Ascent Communication Technology

400G OSFP to 2x200G QSFP56 AOC Breakout Cable

Ascent’s 400G OSFP product is an OSFP to 2x QSFP56, 400Gb/s to 2 x 200Gb/s Active Optical Breakout Cable (AOC) designed for connecting Mellanox NDR switch with OSFP cage to legacy 2 Mellanox HDR switch/HCA QSFP56 cages. The cable is compliant with SFF-8665 for the QSFP56 pluggable solution. It provides connectivity between system units with a OSFP 400Gb/s connector on one side and two separate QSFP56 200Gb/s connectors on the other side, such as a switch and two servers. The cable connects data signals from each of the 8 MMF (Multi Mode Fiber) pairs on the single OSFP end to the four pairs of each of the QSFP56 multiport ends. It supports 53.125Gb/s per channel. Ascent’s active fiber cable solutions provide power-efficient connectivity for data center interconnects. It enables higher port bandwidth, density and configurability at a low cost, and reduced power requirement in the data centers. four-channel full-duplex active optical cable. The OSFP cable has low power dissipation and 8x50g PAM VCSEL/PIN photo detector. Its operating case temperature is 0°C~70°C.

· Four-Channel full-Duplex active optical cable from OSFP to two QSFP56 cable end

· Supports 53.125Gb/s per channel

· Low Power Dissipation, Max 8W on OSFP end, Max. 4W on QSFP56 end.

· 8x50G PAM4 VCSEL/PIN photo detector

· Operating Case Temperature: 0°C ~70

· Compliant to Class 1M Laser Safety

· OSFP form factor compliance to

n Compliant to OSFP Rev. 5.0

n SFF-8679 electrical interface

n SFF-8661 Pluggable Module

n CMIS Rev. 4.0 Management Interface

n IEEE 802.3cd: Physical Layer Specifications and Management Parameters

· QSFP form factor compliance to

n SFF-8636 Management Interface

n IEEE 802.3cd: Physical Layer Specifications and Management Parameters

Absolute Maximum Parameters

Exceeding the limits below may damage the active optical cable permanently.

Parameter	Symbol	Min.	Typ.	Max.	Unit	Ref
Maximum Supply Voltage	T_CC	-0.5		3.6	°C
Storage Temperature	V_sto	-40		85	°C
Case Operating Temperature	T_{OP_1}	0		60	°C	1、2
Case Operating Temperature	T_{op_2}	0		70	°C	2
Relative Humidity	RH	5		85	%

① DDMI temperature reading is measured by the position of T_{op_1}

② Case operating temperature definition:

Top view of module:

Top View of Module

Bottom view of module:

Bottom View of Module

Combination view of module:

Combination View of Module

PARAMETERS

Parameter	Symbol	Min.	Typ.	Max.	Unit	Ref
Supply Voltage	V_cc			12	W
Power Consumption	P_Con			3.63	A
Bit Rate (PAM4)BR	BR		26.5625		GBd	1
Bit Rate (NRZ)	BR		25.78125		Gbps
Pre-FEC Bit Error Ratio (PAM4)	BER			2.4x10^-4		2
Post-FEC Bit Error Ratio (PAM4)	BER			10^-12
Pre-FEC Bit Error Ratio (NRZ)	BER			5x10^-5
Post-FEC Bit Error Ratio (NRZ)	BER			10^-12
Center Wavelength	λ_c	840		868	nm	3
Beam Divergence Angle			23		°
Number of Lanes
Management Interface		Serial, I2C-based, maximum frequency 400 kHz				4
Logic Input Voltage High	V_ih	2		V_cc+0.3	V
Logic Input Voltage Low	V_il	-0.3		0.8	V

① Single lane

② PRBS31Q test pattern is used.

