1.2.6. Power supplies

The IM-LT3 requires two voltage sources:


Power supply for expansion circuitry


Power supply for FPGA and interface circuits.

A 1.5V DC supply is derived from the 5V supply by an on-board switching regulator to supply the FPGA core voltage.

The voltages can be supplied by one of:

Screw terminals on the IM-LT3

External 5V and 3.3V power supplies can be connected to the screw terminals if the IM-LT3 is used without an Integrator/CP baseboard.

Integrator/CP baseboard

If the IM-LT3 is fitted to an Integrator/CP, the 5V and 3.3V supplies are sourced from the regulators on the CP. Connect an external power supply to the Integrator/CP only.


Attach the power supply to the lowest board in the stack that has a power connector.

Do not use the power connections on the IM-LT3 if the Interface Module is fitted to an Integrator/CP.

Tile header HDRY and HDRX have an option for some of the interface signals to operate at a different signal level than the 3.3V default. The VDDIO_Y and VDDIO_X supplies are normally sourced from a Logic Tile or Core Tile attached to the IM-LT3. Jumper options allow the supplies for these signals to be sourced from 3.3V, see Voltage on header pins for details.

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