C8051F800DK Silicon Laboratories Inc, C8051F800DK Datasheet - Page 49

• Manufacturer Part Number: C8051F800DK
• Description: KIT DEV C8051F800
• Manufacturer: Silicon Laboratories Inc
• Type: MCUr

Specifications of C8051F800DK

• Contents: Board, Cables, CD, Debugger, Power Supply
• Processor To Be Evaluated: C8051F800
• Data Bus Width: 16 bit
• Interface Type: USB
• Operating Supply Voltage: 7 V to 15 V
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• For Use With/related Products: C8051F8xx
• Lead Free Status / Rohs Status: Supplier Unconfirmed
• Other names: 336-1797

8.3.3. Settling Time Requirements
A minimum tracking time is required before each conversion to ensure that an accurate conversion is per-
formed. This tracking time is determined by any series impedance, including the AMUX0 resistance, the
the ADC0 sampling capacitance, and the accuracy required for the conversion. In delayed tracking mode,
three SAR clocks are used for tracking at the start of every conversion. For many applications, these three
SAR clocks will meet the minimum tracking time requirements.
Figure 8.3 shows the equivalent ADC0 input circuit. The required ADC0 settling time for a given settling
accuracy (SA) may be approximated by Equation 8.1. See Table 7.9 for ADC0 minimum settling time
requirements as well as the mux impedance and sampling capacitor values.
Where:
SA is the settling accuracy, given as a fraction of an LSB (for example, 0.25 to settle within 1/4 LSB)
t is the required settling time in seconds
R
n is the ADC resolution in bits (10).
TOTAL
is the sum of the AMUX0 resistance and any external source resistance.
Note: See electrical specification tables for R
Input Pin
Equation 8.1. ADC0 Settling Time Requirements
Figure 8.3. ADC0 Equivalent Input Circuits
t
=
RC
MUX Select
ln
Input


------ -
SA
= R
2
n


MUX

* C
Rev. 1.0
R
R
TOTAL
SAMPLE
MUX
C
SAMPLE
MUX
and C
C
SAMPLE
C8051F80x-83x
SAMPLE
parameters.
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