ATF280F_14 datasheet(73/107 Pages) ATMEL

73 / 107 page

ATF280F [DATASHEET]

7750E

−AERO−05/12

12.

Power Supply Management

12.1

Cold sparing

Cold sparing capability of the IOs allows to be electricaly connected to a bus while its power supply remains in the

range [VSS-300mV/VSS+300mV], this without any risk of damage for the device. Cold-sparing allows a redundant

spare to be electrically connected but unpowered until needed.

For applications requiring high reliability, the capability to use of a redundant device is a key feature. Cold sparing

availability on the ATF280F makes the FPGA especially suitable for high reliability systems.

The cold sparing feature is available for all the IOs:

• All the General Purpose IOs

• All the LVDS IOs

They present an high input impedance when unpowered [VSS-300mV / VSS+300mV] and exhibit a negligible leakage

current if exposed to a non-null input voltage at that time.

12.2

Power sequencing

The ATF280F is based on Atmel ATC18RHA 0.18 µm CMOS process. When the ATF280F needs to be powered

"on/off" while other circuits in the application are still powered, the recommended “power on/off” sequences are:

• power-up

•

First power VCC33 (I/O),

•

Then power VDD18 (Core).

• power-down

•

First unpower VDD18 (Core),

•

Then unpower VCC33 (I/O).

It is also recommended to stop all activity during these phases as a bi-directional could be in an undetermined state

(input or output mode) and create bus contention.

ATF280F Datasheet(PDF) 73 Page - ATMEL Corporation