C8051F005DK Silicon Laboratories Inc, C8051F005DK Datasheet - Page 99

• Manufacturer Part Number: C8051F005DK
• Description: DEV KIT FOR F005/006/007
• Manufacturer: Silicon Laboratories Inc
• Type: MCUr

Specifications of C8051F005DK

• Contents: Evaluation Board, Power Supply, USB Cables, Adapter and Documentation
• Processor To Be Evaluated: C8051F01x
• Interface Type: USB
• Silicon Manufacturer: Silicon Labs
• Core Architecture: 8051
• Silicon Core Number: C8051F005
• Silicon Family Name: C8051F00x
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• For Use With/related Products: Silicon Laboratories C8051 F005/006/007
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 336-1188

14. OSCILLATOR
Each MCU includes an internal oscillator and an external oscillator drive circuit, either of which can generate the
system clock. The MCUs boot from the internal oscillator after any reset. The internal oscillator starts up instantly.
It can be enabled/disabled and its frequency can be changed using the Internal Oscillator Control Register
(OSCICN) as shown in Figure 14.2. The internal oscillator’s electrical specifications are given in Table 14.1.
Both oscillators are disabled when the /RST pin is held low. The MCUs can run from the internal oscillator or
external oscillator, and switch between the two at will using the CLKSL bit in the OSCICN Register. The external
oscillator requires an external resonator, parallel-mode crystal, capacitor, or RC network connected to the
XTAL1/XTAL2 pins (see Figure 14.1). The oscillator circuit must be configured for one of these sources in the
OSCXCN register. An external CMOS clock can also provide the system clock via overdriving the XTAL1 pin.
The XTAL1 and XTAL2 pins are 3.6V (not 5V) tolerant. The external oscillator can be left enabled and running
even when the MCU has switched to using the internal oscillator.
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C8051F000/1/2/5/6/7
C8051F010/1/2/5/6/7
opt. 4
XTAL1
opt. 3
XTAL1
XTAL2
AV+
opt. 2
XTAL1
opt. 1
XTAL1
XTAL2
AGND
Figure 14.1. Oscillator Diagram
VDD
AV+
Circuit
Input
OSCXCN
Internal Clock
OSCICN
Generator
EN
OSC
Rev. 1.7
SYSCLK