Atmel AT89C5132 - Manual (Page 30)

30
4173ES–USB–09/07
AT89C5132
6.3.7 Analog to Digital Converter
6.3.7.1 Definition of Symbols
Table 18. Analog to Digital Converter Timing Symbol Definitions
6.3.7.2 Characteristics
Table 18. Analog to Digital Converter AC Characteristics
V
DD
= 2.7 to 3.3 V, T
A
= -40 to +85 ° C
Notes: 1. AV
DD
= AV
REFP
= 3.0 V, AV
SS
= AV
REFN
= 0 V. ADC is monotonic with no missing code.
2. The differential non-linearity is the difference between the actual step width and the ideal step
width (see Figure 6-20).
3. The integral non-linearity is the peak difference between the center of the actual step and the
ideal transfer curve after appropriate adjustment of gain and offset errors (see Figure 6-20).
4. The offset error is the absolute difference between the straight line which fits the actual trans-
fer curve (after removing of gain error), and the straight line which fits the ideal transfer curve
(see Figure 6-20).
5. The gain error is the relative difference in percent between the straight line which fits the actual
transfer curve (after removing of offset error), and the straight line which fits the ideal transfer
curve (see Figure 6-20).
Signals Conditions
C Clock H High
E Enable (ADEN bit) L Low
S
Start Conversion
(ADSST bit)
Symbol Parameter Min Max Unit
T
CLCL
Clock Period 4 μ s
T
EHSH
Start-up Time 4 μ s
T
SHSL
Conversion Time 11·T
CLCL
μ s
DLe
Differential non-
linearity error
(1)(2)
1 LSB
ILe
Integral non-linearity
errorss
(1)(3)
2 LSB
OSe Offset error (1)(4) 4 LSB
Ge Gain error (1)(5) 4 LSB