C8051F340-GQR Silicon Laboratories Inc, C8051F340-GQR Datasheet - Page 137

• Manufacturer Part Number: C8051F340-GQR
• Description: MCU 8-Bit C8051F34x 8051 CISC 64KB Flash 3.3V/5V 48-Pin TQFP T/R
• Manufacturer: Silicon Laboratories Inc

Specifications of C8051F340-GQR

• Package: 48TQFP
• Device Core: 8051
• Family Name: C8051F34x
• Maximum Speed: 48 MHz
• Operating Supply Voltage: 3.3|5 V
• Data Bus Width: 8 Bit
• Number Of Programmable I/os: 40
• Interface Type: I2C/SMBus/SPI/UART/USB
• On-chip Adc: 17-chx10-bit
• Number Of Timers: 4
• Ram Size: 4.25 KB
• Program Memory Size: 64 KB
• Program Memory Type: Flash
• Operating Temperature: -40 to 85 °C

Bit7:
Bits6–4: XOSCMD2–0: External Oscillator Mode Bits.
Bit3:
Bits2–0: XFCN2–0: External Oscillator Frequency Control Bits.
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
Bit7
R
XTLVLD: Crystal Oscillator Valid Flag.
(Read only when XOSCMD = 11x.)
0: Crystal Oscillator is unused or not yet stable.
1: Crystal Oscillator is running and stable.
00x: External Oscillator circuit off.
010: External CMOS Clock Mode.
011: External CMOS Clock Mode with divide by 2 stage.
100: RC Oscillator Mode.
101: Capacitor Oscillator Mode.
110: Crystal Oscillator Mode.
111: Crystal Oscillator Mode with divide by 2 stage.
RESERVED. Read = 0, Write = don't care.
000-111: See table below:
Choose XFCN value to match crystal or resonator frequency.
Choose XFCN value to match frequency range:
f = 1.23(10
f = frequency of clock 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 x V
f = frequency of clock in MHz
C = capacitor value the XTAL2 pin in pF
V
XFCN Crystal (XOSCMD = 11x) RC (XOSCMD = 10x)
DD
000
001
010
100
101
011
110
111
SFR Definition 14.4. OSCXCN: External Oscillator Control
= Power Supply on MCU in volts
R/W
Bit6
590 kHz  f  1.5 MHz
225 kHz  f  590 kHz
10 MHz  f  30 MHz
3
84 kHz  f  225 kHz
1.5 MHz  f  4 MHz
4 MHz  f  10 MHz
) / (R x C) , where
32 kHz  f  84kHz
DD
R/W
f  32 kHz
Bit5
) , where
C8051F340/1/2/3/4/5/6/7/8/9/A/B/C/D
R/W
Bit4
1.6 MHz  f  3.2 MHz
100 kHz  f  200 kHz
200 kHz  f  400 kHz
400 kHz  f  800 kHz
800 kHz  f  1.6 MHz
50 kHz  f  100 kHz
Rev. 1.3
25 kHz  f  50 kHz
Bit3
R
-
f  25 kHz
XFCN2
R/W
Bit2
XFCN1
C (XOSCMD = 10x)
R/W
Bit1
K Factor = 1590
K Factor = 0.87
K Factor = 180
K Factor = 664
K Factor = 2.6
K Factor = 7.7
K Factor = 22
K Factor = 65
XFCN0
R/W
Bit0
SFR Address:
00000000
Reset Value
0xB1
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