 26.56 GHz	SDD21	11		18	1.5M	dB
				19.75	2.0M	dB
				25.3	3.0M	dB
Differential to Common-Mode Return Loss	SCD11/22	For 0.05 ≤f ≤40 GHz, Where f is the frequency in GHz				dB
Differential to Common-Mode Conversion Loss	SCD21-S DD21	For 0.05 ≤f ≤40 GHz, Where f is the frequency in GHz				dB
Common-Mode to Common-Mode Return Loss	SCC11/22	For 0.05 ≤f ≤40 GHz, Where f is the frequency in GHz				dB
Minimum COM	COM	3				dB