ATtiny48 datasheet(167/266 Pages) ATMEL

Part #	ATtiny48

Description	8-bit Microcontroller with 4/8K Bytes In-System Programmable Flash

PDF	266 Pages

Scroll/Zoom	100%

Manufacturer	ATMEL [ATMEL Corporation]

Direct Link	http://www.atmel.com

Logo

167 / 266 page

167

8008C–AVR–03/09

ATtiny48/88

Where high ADC accuracy is required it is recommended to use ADC Noise Reduction Mode, as

described in Section 17.7 on page 165. This is especially the case when system clock frequency

is above 1 MHz, or when the ADC is used for reading the internal temperature sensor, as

described in Section 17.12 on page 169. A good system design with properly placed, external

bypass capacitors does reduce the need for using ADC Noise Reduction Mode

17.10 ADC Accuracy Definitions

An n-bit single-ended ADC converts a voltage linearly between GND and V

REF in 2

n steps

(LSBs). The lowest code is read as 0, and the highest code is read as 2

n-1.

Several parameters describe the deviation from the ideal behavior:

• Offset: The deviation of the first transition (0x000 to 0x001) compared to the ideal transition

(at 0.5 LSB). Ideal value: 0 LSB.

Figure 17-10. Offset Error

Output Code

VREF Input Voltage

Ideal ADC

Actual ADC

Offset

Error

ATtiny48 Datasheet(PDF) 167 Page - ATMEL Corporation