PIC16F876A-I/SS Microchip Technology, PIC16F876A-I/SS Datasheet - Page 456

• Manufacturer Part Number: PIC16F876A-I/SS
• Description: IC MCU FLASH 8KX14 EE 28SSOP
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F876A-I/SS

• Core Size: 8-Bit
• Program Memory Size: 14KB (8K x 14)
• Core Processor: PIC
• Speed: 20MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 22
• Program Memory Type: FLASH
• Eeprom Size: 256 x 8
• Ram Size: 368 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: 256Byte
• Ram Memory Size: 368Byte
• Cpu Speed: 20MHz
• No. Of Timers: 3
• Processor Series: PIC16F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 368 B
• Interface Type: I2C, SPI, USART
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 22
• Number Of Timers: 1 x 16 bit
• Operating Supply Voltage: 2 V to 5.5 V
• 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, DV164120
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 5 bit
• Data Rom Size: 256 B
• Height: 1.75 mm
• Length: 10.2 mm
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 4 V
• Width: 5.3 mm
• 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
• Other names: PIC16F876AI/SS

PICmicro MID-RANGE MCU FAMILY
24.6
DS31024A-page 24-14
Design Tips
Question 1:
Answer 1:
Polypropylene film capacitor is a good trade-off between cost, availability and performance
Question 2:
Answer 2:
A source is:
Southern Electronics Company
Telephone: [phone]
Question 3:
Answer 3:
That table is meant to be a good starting point, but does not include variation that is the result of
the device not operating at exactly 4 MHz; tolerance of the external capacitor and variations of
the Programmable Current Source, due to process and application temperature.
A conversion on the Bandgap Reference can be used to judge how to adjust the Programmable
Current Source Output to ensure proper A/D full scale conversions. Example code (routine
ad_optimize, in P14_RV10.ASM) for this adjustment is available with the PICDEM-14A Demo
Board, and may be also available on the Microchip web site.
Question 4:
Answer 4:
This may be caused by self heating of the DIE. Self heating of the DIE may be caused by a few
things, including:
• I/O sinking and/or sourcing significant amount of current
• Power dissipation of the device running
• Package type due to junction to ambient temperature coefficient of package
For best results the power dissipation should be kept low. Calibration is performed with the device
in a low power state.
Question 5:
Answer 5:
The high current components on your board may cause the ground potential difference across
the ground trace or ground plane. To minimize this effect, you should employ two system grounds
on the application board. The first ground, analog ground, used for the reference analog signals
(Slope A/D external capacitor ground, Resistor Divider ground, and etc.). No high current nor any
digital power returns should go through this analog ground system.
The second ground, digital ground, is used for all other digital logic in the system. The applica-
tion’s digital logic will inject noise onto this ground. Proper grounding techniques should be used
to minimize this noise.
These two grounds are connected at the PICmicro’s ground pin. Ideally the two grounds are
implemented using separate ground planes. In most cases, this can still be implemented on a
two layer board. One layer is used for both ground systems, where the two planes are separated
by a gap. The second layer is used as the trace layer.
(remember the PIC14C000 can operate in sleep mode)
What are some recommended Capacitor types?
Can you suggest some sources for Capacitors
I used the recommended capacitor and Programmable Current Source from
Table
I am using the PIC14C000 which also has the on-chip Temperature sensor.
The sensor results seem to be a little high.
My A/D conversion results seem affected by the operation of high current
components on my board. What can I do to minimize this?
24-2, and my A/D input range does not match.
1997 Microchip Technology Inc.