C8051F321-GM Silicon Laboratories Inc, C8051F321-GM Datasheet - Page 116

• Manufacturer Part Number: C8051F321-GM
• Description: IC 8051 MCU 16K FLASH 28MLP
• Manufacturer: Silicon Laboratories Inc
• Series: C8051F32xr

Specifications of C8051F321-GM

• Program Memory Type: FLASH
• Program Memory Size: 16KB (16K x 8)
• Package / Case: 28-VQFN Exposed Pad, 28-HVQFN, 28-SQFN, 28-DHVQFN
• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 25MHz
• Connectivity: SMBus (2-Wire/I²C), SPI, UART/USART, USB
• Peripherals: Brown-out Detect/Reset, POR, PWM, Temp Sensor, WDT
• Number Of I /o: 21
• Ram Size: 2.25K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 3.6 V
• Data Converters: A/D 13x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Processor Series: C8051F3x
• Core: 8051
• Data Bus Width: 8 bit
• Data Ram Size: 2.25 KB
• Interface Type: I2C/SMBus/SPI/UART/USB
• Maximum Clock Frequency: 25 MHz
• Number Of Programmable I/os: 21
• Number Of Timers: 4
• Operating Supply Voltage: 2.7 V to 3.6 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: PK51, CA51, A51, ULINK2
• Development Tools By Supplier: C8051F320DK
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 13-ch x 10-bit or 17-ch x 10-bit
• No. Of I/o's: 21
• Ram Memory Size: 1280Byte
• Cpu Speed: 25MHz
• No. Of Timers: 4
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: 336-1480 - DAUGHTER CARD TOOLSTCK C8051F321770-1006 - ISP 4PORT FOR SILABS C8051F MCU336-1449 - ADAPTER PROGRAM TOOLSTICK F321336-1260 - DEV KIT FOR C8051F320/F321
• Eeprom Size: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 336-1261

C8051F320/1
13. Oscillators
C8051F320/1 devices include a programmable internal oscillator, an external oscillator drive circuit, and a
4x Clock Multiplier. The internal oscillator can be enabled/disabled and calibrated using the OSCICN and
OSCICL registers, as shown in Figure 13.1. The system clock (SYSCLK) can be derived from the internal
oscillator, external oscillator circuit, or the 4x Clock Multiplier divided by 2. The USB clock (USBCLK) can
be derived from the internal oscillator, external oscillator, or 4x Clock Multiplier. Oscillator electrical specifi-
cations are given in Table 13.3 on page 125.
13.1. Programmable Internal Oscillator
All C8051F320/1 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
Equation 13.1, where f
internal oscillator period, and OSCICL is a change to the value held in register OSCICL.
116
VDD
Option 2
XTAL2
Option 1
Option 4
10M
XTAL2
Option 3
XTAL2
XTAL1
XTAL2
BASE
is the frequency of the internal oscillator following a reset, T is the change in
Figure 13.1. Oscillator Diagram
OSCICL
Circuit
Input
Programmable
Internal Clock
Generator
OSCXCN
OSC
EN
Rev. 1.4
EXOSC / 2
OSCICN
IOSC
EXOSC
EXOSC
IOSC
CLKMUL
n
Clock Multiplier
x 2
x 2
EXOSC / 2
EXOSC / 3
EXOSC / 4
IOSC / 2
EXOSC
CLKSEL
SYSCLK
USBCLK