400G QSFP-DD DCO ZR

Ascent’s QDD-400G-ZR QSFP-DD Digital Coherent Optic Modules are 400 Gb/s Quad Small Form Factor Pluggable- double density (QSFP-DD) transceivers designed for long distance optical communication applications over a standard pair of G.652 Single-Mode Fiber (SMF). The QSFP-DD DCO modules based on 400G DP-16QAM supporting extended C-band, polarization diversity coherent detection, and advanced electronic link equalization. Chromatic dispersion compensation can be applied to the receiving side of the demodulator. This module is managed to utilize the Two Wire Interface that is specified in the Common Management Interface Specification (CMIS). The module uses a 76-pin QSFP-DD MSA QSFP-DD Hardware Specification connector for all electrical interfaces with the host card, whereas the optical interfaces on the line side are provided through the optical receptacles on the QSFP-DD. The module can be portioned into three functional parts: TX path, RX path and Control & Power block. The host interface is comprised of a total of 8 high-speed SerDes lanes. This allows module to support multiple client application mode for 400GbE application.

· Support Flex-grid channel spacing DWDM in C-band

· Support Client-side Interfaces: 400GAUI-8

· Support Line-side DP-16QAM with CFEC

· Standard QSFP-DD type 2 form factor

· 76pin QSFP-DD MSA compliant connector

· Compliant to CMIS 5.0

· Compliant to OIF Implementation Agreement for Coherent CMIS, Rev 01.1

· OIF-400ZR-01.0_reduced2.pdf

· RoHS compliant

Absolute Maximum Ratings

The absolute maximum ratings given in the table below define the damage thresholds. Hence, the component shall withstand the given limits without any irreversible damage.

Parameter	Min.	Max.	Unit	Note
Storage Temperature	-40	85	°C
Storage Humidity (Relative)	-	85	%	no-condensing
Case Temperature	0	75	°C
Operating Humidity (Relative)	-	85	%	no-condensing
Short term Operating Case Temperature		80	°C	<24 hours
Power Supply Absolute Range	-0.3	3.63	V
RX Optical Maximum Input Power	-	10	dBm

Operating Conditions

Parameter Operating Case Temperature	Min. 0	Max. 75	Unit °C	Note
Operating Humidity (Relative)	-	85	%	no-Condensing
Power Supply Operating Range	3.135	3.465	V
RX Optical Input Power	-	0	dBm

Power Supply

The 400G ZR QSFP-DD DCO is a Power Class 8 module. In order to avoid exceeding the host system power capacity, upon hot-plug, power cycle or reset, all QSFP-DD modules shall power up in Low Power Mode if LPMode is asserted. If LPMode is not asserted the module will proceed to High Power Mode without host intervention. Specification values for maximum instantaneous, sustained and steady state currents at each power class are given in below table. The power supply requirements are specified in the table below.

Parameter	Min.	Typ.	Max.	Unit	Note
3.3V DC Power Supply Voltage	3.135	3.3	3.465	V
3.3V DC Power Supply Current			7	A
Power Dissipation			18	W
Low Power Consumption			1.5	W
Module Inrush Current			100	mA/us
Turn-off Current	-100			mA/us
Power Supply Noise			25	mV

High Speed Electrical Specifications

The transmitter and receiver comply with the CEI-56G-VSR-PAM4 electrical specification (OIF-CEI-04.0).

The data lines are AC-coupled and terminated in the module per the following figure from the QSFP-DD MSA. The high-speed signals follow the electrical specifications of CEI-56G-VSR-PAM as defined in OIF-CEI- 04.0.

The high speed signals consist of 8 transmit and 8 receive differential pairs identified as TX[8:1]p / TX[8:1]n and RX[8:1]p / RX[8:1]n. These signals can be operated in 400GAUI-8 depending on the capability of the host. 400GAUI-8 mode provides 8 differential lanes using PAM4 signaling operating at 26.5625 GBaud. This results in 8 lanes of 50Gb/s for a total of 400Gb/s. This mode allows connection to PMD configurations of 400GUAI-8.

The following electrical characteristics are defined over the Recommended Operating Environment unless otherwise specified.

