Ascent Communication Technology

QSFP28 100G DAC Cable

Ascent’s QSFP28 passive direct attach copper twinax cable assemblies are high-performance, cost-effective I/O solutions for 100G Ethernet and 100G Fiber Channel applications.

• QSFP28 conforms to Small Form-Factor SFF8665

• 4-channel full-duplex passive copper cable transceiver

• Supports data rates: 25.78 Gb/s (per channel)

• Maximum aggregate data rate: 100Gb/s (4 x 25.78Gb/s)

• IEEE 802.3bj 100GEBASE-CR4

• Copper link x (x=1m, 2m, 3m, 5m)

• Power Supply: +3.3V

• Low crosstalk

• I2C based two-wire serial interface for EEPROM signature which can be customized

• Operating temperature: 0 °C to +70 °C

• Compatible to QSFP28 MSA

• RoHS Compliant

Absolute Maximum Ratings

Parameter	Symbol	Min.	Typ.	Max.	Unit
Storage Temperature		‑40		+85	°C
Operating Case Temperature	Tc	0		+70	°C
Power Supply Voltage	VCC3	3.14	3.3	3.47	V
Data Rate Per Lane		1		25.78	Gb/s

Note: Damage may occur if the transceiver is subjected to conditions beyond the limits.

High Speed Characteristics

Parameter	Symbol	Min.	Typ.	Max.	Unit	Note
Differential Impedance	RIN, P	9	100	110	Ω
Insertion Loss	SDD2	8		22.48	dB	At 12.8906
Differential Return Loss	SDD11 SDD22	12.45		See 1	dB	At 0.05 to
Differential Return Loss	SDD11 SDD22	3.12		See 2	dB	At 4.1 to 19
Common‑Mode to Common‑Mode Output Return Loss	SCC11 SCC22	2			dB	At 0.2 to 19 GHz
Differential to Common‑Mode Return Loss	SCD11 SCD22	12		See 3	dB	At 0.01 to
Differential to Common‑Mode Return Loss	SCD11 SCD22	10.58		See 4	dB	At 12.89 to
Differential to Common Mode Conversion Loss	SCD21‑IL	10			dB	At 0.01 to
				See 5		At 12.89 to
		6.3				At 15.7 to
Channel Operating Margin	COM	3			dB