Holtek HT46R22, Руководство пользователя

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Note that to reduce the quantization error, a 0.5 LSB offset is added to the A/D Converter input. Ex-
cept for the digitized value 0, the subsequent digitized values will change at a point 0.5 LSB below
where they would change without the offset , and the last full scale digitized value will change at a
point 1.5 LSB below the VDD.
The A/D Converter has a maximum of
±
1 LSB Integral Non-Linearity Error which describes the de-
parture from the ideal linear transfer function. For the HT46R47/HT46C47 and HT46R22/HT46C22,
their 9-bit resolution A/D Converter is achieved with 8-bit accuracy while for the HT46R23/HT46C23
and HT46R24/HT46C24, their 10-bit resolution A/D Converter is achieved with 9-bit accuracy.
Chapter 1 Hardware Structure
53
1 F E H
( )
A / D C o n v e r s i o n
R e s u l t
1 F F H
1 F D H
0 3 H
0 2 H
0 1 H
0 . 5 L S B
0 1 2 3 5 0 9 5 1 0 5 1 1 5 1 2
A n a l o g I n p u t V o l t a g e
1 . 5 L S B
V
D D
5 1 2
Ideal A/D Transfer Function
-
HT46R47/HT46C47 and HT46R22/HT46C22
3 F E H
( )
A / D C o n v e r s i o n
R e s u l t
3 F F H
3 F D H
0 3 H
0 2 H
0 1 H
0 . 5 L S B
0 1 2 3
1 0 2 1 1 0 2 2 1 0 2 3 1 0 2 4
A n a l o g I n p u t V o l t a g e
1 . 5 L S B
V
D D
1 0 2 4
Ideal A/D Transfer Function
-
HT46R23/HT46C23 and HT46R24/HT46C24