AT90S4433-8AC Atmel, AT90S4433-8AC Datasheet - Page 67

• Manufacturer Part Number: AT90S4433-8AC
• Description: IC MCU 4K FLSH 8MHZ A/D 32TQFP
• Manufacturer: Atmel
• Series: AVR® 90Sr

Specifications of AT90S4433-8AC

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 8MHz
• Connectivity: SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 20
• Program Memory Size: 4KB (2K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 256 x 8
• Ram Size: 128 x 8
• Voltage - Supply (vcc/vdd): 4 V ~ 6 V
• Data Converters: A/D 6x10b
• Oscillator Type: External
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 32-TQFP, 32-VQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

ADC Noise Canceler
Function
1042H–AVR–04/03
Figure 47. ADC Timing Diagram, Single Conversion
Figure 48. ADC Timing Diagram, Free Run Conversion
The ADC features a Noise Canceler that enables conversion during Idle mode to reduce
noise induced from the CPU core. To make use of this feature, the following procedure
should be used:
1. Make sure that the ADC is enabled and is not busy converting. Single Conver-
2. Enter Idle mode. The ADC will start a conversion once the CPU has been halted.
3. If no other interrupts occur before the ADC conversion completes, the ADC inter-
Cycle Number
ADC Clock
ADSC
ADIF
ADCH
ADCL
sion mode must be selected and the ADC conversion complete interrupt must be
enabled. Thus:
ADEN = 1
ADSC = 0
ADFR = 0
ADIE = 1
rupt will wake up the MCU and execute the ADC conversion complete interrupt
routine.
1
Cycle Number
ADC Clock
ADSC
Hold Strobe
ADIF
ADCH
ADCL
2
MUX and REFS
Update
3
Sample & Hold
4
5
One Conversion
11
6
7
12
One Conversion
8
13
9
Next
Conversion
10
Conversion
1
MSB of Result
LSB of Result
complete
11
2
AT90S/LS4433
12
13
Sign and MSB of Result
LSB of Result
Next Conversion
1
2
MUX and REFS
Update
3
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