C8051F829-GS Silicon Laboratories Inc, C8051F829-GS Datasheet - Page 136

• Manufacturer Part Number: C8051F829-GS
• Description: IC MCU 8BIT 8KB FLASH 16SOIC
• Manufacturer: Silicon Laboratories Inc
• Series: C8051F82xr

Specifications of C8051F829-GS

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 25MHz
• Connectivity: SMBus (2-Wire/I²C), SPI, UART/USART
• Peripherals: POR, PWM, WDT
• Number Of I /o: 13
• Program Memory Size: 8KB (8K x 8)
• Program Memory Type: FLASH
• Ram Size: 256 x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 3.6 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 16-SOIC (3.9mm Width)
• Processor Series: C8051F8x
• Core: 8051
• Data Bus Width: 16 bit
• Data Ram Size: 256 B
• Interface Type: I2C, SPI, UART
• Maximum Clock Frequency: 25 MHz
• Number Of Programmable I/os: 13
• Number Of Timers: 3
• Operating Supply Voltage: 1.8 V to 3.6 V
• Maximum Operating Temperature: + 125 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: PK51, CA51, A51, ULINK2
• Development Tools By Supplier: C8051F800DK
• Minimum Operating Temperature: - 55 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Data Converters: -
• Lead Free Status / Rohs Status: Details
• Other names: 336-1809-5

C8051F80x-83x
22.3.2. External RC Example
If an RC network is used as an external oscillator source for the MCU, the circuit should be configured as
shown in Figure 22.1, Option 2. The capacitor should be no greater than 100 pF; however for very small
capacitors, the total capacitance may be dominated by parasitic capacitance in the PCB layout. To deter-
mine the required External Oscillator Frequency Control value (XFCN) in the OSCXCN Register, first
select the RC network value to produce the desired frequency of oscillation, according to Equation 22.1,
where f = the frequency of oscillation in MHz, C = the capacitor value in pF, and R = the pull-up resistor
value in k.
For example: If the frequency desired is 100 kHz, let R = 246 k and C = 50 pF:
f = 1.23( 10
Referring to the table in SFR Definition 22.4, the required XFCN setting is 010b.
136
Figure 22.2. External 32.768 kHz Quartz Crystal Oscillator Connection Diagram
3
) / RC = 1.23 ( 10
22pF*
* Capacitor values depend on
Equation 22.1. RC Mode Oscillator Frequency
crystal specifications
3
) / [ 246 x 50 ] = 0.1 MHz = 100 kHz
32.768 kHz
10M
f
=
1.23 10
Rev. 1.0

22pF*
3


R C

XTAL1
XTAL2
