nRF24E2 Nordic VLSI, nRF24E2 Datasheet - Page 35

• Manufacturer Part Number: nRF24E2
• Description: Single Chip RF Transmitter + MCU + ADC NRF2402 2.4GHz RF Transmitter
• Manufacturer: Nordic VLSI

PRODUCT SPECIFICATION
SUPPLY
R1
VDD
AREF
R2
AIN0
R3
AIN1
Figure 5-2 Typical use of A/D with 2 ratiometric inputs
When EXTREF (ADCCON.4) is set to 0 and ADCSEL (ADCCON.3-0) selects an
input AIN
(i.e. AIN
to AIN
), the result in ADCDATA is directly proportional to the
i
0
7
ratio between the voltage on the selected input, and the internal bandgap reference
(nominally 1.22V).
**N
if single ended input : AIN
voltage = 1.22 V * ADCDATA / 2
i
**(N-1)
**N
if differential input : (AIN
- AIN
) voltage = 1.22 V * (ADCDATA -2
) / 2
i
0
Where N is the number of bits set in ADCRES (ADCSTATIC.1-0) and ADCDATA is
the result bits in ADCDATAH (and ADCDATAL if N > 8).
This mode of operation is normally selected for sources where the voltage is not
depending on the supply voltage.
When ADCSEL (ADCCON.3-0) is set to 8, the ADC will use the internal bandgap
reference (nominally 1.22V), and the input is 1/3 of the voltage on the VDD pins. The
result in ADCDATA is thus directly proportional to the VDD voltage.
VDD voltage = 3.66 V * ADCDATA / 2**N
Where N is the number of bits set in ADCRES (ADCSTATIC.1-0) and ADCDATA is
the result bits in ADCDATAH (and ADCDATAL if N > 8).
Nordic VLSI ASA - Vestre Rosten 81, N-7075 Tiller, Norway - Phone [phone] - Fax [phone]
Revision: 1.0
August 2003
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