③ As defined by IEEE Std. 802.3bs ™/D3.5

④ As defined by SFF-8636

Electrical Characteristics for OSFP

Parameter	Symbol	Min.	Typ.	Max.	Unit	Ref
Transmitter at TP1a
AC Common-Mode Output Voltage (RMS)				17.5	mV
Differential Peak-to-Peak Output Voltage (Transmitter Disabled)				35	mV
Differential Peak-to-Peak Output Voltage (Transmitter Enabled)				880	mV
Eye Symmetry Mask Width	ESMW		0.22		UI
Eye Height, Differential	EH	32			mV
Differential Output Return Loss		See Eq. 1
Common to Differential Mode Conversion Return Loss		See Eq. 2
Differential Termination Mismatch		10			%
Transition Time (20% To 80%)	Tr, Tf	10			ps
Receiver At TP4
Far-End Eye height, Differential		30
Far-End Pre-Cursor ISI Ratio		-4.5		2.5	%
Differential Output Return Loss	λ	See Eq. 1
Common to Differential Mode Conversion Return Loss		See Eq. 2
Differential Termination Mismatch		10			%
Transition Time (20% To 80%)	Tr, Tf	10			ps
DC Common Mode Voltage		-350		2850	mV

where

f is the frequency in GHz, RLdc is the CAUI-4 Chip-to-module input differential to common mode input return loss

where

f is the frequency in GHz, RLdc is the CAUI-4 Chip-to-module input differential to common mode input return loss

Electrical Characteristics for QSFP

Parameter	Symbol	Min.	Typ.	Max.	Unit	Ref
Transmitter at TP1a
AC Common-Mode Output Voltage (RMS)				17.5	mV
Differential Peak-to-Peak Output Voltage (Transmitter Disabled)				35	mV
Differential Peak-to-Peak Output Voltage (Transmitter Enabled)				880	mV
Eye Symmetry Mask Width	ESMW		0.22		UI
Eye Height, Differential	EH	32			mV
Differential Output Return Loss		See Eq. 1
Common to Differential Mode Conversion Return Loss		See Eq. 2
Differential Termination Mismatch		10			%
Transition Time (20% To 80%)	Tr, Tf	10			ps
Receiver At TP4
Far-End Eye height, Differential		30
Far-End Pre-Cursor ISI Ratio		-4.5		2.5	%
Differential Output Return Loss	λ	See Eq. 1
Common to Differential Mode Conversion Return Loss		See Eq. 2
Differential Termination Mismatch		10			%
Transition Time (20% To 80%)	Tr, Tf	10			ps
DC Common Mode Voltage		-350		2850	mV

where

f is the frequency in GHz, RLdc is the CAUI-4 Chip-to-module input differential to common mode input return loss

where

f is the frequency in GHz, RLdc is the CAUI-4 Chip-to-module input differential to common mode input return loss

General Product Characteristics

Parameter	Value	Unit	Comments
Module Form Factor	OSFP and QSFP		Module Form Factor
Number Of Lanes	8 TX and 8 RX
Maximum Aggregate Data Rate	425(OSFP) 212.5(QSFP)	Gb/s
Maximum Data Rate Per Lane	53.125	Gb/s
Standard Cable Lengths	3, 5, 7,10, 15, 20	m	Other lengths may be available upon request
Protocols Supported	InfiniBand, Ethernet
Electrical Interface And Pinout	60-pin edge connector (OSFP) 38-pin edge connector (QSFP56)		Pin-out as defined by OSFP Rev. 5.0 & QSFP SFF8679
Standard Optical Cable Type	Multimode OM3(≤70m) Multimode OM4(<100m)
Maximum Power Consumption Per End	8 (OSFP) and 4 (QSFP56)	W	Varies with output voltage swing and pre-emphasis settings
Management Interface	Serial, I2C-based, 400 kHz maximum frequency		As defined by CMIS Rev 4.0

The force specification for AOC is in the list below:

