100G PAM4 DSP Driverless
Product Brief


The MxL93515 and MxL93516 are highly integrated PAM4 DSP devices that enable a 100Gbps optical interconnect using 100Gbps over a single optical wavelength 100G/lambda.

Both are optimized for four-level pulse amplitude modulation (PAM4) and non-return-to-zero (NRZ) applications and are available in a 7mm x 8.5mm package.

The MxL93515 has a differential pair of optical outputs.

The MxL93516 has a single-ended laser driver that is required for the EA-EML optics.
The devices have a high-speed electrical interface with four transmit (Tx) and receive (Rx) input/output (I/O) paths for NRZ applications and two Tx and Rx I/O paths for PAM4 applications that connect electrically through a module connector to the host ASIC. They also have a high-speed optical side interface that has one Tx and Rx that connect through the optical components to the optical fibers.

The electrical interface supports 25Gbps NRZ or 50Gbps PAM4 signaling over an electrical channel with up to 14dB channel loss, including the host connector.

The optics interface supports 100Gbps PAM4 signaling to enable 500m DR, 2km FR, and 10km LR use cases.

The devices support DSP functions including Tx digital predistortion (DPD), transmit pre-emphasis (Tx FIR), receive feed-forward equalization (Rx FFE), and decision feedback equalization (DFE) that is required for 56 Gbaud optics.

They have exceptional signal integrity for 56Gbaud signals in a compact footprint, suitable for next generation optical module form factors.


  • 100G capacity that enables 100G DR, FR, and LR requirements
  • The MxL93516 has a single EA_EML driver with a 1.8VPP SE swing and required connect to the TOSA
  • The MxL93515 has a differential pair output with 0.7V differential PP swing feeding to the TOSA
  • Tx equalization includes pre-emphasis, digital predistortion, and reflection cancellation
  • Rx equalization includes continuous time linear (CTLE), multi-tap FFE and DFE, and reflection cancellation
  • Integrated crystal oscillator eliminates the need for a costly reference clock source
  • Digital I/O compatibility with the host processor. This removes the need for level shifters and saves valuable module board space
  • Small package size to enable the QSFP28, SFP-DD and DSFP space requirements
  • Bit error rate (BER) monitoring
  • Signal-to-noise ratio (SNR) reporting for each receiver on both electrical and optical interfaces
  • Diagnostic loop-backs and test pattern generation and checking
  • SPI and I2C slave interface to communicate to module micro-controller unit (MCU)
  • SPI master for flash memory interface
  • I2C master interface for TIA direct control
  • Embedded CPU for real-time control
  • Squelch function when loss of signal (LOS) or loss of lock (LOL) is detected
  • Error correcting code (ECC) in the CPU memories provide 2-bit error detection and a single-bit error correction


Contact Sales to request additional information.


  • QSFP28 optical modules
  • SFP-DD optical modules
  • DSFP optical modules

Design Tools


Parts & Purchasing

Part Number Pkg Code Min Temp Max Temp Status Buy Now Order Samples
MxL93515-AY-T -5 85 PRE
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Part Status Legend
Active - the part is released for sale, standard product.
EOL (End of Life) - the part is no longer being manufactured, there may or may not be inventory still in stock.
CF (Contact Factory) - the part is still active but customers should check with the factory for availability. Longer lead-times may apply.
PRE (Pre-introduction) - the part has not been introduced or the part number is an early version available for sample only.
OBS (Obsolete) - the part is no longer being manufactured and may not be ordered.
NRND (Not Recommended for New Designs) - the part is not recommended for new designs.

Quality & Environmental Data

Click on the links above to download the Certificate of Non-Use of Hazardous Substances.

Additional Quality Documentation may be available, please Contact Support.