AT83EB5114 Atmel Corporation, AT83EB5114 Datasheet - Page 61

• Manufacturer Part Number: AT83EB5114
• Manufacturer: Atmel Corporation

Specifications of AT83EB5114

• Max. Operating Frequency: 24 MHz
• Cpu: 8051-12C
• Max I/o Pins: 11
• Adc Channels: 6
• Adc Resolution (bits): 10
• Adc Speed (ksps): 50
• Sram (kbytes): 0.25
• Eeprom (bytes): 256
• Operating Voltage (vcc): 3.0 to 3.6
• Timers: 4
• Mask Rom (kbytes): 4
• Watchdog: Yes

ADC Standby Mode
Voltage Reference
IT ADC Management
4311C–8051–02/08
Figure 29. A/D Converter clock
The conversion frequency CONV_CK is derived from the oscillator frequency with the
following formulas:
F
and
F
F
Some examples can be found on table below:
When the ADC is not used, it is possible to set it in standby mode by clearing bit ADEN
in ADCON register.
The voltage reference can be either internal or external.
As input, the V
When the voltage reference is active, the V
used for the A/D and for any other application requiring a voltage independent from the
power supply. Voltage typical value is 2.4 volt (See “DC Parameters for A/D Converter”
on page 88.)
An interrupt end-of-conversion will occur when the bit ADEOC is activated and the bit
EADC is set. For re-arming the interrupt the bit ADEOC must be cleared by software.
Figure 30. ADC Interrupt Structure
CkAdc
CONV_CK
CONV_CK
F
MHz
OscOut
16
16
= F
= F
CKADC
= F
= F
OscOut
OscOut
ADEOC
ADCON.4
CkAdc
CkAdc
REF
/ (32 - 2*CKRL), if X2=0
X2
/ (2*PRS), if PRS > 0
/ 256, if PRS = 0
pin is used to enter the voltage reference for the A/D conversion.
0
1
, if X2=1
/ 2
CKRL
NA
F
Prescaler PRS
F
Mhz
CkAdc
EADC
16
8
IE0.6
REF
pin is an output. This voltage can be
PRSw
CONV_CK
12
32
ADCI
F
CONV_CK
khz
333
250
Converter
A/D
Conversion
time µs
33
44
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