PIC16F874-04/PQ Microchip Technology, PIC16F874-04/PQ Datasheet - Page 120

• Manufacturer Part Number: PIC16F874-04/PQ
• Description: IC MCU FLASH 4KX14 EE 44MQFP
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F874-04/PQ

• Core Size: 8-Bit
• Program Memory Size: 7KB (4K x 14)
• Oscillator Type: External
• Core Processor: PIC
• Speed: 4MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 33
• Program Memory Type: FLASH
• Eeprom Size: 128 x 8
• Ram Size: 192 x 8
• Voltage - Supply (vcc/vdd): 4 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 44-MQFP, 44-PQFP
• Controller Family/series: PIC16F
• No. Of I/o's: 33
• Eeprom Memory Size: 128Byte
• Ram Memory Size: 192Byte
• Cpu Speed: 4MHz
• Processor Series: PIC16F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 192 B
• Interface Type: MSSP, PSP, USART
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 33
• Number Of Timers: 3 bit
• Operating Supply Voltage: 2 V to 5.5 V
• Maximum Operating Temperature: + 70 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: 0 C
• On-chip Adc: 8
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

PICmicro MID-RANGE MCU FAMILY
7.11
DS31007A-page 7-8
Design Tips
Question 1:
Answer 1:
There are a few possibilities, but the most likely is that you did not exactly follow the write
sequence as shown in
are disabled during this sequence.
Question 2:
Answer 2:
The data will only change when a Data EEPROM write occurs. Inadvertent writes may occur
when the device is in a brown-out condition (out of operating specification) and the device is not
being forced to the reset state. During a brown-out, either the internal brown-out circuitry should
be enabled (when available) or external circuitry should be used to reset the PICmicro MCU to
ensure that no data EEPROM writes occur when the device is out of the valid operating range.
Why do the data EEPROM locations not contain the data that I wrote?
Why is the data in the data EEPROM is getting corrupted?
Example
7-2. If you are using this code segment ensure that all interrupts
1997 Microchip Technology Inc.