Parameter	Min.	Max.	Unit.	Comments.
Module Insertion		40 (OSFP) 40 (QSFP56)	N
Module Extraction		30 (OSFP) 30 (QSFP56)	N
Module Retention	125 (OSFP) 90 (QSFP56)		N
Insertion And Removal Cycles	50		Cycle
Cable Outer Diameter	2.9	3.1	mm
Fiber Cable Material	Aqua, OFNP, Corning fiber

Pin Desciptions (compliant OSFP Rev. 5.0)

Pin	Symbol		Description	Plug Sequence
1	GND		Ground	1
2	TX2p		Transmitter Data Non-Inverted	3
3	TX2n		Transmitter Data Inverted	3
4	GND		Ground	1
5	TX4p		Transmitter Data Non-Inverted	3
6	TX4n		Transmitter Data Inverted	3
7	GND		Ground	1
8	TX6p		Transmitter Data Non-Inverted	3
9	TX6n		Transmitter Data Inverted	3
10	GND		Ground	1
11	TX8p		Transmitter Data Non-Inverted	3
12	TX8n		Transmitter Data Inverted	3
13	GND		Ground	1
14	SCL		2-wire Serial interface clock	3
15	VCC		+3.3V Power supply	2
16	VCC		+3.3V Power supply	2
17	LPWn/PRSn		Low-Power Mode / Module Present	3
18	GND		Ground	1
19	RX7n		Receiver Data Inverted	3
20	RX7p		Receiver Data Non-Inverted	3
21	GND		Ground	1
22	RX5n		Receiver Data Inverted	3
23	RX5p		Receiver Data Non-Inverted	3
24	GND		Ground	1
25	RX3n		Receiver Data Inverted	3
26	RX3p		Receiver Data Non-Inverted	3
27	GND		Ground	1
28	RX1n		Receiver Data Inverted	3
29	RX1p		Receiver Data Non-Inverted	3
30	GND		Ground	1
31	GND		Ground	1
32	RX2p		Receiver Data Non-Inverted	3
33	RX2n		Receiver Data Inverted	3
34	GND		Ground	1
35	RX4p		Receiver Data Non-Inverted	3
36	RX4n		Receiver Data Inverted	3
37	GND		Ground	1
38	RX6p		Receiver Data Non-Inverted	3
39	RX6n		Receiver Data Inverted	3
40	GND		Ground	1
41	RX8p		Receiver Data Non-Inverted	3
42	RX8n		Receiver Data Inverted	3
43	GND		Ground	1
44	INT/RSTn		Module Interrupt / Module Reset	3
45	VCC		+3.3V Power	2
46	VCC		+3.3V Power	2
47	SDA		2-wire Serial interface data	3
48	GND		Ground	1
49	TX7n		Transmitter Data Inverted	3
50	TX7p		Transmitter Data Non-Inverted	3
51	GND		Ground	1
52	TX5n		Transmitter Data Inverted	3
53	TX5p		Transmitter Data Non-Inverted	3
54	GND		Ground	1
55	TX3n		Transmitter Data Inverted	3
56	TX3p		Transmitter Data Non-Inverted	3
57	GND		Ground	1
58	TX1n		Transmitter Data Inverted	3
59	TX1p		Transmitter Data Non-Inverted	3
60	GND		Ground	1
Name		Direction	Description
TX[8:1]p		input	Transmit differential pairs from host to module.
TX[8:1]n		input
RX[8:1]p		output	Receiver differential pairs from module to host.
RX[8:1]n		output
SCL		bidir	2-wire serial clock signal. Requires pull-up resistor to 3.3V on host.
SDA		bidir	2-wire serial data signal. Requires pull-up resistor to 3.3V on host.
LPWn/PRSn		bidir	Multi-level signal for low power control from host to module and module presence indication from module to host. This signal requires the circuit as described in Section 11.5.3
INT/RSTn		bidir	Multi-level signal for interrupt request from module to host and reset control from host to module. This signal requires the circuit as described in Section 11.5.2
VCC		power	3.3V power for module.
GND		ground	Module Ground. Logic and power return path.