PIC16F872-I/SS Microchip Technology, PIC16F872-I/SS Datasheet - Page 397

• Manufacturer Part Number: PIC16F872-I/SS
• Description: IC MCU FLASH 2KX14 EE 28SSOP
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F872-I/SS

• Core Size: 8-Bit
• Program Memory Size: 3.5KB (2K x 14)
• Core Processor: PIC
• Speed: 20MHz
• Connectivity: I²C, SPI
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 22
• Program Memory Type: FLASH
• Eeprom Size: 64 x 8
• Ram Size: 128 x 8
• Voltage - Supply (vcc/vdd): 4 V ~ 5.5 V
• Data Converters: A/D 5x10b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-SSOP
• Controller Family/series: PIC16F
• No. Of I/o's: 22
• Eeprom Memory Size: 64Byte
• Ram Memory Size: 128Byte
• Cpu Speed: 20MHz
• No. Of Timers: 3
• Processor Series: PIC16F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 128 B
• Interface Type: I2C, SPI, SSP
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 22
• Number Of Timers: 3 bit
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: 52715-96, 52716-328, 52717-734
• Development Tools By Supplier: PG164130, DV164035, DV244005, DV164005, PG164120, ICE2000, DM163022
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: AC164307 - MODULE SKT FOR PM3 28SSOPAC164020 - MODULE SKT PROMATEII 44TQFPXLT28SS-1 - SOCKET TRANSITION ICE 28SSOP
• Lead Free Status / Rohs Status: Details

21.9
21.10
1997 Microchip Technology Inc.
A/D Accuracy/Error
Effects of a RESET
In systems where the device frequency is low, use of the A/D RC clock is preferred. At moderate
to high frequencies, T
The absolute accuracy specified for the A/D converter includes the sum of all contributions for
quantization error, integral error, differential error, full scale error, offset error, and monotonicity.
It is defined as the maximum deviation from an actual transition versus an ideal transition for any
code. The absolute error of the A/D converter is specified at < 1 LSb for V
device’s specified operating range). However, the accuracy of the A/D converter will degrade as
V
For a given range of analog inputs, the output digital code will be the same. This is due to the
quantization of the analog input to a digital code. Quantization error is typically
inherent in the analog to digital conversion process. The only way to reduce quantization error is
to increase the resolution of the A/D converter.
Offset error measures the first actual transition of a code versus the first ideal transition of a code.
Offset error shifts the entire transfer function. Offset error can be calibrated out of a system or
introduced into a system through the interaction of the total leakage current and source imped-
ance at the analog input.
Gain error measures the maximum deviation of the last actual transition and the last ideal tran-
sition adjusted for offset error. This error appears as a change in slope of the transfer function.
The difference in gain error to full scale error is that full scale does not take offset error into
account. Gain error can be calibrated out in software.
Linearity error refers to the uniformity of the code changes. Linearity errors cannot be calibrated
out of the system. Integral non-linearity error measures the actual code transition versus the ideal
code transition adjusted by the gain error for each code.
Differential non-linearity measures the maximum actual code width versus the ideal code width.
This measure is unadjusted.
The maximum pin leakage current is specified in the Device Data Sheet electrical specification
parameter
In systems where the device frequency is low, use of the A/D RC clock is preferred. At moderate
to high frequencies, T
minimum and should be minimized to reduce inaccuracies due to noise and sampling capacitor
bleed off.
In systems where the device will enter SLEEP mode after the start of the A/D conversion, the RC
clock source selection is required. In this mode, the digital noise from the modules in SLEEP are
stopped. This method gives high accuracy.
A device reset forces all registers to their reset state. This forces the A/D module to be turned off,
and any conversion is aborted. The value that is in the ADRES register is not modified for a
Power-on Reset. The ADRES register will contain unknown data after a Power-on Reset.
DD
diverges from V
D060.
Section 21. 8-bit A/D Converter
REF
AD
AD
.
should be derived from the device oscillator.
should be derived from the device oscillator. T
AD
DS31021A-page 21-13
DD
must not violate the
= V
1/2 LSb and is
REF
(over the
21