AT90PWM316-16SUR Atmel, AT90PWM316-16SUR Datasheet - Page 244

• Manufacturer Part Number: AT90PWM316-16SUR
• Description: MCU AVR 16K FLASH 16MHZ 32-SOIC
• Manufacturer: Atmel
• Series: AVR® 90PWM Lightingr

Specifications of AT90PWM316-16SUR

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 27
• Program Memory Size: 16KB (16K x 8)
• Program Memory Type: FLASH
• Eeprom Size: 512 x 8
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 11x10b; D/A 1x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 105°C
• Package / Case: 32-SOIC (7.5mm Width)
• For Use With: ATSTK600-SOIC - STK600 SOCKET/ADAPTER FOR SOICATAVRMC200 - KIT EVAL FOR AT90PWM3 ASYNCATAVRFBKIT - KIT DEMO BALLAST FOR AT90PWM2
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

21.6.3
21.6.4
244
AT90PWM216/316
Offset Compensation Schemes
ADC Accuracy Definitions
The gain stage has a built-in offset cancellation circuitry that nulls the offset of differential mea-
surements as much as possible. The remaining offset in the analog path can be measured
directly by shortening both differential inputs using the AMPxIS bit with both inputs unconnected.
(See “Amplifier 0 Control and Status register – AMP0CSR” on page 256.
1Control and Status register – AMP1CSR” on page
tracted in software from the measurement results. Using this kind of software based offset
correction, offset on any channel can be reduced below one LSB.
An n-bit single-ended ADC converts a voltage linearly between GND and V
(LSBs). The lowest code is read as 0, and the highest code is read as 2
Several parameters describe the deviation from the ideal behavior:
Figure 21-10. Offset Error
• Offset: The deviation of the first transition (0x000 to 0x001) compared to the ideal transition
• Gain Error: After adjusting for offset, the Gain Error is found as the deviation of the last
(at 0.5 LSB). Ideal value: 0 LSB.
transition (0x3FE to 0x3FF) compared to the ideal transition (at 1.5 LSB below maximum).
Ideal value: 0 LSB
Output Code
Offset
Error
257.). This offset residue can be then sub-
V
REF
Input Voltage
n
-1.
and
Ideal ADC
Actual ADC
REF
See “Amplifier
7710E–AVR–08/10
in 2
n
steps