MotoHawk FPGA Memory Retention Estimate

This block estimates the remaining retention of the FPGA's Flash Memory.

Block ID

FPGA Memory Retention Estimate

Library

motohawk_FPGA_lib

Description

The ability of the FPGA's flash memory to retain what it has been programmed with is impacted by the operating temperature experienced by the module since the FPGA was last programmed. Reprogramming the FPGA resets the retention.

This block estimates the remaining retention of the FPGA's Flash Memory by estimating consumed retention and then predicting future retention using historical module operation data. Consumed retention factors in that retention is directly impacted by temperature through the use of the "Temp Modifier" attribute that is part of the FPGA's retention characterization and logged histogram data of operation versus temperature.

The consumed retention is converted into remaining retention by subtraction from the FPGA's total retention characteristic. This value is converted into a percentage if Percent has been chosen as the output. The historical data is used to estimate what portion of time the module will spend at various operating temperatures in the future when the Operating Hours output is selected. The amount of time spent at the different operating temperatures is then used to factor in how the estimated remaining retention will be impacted by temperature.

The workings of the calculation can be explored using Simulink because this block is a masked subsystem. The historical operating data and FPGA retention characterization is recovered from the module using the Get Module Data block. This block can be used directly to explore different retention prediction algorithms.

If a retention estimate is required for a specific temperature, consider using the FPGA Memory Retention Estimate At Temperature block.

Block Parameters

Parameter Field	Values	Comments/Description
Retention Units	Dropdown Operating Hours, Percent	Select the desired units of the output. The Percent and Operating Hours estimates are based upon estimating what memory retention remains and then predicting how this translates if future operation trends in the same manner as past operation so far as operating temperature is concerned.