AT90LS2333-4AI Atmel, AT90LS2333-4AI Datasheet - Page 52

• Manufacturer Part Number: AT90LS2333-4AI
• Description: IC MCU 2K 4MHZ A/D LV IT 32TQFP
• Manufacturer: Atmel
• Series: AVR® 90LSr

Specifications of AT90LS2333-4AI

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 4MHz
• Connectivity: SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 20
• Program Memory Size: 2KB (1K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 128 x 8
• Ram Size: 128 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 6 V
• Data Converters: A/D 6x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 32-TQFP, 32-VQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Analog to Digital Converter
Feature list:
• 10-bit Resolution
• ± 2 LSB Absolute Accuracy
• 0.5 LSB Integral Non-Linearity
• 65 - 260 µs Conversion Time
• Up to 15 kSPS
• 6 Multiplexed Input Channels
• Rail-to-Rail Input Range
• Free Run or Single Conversion Mode
• Interrupt on ADC conversion complete.
• Sleep Mode Noise Canceler
The AT90S2333/4433 features a 10-bit successive approximation ADC. The ADC is connected to a 6-channel Analog Mul-
tiplexer which allows each pin of Port C to be used as an input for the ADC. The ADC contains a Sample and Hold Amplifier
which ensures that the input voltage to the ADC is held at a constant level during conversion. A block diagram of the ADC
is shown in Figure 44.
The ADC has two separate analog supply voltage pins, AVCC and AGND. AGND must be connected to GND, and the volt-
age on AVCC must not differ more than ± 0.3 V from V
connect these pins.
An external reference voltage must be applied to the AREF pin. This voltage must be in the range AGND - AVCC.
Figure 44. Analog to Digital Converter Block Schematic
Operation
The ADC can operate in two modes - Single Conversion and Free Run Mode. In Single Conversion Mode, each conversion
will have to be initiated by the user. In Free Run Mode the ADC is constantly sampling and updating the ADC Data Regis-
ter. The ADFR bit in ADCSR selects between the two available modes.
The ADMUX register selects which one of the six analog input channels to be used as input to the ADC.
52
AT90S/LS2333 and AT90S/LS4433
Reference
External
Voltage
Analog
Inputs
8-BIT DATA BUS
CHANNEL
MUX
6-
+
10-BIT DAC
-
SAMPLE & HOLD
COMPARATOR
ADC MULTIPLEXER
SELECT (ADMUX)
CC
. See the paragraph ADC Noise Canceling Techniques on how to
ADC CTRL & STATUS
ADC CONVERSION
REGISTER (ADCSR)
COMPLETE IRQ
CONVERSION LOGIC
9
ADC DATA REGISTER
(ADCH/ADCL)
0