ASNT8161-KMF

Overview

The ASNT8161-KMF is a programmable half-rate clock recovery (CR) circuit designed for input data rates from 36 Gbps to 72 Gbps. It supports both NRZ and PAM4 data formats and utilizes six on-chip voltage-controlled oscillators (VCOs) to cover a wide frequency range. The device accepts CML or LVDS reference clocks and provides a half-rate CML clock output up to 36 GHz. Powered by a single +3.3V or -3.3V supply, it consumes 1.7W at maximum speed. Control is managed via a 3-wire SPI interface, allowing adjustment of VCO selection, charge pump current, and signal peaking.

Feature Summary

• Half-rate clock recovery with input data range of 36 Gbps to 72 Gbps
• Supports NRZ and PAM4 input data formats
• Six on-chip VCOs selectable via digital control for broad frequency coverage
• Integrated input and output signal peaking adjustment capabilities

Applications

• High-speed serial link clock recovery systems
• Telecommunications infrastructure requiring 36G-72G data rates
• Test and measurement equipment utilizing PAM4 signaling

Procurement Notes

Verify the specific package variant and revision level against the latest manufacturer datasheet before procurement. Confirm power supply configuration requirements, as the device supports both positive (+3.3V) and negative (-3.3V) supply polarities, which necessitates distinct PCB layouts. Ensure external loop filter components match the recommended schematic values for stable operation.

Selection Notes

Select this component when a half-rate clock recovery solution is required for data rates between 36 Gbps and 72 Gbps. Consider the available VCO bands defined by the vcosel parameter to ensure the target frequency falls within the operational range. Evaluate the need for PAM4 support and input/output peaking adjustments, which are unique features of this IC compared to standard CR circuits.

Part Context

The ASNT8161-KMF belongs to the ASNT series of clock recovery circuits manufactured by Advanced Science And Novel Technology Company, Inc. It is housed in a custom 64-pin CQFP package with a center heat slug for thermal management. The part number suffix 'KMF' indicates the specific package type and pinout configuration provided by the manufacturer.

Replacement Considerations

No publicly confirmed substitute part numbers are available in the source documentation. Designers should evaluate compatibility based on pinout, electrical specifications, and package dimensions if considering alternative vendors.

FAQ

What input data formats does the ASNT8161-KMF support?

The device supports both NRZ (Non-Return-to-Zero) and PAM4 (Pulse Amplitude Modulation 4-level) input data formats.

How is the operating frequency of the internal VCO selected?

The desired working frequency is selected using the 3-bit digital control vcosel via the SPI interface, which chooses one of six on-chip VCO bands.

What is the required external filter configuration for the clock recovery loop?

An off-chip passive filter must be connected to the ftr pin. The recommended schematic includes a 22nF capacitor, a 66 Ohm resistor, and a 390pF capacitor.