afs600 Actel Corporation, afs600 Datasheet - Page 124

• Manufacturer Part Number: afs600
• Description: Actel Fusion Programmable System Chips Mixed-signal Family With Optional Arm Support
• Manufacturer: Actel Corporation

Calculating LSBs from a Given Error Budget
For a given prescaler range,
2 -1 1 0
Actel Fusion Programmable System Chips
Formula
Example
LSB count = ± (Input Voltage × Required % error) / (Equivalent voltage per LSB)
Input Voltage = 5 V
Required error margin= 1%
Refer to
Equivalent voltage per LSB = 16mV for a 16V prescaler, with ADC in 10-bit mode
LSB Count = ± (5.0 V × 1%) / (0.016)
LSB Count = ± 3.125
Equivalent voltage per LSB = 8 mV for an 8 V prescaler, with ADC in 10-bit mode
LSB Count = ± (5.0 V × 1%) / (0.008)
LSB Count = ± 6.25
The 8 V prescaler satisfies the calculated LSB count accuracy requirement (see
Table 2-49 on page
2-108.
A d v a n c e d v 1 . 4
Table 2-49 on page
2-108).