C8051F020/1/2/3
136
Rev. 1.4
Table 14.1. Internal Oscillator Electrical Characteristics
VDD = 2.7V to 3.6V; Ta = -40°C to +85°C
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
Internal Oscillator Frequency
OSCICN.[1:0] = 00
OSCICN.[1:0] = 01
OSCICN.[1:0] = 10
OSCICN.[1:0] = 11
1.5
3.1
6.2
12.3
2
4
8
16
2.4
4.8
9.6
19.2
MHz
Internal Oscillator Current
Consumption (from VDD)
OSCICN.2 = 1
200
A
Figure 14.2. OSCICN: Internal Oscillator Control Register
Bit7:
MSCLKE: Missing Clock Enable Bit
0: Missing Clock Detector Disabled
1: Missing Clock Detector Enabled; reset triggered if clock is missing for more than 100 s
Bits6-5:
UNUSED. Read = 00b, Write = don't care
Bit4:
IFRDY: Internal Oscillator Frequency Ready Flag
0: Internal Oscillator Frequency not running at speed specified by the IFCN bits.
1: Internal Oscillator Frequency running at speed specified by the IFCN bits.
Bit3:
CLKSL: System Clock Source Select Bit
0: Uses Internal Oscillator as System Clock.
1: Uses External Oscillator as System Clock.
Bit2:
IOSCEN: Internal Oscillator Enable Bit
0: Internal Oscillator Disabled
1: Internal Oscillator Enabled
Bits1-0:
IFCN1-0: Internal Oscillator Frequency Control Bits
00: Internal Oscillator typical frequency is 2 MHz.
01: Internal Oscillator typical frequency is 4 MHz.
10: Internal Oscillator typical frequency is 8 MHz.
11: Internal Oscillator typical frequency is 16 MHz.
R/W
Reset Value
MSCLKE
-
IFRDY
CLKSL
IOSCEN
IFCN1
IFCN0
00010100
Bit7
Bit6
Bit5
Bit4
Bit3
Bit2
Bit1
Bit0
SFR Address:
0xB2