Answers Database

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FPGA/CPLD: Do FPGA and CPLD inputs have Hysteresis?

Record #2386

Problem Title:
FPGA/CPLD: Do FPGA and CPLD inputs have Hysteresis?


Problem Description:
keywords: hysteresis, input

Urgency: Standard

General Description:

Urgency: Standard

Keywords: FPGA, CPLD, hysteresis

Description

FGPA inputs do have about 200 ~ 300 mV of hysteresis, but this
is usually neglected in the presence of any groundbounce. CPLD (xc9500) inputs h
ave ~100mV of hysteresis.


Solution 1:

See page 13-15 of Programmable Logic Data Book 1996 for more
information.



End of Record #2386

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