Electrical Characteristics for Transmitter

Parameter	Min. Typ.	Max.	Unit	Note
Signal Rate, each Lane	26.5625±100ppm		GBaud
Differential Peak-Peak Input Voltage Tolerance		900	mVpp

Electrical Characteristics for Receiver

Parameter	Min. Typ.		Max.	Unit	Note
Signal Rate, each Lane	26.5625±100ppm
Differential Peak-Peak Input Voltage Tolerance		750	900	mVpp
Transition Time, 20% to 80%		9.5		ps

Optical Transmitter

Parameter	Min.	Typ.	Max.	Unit	Note
Transmitter Frequency Range	191.3	193.7	196.1	THz	1
Laser Frequency Stability	-1.8		1.8	GHz	Frequency stability relative to ITU grid.
Laser Frequency Accuracy	-1.8		1.8	GHz
Laser Frequency Fine Tuning Range	-6.0		6.0	GHz
Fine Tuning Resolution		100		MHz
Channel Tuning Speed	-		60	s
Laser LineWidth			100	kHz
Transmitter Output Power Range	-10		-6	dBm
Transmitter Laser Disable Time			180	ms
Output Power Stability	-0.5		0.5	dB	2
Output Power Accuracy	-2		2	dB	3
Transmitter Turn-up Time from Cold Start	-		120	s
Transmitter OSNR (Inband)	34		-	dB/0.1nm
Transmitter Back Reflectance	-		-24	dB
Transmitter Output Power with TX Disabled	-		-20	dBm

Transmitter Polarization Dependent Power	-		1.5	dB	Power deference between X and Y polarization

Notes:

1. C band 75GHz ITU-T grid. Frequency range over which the specifications hold unless noted otherwise.

2. Difference over temperature, time, wavelength and aging.

3. Difference between the set value and actual value over aging.

Optical Receiver

Parameter	Min.	Typ.	Max.	Unit	Note
Receiver Frequency Range	191.3	193.7	196.1	THz
Input Power Range	-12		0	dBm	1
OSNR Sensitivity		24	26	dB/0.1nm
Receiver Sensitivity			-20	dBm	2
Los Assert	-20		-16	dBm
Los Hysteresis	1.0		2.5	dB
CD Tolerance	2400			ps/nm	Tolerance to Chromatic Dispersion
PMD Tolerance	10			ps	3
Peak PDL Tolerance	3.5			dB	4
Tolerance to Change in SOP	50		-	rad/ms
Input Power Transient Tolerance	-2		2	dB	5
Input Power Reading Accuracy	-2		2	dB
Optical Return Loss	-20			dB	Optical reflectance at Rx connector input.
Receiver Turn-up Time from Cold Start	-		120	s	6

Notes:

1. Signal power of the channel at the OSNR Penalty < 0.5dB

2. Input power needed to achieve post FEC BER < 1E-15 when OSNR Tolerance > 26 dB/0.1nm

3. Tolerance to PMD with < 0.5 dB penalty to OSNR sensitivity.

4. Tolerance to peak PDL with < 1.3 dB penalty to OSNR sensitivity when change in SOP is < =1 rad/ms.

5. Tolerance to change in input power with<0.5 dB penalty to OSNR sensitivity.

6. From module reset, with valid optical input signal present.

Loopback

The module support loopback functionality. The host loopback (Loopback ①) and the network loopback (Loopback ②) are shown at bellowing figure. For details on controlling the loopback mode, please refer to Reference [2]. In optional loopback, TXn is looped back to RXn, for example TX0+ to RX0+, on both host and media side.

Insertion, Extraction and Retention Force

Parameter	Min.	Max.	Unit	Note
Insertion Force		90	N
Extraction Force		50	N
Retention Force	90		N

EMI, EMC and ESD Specifications

The module is compliant with the requirements listed in the table below when installed in the host equipment.

Parameter	Reference	Value	Unit	Note
ESD Immunity	IEC 61000-4-2	8	kV	Contact Discharge
		15	kV	Air Discharge
ESD (HBM model)	JEDEC JESD22-A114-B	1	kV	High-Speed Contacts
		2	kV	Other pins
EMC Immunity	IEC 61000-4-3
EMI Emission	FCC Class B

Laser Safety

This is a Class 1 Laser Product according to IEC 60825-1:2007. This product complies with 21 CFR 1040.10 and 1040.11 except for deviations pursuant to Laser Notice No. 50, dated (June 24, 2007).

Don’t directly look into the transmitter fiber connector at any time while the module is in operation.