AT90CAN128-16AE ATMEL Corporation, AT90CAN128-16AE Datasheet - Page 275

• Manufacturer Part Number: AT90CAN128-16AE
• Description: 8-bit Avr Microcontroller With 128K Bytes of Isp Flash And CAN Controller.flash (Kbytes) 128 Vcc (V) 2.7-5.5 EEPROM (Kbytes) 4 SRAM (bytes) 4K CAN (mess. Obj.) 15
• Manufacturer: ATMEL Corporation

ADC Conversion Result
4250C–CAN–03/04
After the conversion is complete (ADIF is high), the conversion result can be found in
the ADC Result Registers (ADCL, ADCH).
For single ended conversion, the result is:
where V
ence (see Table 100 on page 277 and Table 101 on page 278). 0x000 represents
analog ground, and 0x3FF represents the selected reference voltage minus one LSB.
If differential channels are used, the result is:
where V
input pin, GAIN the selected gain factor and V
result is presented in two’s complement form, from 0x200 (-512d) through 0x1FF
(+511d). Note that if the user wants to perform a quick polarity check of the result, it is
sufficient to read the MSB of the result (ADC9 in ADCH). If the bit is one, the result is
negative, and if this bit is zero, the result is positive. Figure 137 shows the decoding of
the differential input range.
Table 82 shows the resulting output codes if the differential input channel pair (ADCn -
ADCm) is selected with a reference voltage of V
Figure 137. Differential Measurement Range
- V
REF
IN
POS
is the voltage on the selected input pin and V
is the voltage on the positive input pin, V
A D C
Output Code
0x3FF
A D C
=
0x1FF
0x000
0x200
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
V
=
P O S
0
V
- - - - - - - - - - - - - - - - - - - - - - - - - -
I N 1023
V
–
R E F
V
N E G
V
R E F
REF
REF
G A I N
the selected voltage reference. The
.
NEG
REF
512
the voltage on the negative
the selected voltage refer-
AT90CAN128
V
REF
Differential Input
Voltage (Volts)
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