C8051F311 Silicon Laboratories Inc, C8051F311 Datasheet - Page 125

• Manufacturer Part Number: C8051F311
• Description: IC 8051 MCU 16K FLASH 28MLP
• Manufacturer: Silicon Laboratories Inc
• Series: C8051F31xr

Specifications of C8051F311

• 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: 25
• Program Memory Size: 16KB (16K 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 17x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-VQFN Exposed Pad, 28-HVQFN, 28-SQFN, 28-DHVQFN
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -

Bit7:
Bits6–4: XOSCMD2-0: External Oscillator Mode Bits.
Bit3:
Bits2–0: XFCN2-0: External Oscillator Frequency Control Bits.
CRYSTAL MODE (Circuit from Figure 12.1, Option 1; XOSCMD = 11x)
RC MODE (Circuit from Figure 12.1, Option 2; XOSCMD = 10x)
C MODE (Circuit from Figure 12.1, 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 frequency.
Choose XFCN value to match frequency range:
f = 1.23(10
f = frequency of clock in MHz
C = capacitor value in pF
R = Pullup 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
DD
XFCN
SFR Definition 12.4. OSCXCN: External Oscillator Control
000
001
010
100
101
011
110
111
= Power Supply on MCU in volts
R/W
Bit6
3
) / (R x C), where
Crystal (XOSCMD = 11x)
DD
225 kHz  f 590 kHz
590 kHz  f 1.5 MHz
10 MHz  f 30 MHz
84 kHz  f 225 kHz
1.5 MHz  f 4 MHz
4 MHz  f 10 MHz
32 kHz f 84 kHz
R/W
), where
Bit5
f  32 kHz
R/W
Bit4
Rev. 1.7
Bit3
R
800 kHz f 1.6 MHz
1.6 MHz f 3.2 MHz
100 kHz f 200 kHz
200 kHz f 400 kHz
400 kHz f 800 kHz
RC (XOSCMD = 10x)
50 kHz f 100 kHz
C8051F310/1/2/3/4/5/6/7
25 kHz f 50 kHz
f 25 kHz
XFCN2
R/W
Bit2
XFCN1
R/W
Bit1
C (XOSCMD = 10x)
K Factor = 1590
K Factor = 0.87
K Factor = 180
K Factor = 664
XFCN0
K Factor = 2.6
K Factor = 7.7
K Factor = 22
K Factor = 65
R/W
Bit0
SFR Address:
00000000
Reset Value
0xB1
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