C8051F020DK Silicon Laboratories Inc, C8051F020DK Datasheet - Page 137

• Manufacturer Part Number: C8051F020DK
• Description: DEV KIT FOR F020/F021/F022/F023
• Manufacturer: Silicon Laboratories Inc
• Type: MCUr

Specifications of C8051F020DK

• Contents: Evaluation Board, Power Supply, USB Cables, Adapter and Documentation
• Processor To Be Evaluated: C8051F02x
• Interface Type: USB
• Silicon Manufacturer: Silicon Labs
• Core Architecture: 8051
• Silicon Core Number: C8051F020
• Silicon Family Name: C8051F02x
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• For Use With/related Products: Silicon Laboratories C8051 F020/021/022/023
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 336-1200

Bit7:
Bits6-4:
Bit3:
Bits2-0:
CRYSTAL MODE (Circuit from Figure 14.1, Option 1; XOSCMD = 11x)
RC MODE (Circuit from Figure 14.1, Option 2; XOSCMD = 10x)
C MODE (Circuit from Figure 14.1, Option 3; XOSCMD = 10x)
XTLVLD XOSCMD2 XOSCMD1 XOSCMD0
R/W
Bit7
XTLVLD: Crystal Oscillator Valid Flag
(Valid only when XOSCMD = 11x.)
0: Crystal Oscillator is unused or not yet stable
1: Crystal Oscillator is running and stable
XOSCMD2-0: External Oscillator Mode Bits
00x: Off. XTAL1 pin is grounded internally.
010: System Clock from External CMOS Clock on XTAL1 pin.
011: System Clock from External CMOS Clock on XTAL1 pin divided by 2.
10x: RC/C Oscillator Mode with divide by 2 stage.
110: Crystal Oscillator Mode
111: Crystal Oscillator Mode with divide by 2 stage.
RESERVED. Read = undefined, Write = don't care
XFCN2-0: External Oscillator Frequency Control Bits
000-111:
Choose XFCN value to match the crystal or ceramic resonator frequency.
Choose oscillation frequency range where:
f = 1.23(10
f = frequency of oscillation in MHz
C = capacitor value in pF
R = Pull-up resistor value in k
Choose K Factor (KF) for the oscillation frequency desired:
f = KF / (C * AV+), where
f = frequency of oscillation in MHz
C = capacitor value on XTAL1, XTAL2 pins in pF
AV+ = Analog Power Supply on MCU in volts
XFCN
000
001
010
011
100
101
110
111
R/W
Bit6
Figure 14.3. OSCXCN: External Oscillator Control Register
3
) / (R * C), where
Crystal (XOSCMD = 11x)
2.2 MHz < f  6.7 MHz
720 kHz < f  2.2 MHz
270 kHz < f  720 kHz
R/W
Bit5
95 kHz < f  270 kHz
12 kHz < f  30 kHz
30 kHz < f  95 kHz
f > 6.7 MHz
f < 12 kHz
R/W
Bit4
R/W
Bit3
-
Rev. 1.4
RC (XOSCMD = 10x)
1.6 MHz < f  3.2 MHz
800 kHz < f  1.6 MHz
100 kHz < f  200 kHz
200 kHz < f  400 kHz
400 kHz < f  800 kHz
50 kHz < f  100 kHz
25 kHz < f50 kHz
f < 25 kHz
XFCN2
R/W
Bit2
XFCN1
C8051F020/1/2/3
R/W
Bit1
C (XOSCMD = 10x)
K Factor = 1400
K Factor = 0.44
K Factor = 100
K Factor = 420
K Factor = 1.4
K Factor = 4.4
XFCN0
K Factor = 13
K Factor = 38
R/W
Bit0
SFR Address:
00000000
Reset Value
0xB1
137