LFE2-20E-5FN256I Lattice, LFE2-20E-5FN256I Datasheet - Page 734

• Manufacturer Part Number: LFE2-20E-5FN256I
• Description: IC FPGA 21KLUTS 193I/O 256FPBGA
• Manufacturer: Lattice
• Series: ECP2r

Specifications of LFE2-20E-5FN256I

• Number Of Logic Elements/cells: 21000
• Number Of Labs/clbs: 2625
• Total Ram Bits: 282624
• Number Of I /o: 193
• Number Of Gates: -
• Voltage - Supply: 1.14 V ~ 1.26 V
• Mounting Type: Surface Mount
• Operating Temperature: -40°C ~ 100°C
• Package / Case: 256-BGA
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 220-1170; LFE2-20E-5FN256I; Q6411457

Lattice Semiconductor
Figure 16-7. Enter the Encryption Key
Verifying a Configuration
As an additional security step when an encrypted bitstream is used, the readback path from the SRAM fabric is
automatically blocked. In this case, for all ports, a read operation will produce all zeros. However, even when the
configuration bitstream has been encrypted and readback disabled, there are still ways to verify that the bitstream
was successfully downloaded into the FPGA.
If the SRAM fabric is programmed directly, the data is first decrypted and then the FPGA performs a CRC on the
data. If all CRCs pass, configuration was successful. If a CRC does not pass, the DONE pin will stay low and INITN
will go from high to low (for more information on this type of error, refer to TN1108,
Usage
3. Double-click on the line in the chain containing the LatticeECP2. This will open the Device Information win-
4. Enter the desired 128-bit key. The key can be entered in Hexadecimal or ASCII. Hex supports 0 through f
5. Programming the Key Lock secures the 128-bit encryption key. Once the Key Lock is programmed and the
6. From the main ispVM window (Figure 16-3) click on the green GO button on the toolbar to program the key
Guide.
dow (see Figure 5). From the Device Access Options drop-down box select Security Mode, then click on
the Security Key button to the right. The window will look similar to Figure 16-7.
and is not case sensitive. ASCII supports all alphanumeric characters, as well as spaces, and is case sen-
sitive. This key must be the same as the key used to encrypt the bitstream. The LatticeECP2/M will only
configure from an encrypted file whose encryption key matches the one loaded into the FPGA’s one-time
programmable fuses. Note: be sure to remember this key. Once the Key Lock is programmed, Lattice
Semiconductor cannot read back the one-time programmable key.
device is power cycled, the 128-bit encryption key cannot be read out of the device. When satisfied, type
Yes to confirm, then click Apply.
into the LatticeECP2/M one-time programmable fuses. When complete, the LatticeECP2/M will only con-
figure from a bitstream encrypted with a key that exactly matches the one just programmed.
a. The key can be saved to a file using the Save to File button. The key will be encrypted using an 8-
character password that the user selects. The name of the file will be <project_name>.bek. In the
future, instead of entering the 128-bit key, simply click on Load from File and provide the password.
16-6
Configuration Encryption Usage Guide
LatticeECP2/M S-Series
LatticeECP2/M sysCONFIG