M1AFS250-FGG256I Actel Corporation, M1AFS250-FGG256I Datasheet - Page 115

• Manufacturer Part Number: M1AFS250-FGG256I
• Description: Actel Fusion Family Of Mixed Signal Fpgas
• Manufacturer: Actel Corporation

Actel Fusion Family of Mixed Signal FPGAs
Terminology
Resolution
Resolution defines the smallest temperature change Fusion Temperature Monitor can resolve. For ADC
configured as 8-bit mode, each LSB represents 4°C, and 1°C per LSB for 10-bit mode. With 12-bit mode,
the Temperature Monitor can still only resolve 1°C due to Temperature Monitor design.
Offset
The Fusion Temperature Monitor has a systematic offset of +5°C, excluding error due board resistance
and ideality factor of the external diode, between the operation range of –40°C to +85°C. For instance,
25°C will be read by the Temperature Monitor as 30°C plus error. The user can remove any offset error
through hardware or software during the calibration routine.
Analog-to-Digital Converter Block
At the heart of the Fusion analog system is a programmable Successive Approximation Register (SAR)
ADC. The ADC can support 8-, 10-, or 12-bit modes of operation. In 12-bit mode, the ADC can resolve
500 ksps. All results are MSB-justified in the ADC. The input to the ADC is a large 32:1 analog input
multiplexer. A simplified block diagram of the Analog Quads, analog input multiplexer, and ADC is shown
in
Figure
2-80. The ADC offers multiple self-calibrating modes to ensure consistent high performance
both at power-up and during runtime.
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