LFEC10E-3F256C Lattice Semiconductor Corp., LFEC10E-3F256C Datasheet - Page 92

• Manufacturer Part Number: LFEC10E-3F256C
• Description: Latticeecp/ec Family of Fpga Devices Has Been Optimized to Deliver Mainstream Fpga Features at Low Cost.for Maximum Performance And Value, The Latticeecp (EConomy Plus) Fpga Concept Combines an Efficient Fpgafabric With High-speed Dedicated Functions
• Manufacturer: Lattice Semiconductor Corp.

Lattice Semiconductor
age that is used by the DQS transition detector circuit. This voltage divider is only present on V
able on V
Lattice technical note number TN1050, LatticeECP/EC DDR Usage Guide.
Mixed Voltage Support in a Bank
The LatticeECP/EC sysIO buffer is connected to three parallel ratioed input buffers. These three parallel buffers are
connected to V
olds for 3.3V (V
a pin-by-pin basis, rather than tracking it with V
inputs and is independent of the bank V
1.2V and 3.3V ratioed input buffers with fixed thresholds, as well as 2.5V ratioed inputs with tracking thresholds.
Prior to device configuration, the ratioed input thresholds always track the bank V
after configuration. Output standards within a bank are always set by V
that the user can mix in the same bank.
Table 7-2. Mixed Voltage Support
V
1.2V
1.5V
1.8V
2.5V
3.3V
CCIO
REF2.
1.2V
Yes
Yes
Yes
Yes
Yes
CCIO,
CCAUX
For more information on the DQS transition detect logic and its implementation please refer to
V
) and 1.2V (V
CCAUX
1.5V
Yes
Input sysIO Standards
and to V
1.8V
Yes
CC
CC
) inputs. This allows the input threshold for ratioed buffers to be assigned on
CCIO
giving support for thresholds that track with V
2.5V
Yes
Yes
Yes
Yes
Yes
voltage. For example, if the bank V
CCIO.
This option is available for all 1.2V, 2.5V and 3.3V ratioed
3.3V
Yes
Yes
Yes
Yes
Yes
7-4
1.2V
Yes
LatticeECP/EC sysIO Usage Guide
CCIO.
1.5V
Yes
Output sysIO Standards
Table 7-2 shows the sysIO standards
CCIO
CCIO,
is 1.8V, it is possible to have
CCIO
1.8V
Yes
this option only takes effect
as well as fixed thresh-
REF1
2.5V
Yes
it is not avail-
3.3V
Yes