ST7LITE1xB
13.11 10-BIT ADC CHARACTERISTICS
Subject to general operating condition for VDD, fOSC, and TA unless otherwise specified.
Symbol
Parameter
Conditions
Min
Typ 1)
Max
fADC
VAIN
RAIN
CADC
tSTAB
tADC
ADC clock frequency
Conversion voltage range 2)
External input resistor
Internal sample and hold capacitor
Stabilization time after ADC enable
Conversion time (Sample+Hold)
- Sample capacitor loading time
- Hold conversion time
fCPU=8MHz, fADC=4MHz
VSSA
4
VDDA
10 3)
6
0 4)
3.5
4
10
Analog Part
1
IADC Digital Part
0.2
Figure 110. Typical Application with ADC
VDD
Unit
MHz
V
kΩ
pF
µs
1/fADC
mA
VAIN
RAIN
AINx
VT
0.6V
VT
0.6V
IL
±1μA
10-Bit A/D
Conversion
CADC
6pF
ST72XXX
Notes:
1. Unless otherwise specified, typical data are based on TA=25°C and VDD-VSS=5V. They are given only as design guide-
lines and are not tested.
2. When VDDA and VSSA pins are not available on the pinout, the ADC refers to VDD and VSS.
3. Any added external serial resistor will downgrade the ADC accuracy (especially for resistance greater than 10kΩ). Data
based on characterization results, not tested in production.
4. The stabilization time of the AD converter is masked by the first tLOAD. The first conversion after the enable is then
always valid.
Related application notes:
Understanding and minimizing ADC conversion errors (AN1636)
Software techniques for compensating ST7 ADC errors (AN1711)
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