C8051F312-GQR Silicon Laboratories Inc, C8051F312-GQR Datasheet - Page 121

• Manufacturer Part Number: C8051F312-GQR
• Description: IC 8051 MCU 8K FLASH 32LQFP
• Manufacturer: Silicon Laboratories Inc
• Series: C8051F31xr

Specifications of C8051F312-GQR

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 25MHz
• Connectivity: SMBus (2-Wire/I²C), SPI, UART/USART
• Peripherals: POR, PWM, Temp Sensor, WDT
• Number Of I /o: 29
• Program Memory Size: 8KB (8K x 8)
• Program Memory Type: FLASH
• Ram Size: 1.25K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 3.6 V
• Data Converters: A/D 21x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 32-LQFP
• For Use With: 336-1445 - ADAPTER PROGRAM TOOLSTICK F310
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

12. Oscillators
C8051F31x devices include a programmable internal oscillator and an external oscillator drive circuit. The
internal oscillator can be enabled/disabled and calibrated using the OSCICN and OSCICL registers, as
shown in Figure 12.1. The system clock can be sourced by the external oscillator circuit, the internal oscil-
lator, or a scaled version of the internal oscillator. The internal oscillator's electrical specifications are given
in Table 12.1 on page 123.
12.1. Programmable Internal Oscillator
All C8051F31x devices include a programmable internal oscillator that defaults as the system clock after a
system reset. The internal oscillator period can be programmed via the OSCICL register as defined by
SFR Definition 12.1 OSCICL is factor calibrated to obtain a 24.5 MHz frequency.
Electrical specifications for the precision internal oscillator are given in Table 12.1 on page 123. Note that
the system clock may be derived from the programmed internal oscillator divided by 1, 2, 4, or 8, as
defined by the IFCN bits in register OSCICN. The divide value defaults to 8 following a reset.
VDD
Option 2
Option 3
XTAL2
XTAL2
Option 1
Option 4
XTAL2
10M
Figure 12.1. Oscillator Diagram
XTAL1
XTAL2
OSCICL
Rev. 1.7
Circuit
Input
Programmable
Internal Clock
Generator
OSCXCN
C8051F310/1/2/3/4/5/6/7
OSC
EN
OSCICN
n
CLKSEL
SYSCLK
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