MC14060B
CLOCK 11
1
f
2.3R
C
tc tc
if 1 kHz ≤ f ≤ 100 kHz
and 2R < R < 10R
tc
RESET
10 OUT 1
9 OUT 2
tc
S
(f in Hz, R in ohms, C in farads)
R
tc
The formula may vary for other frequencies. Recommended
maximum value for the resistors in 1 MΩ.
R
S
C
tc
Figure 3. Oscillator Circuit Using RC Configuration
TYPICAL RC OSCILLATOR CHARACTERISTICS
100
8.0
4.0
V
DD
= 10 V
50
V
DD
= 15 V
f AS A FUNCTION
OF R
20
10
5
TC
(C = 1000 pF)
(R ≈ 2R
0
)
TC
S
1.0 V
–4.0
–8.0
–12
–16
f AS A FUNCTION
OF C
(R = 56 kΩ)
TC
2
1
5.0 V
(R = 120 k)
S
0.5
0.2
0.1
R
= 56 kΩ
R = 0, f = 10.15 kHz @ V = 10, T =25°C
S DD A
R = 120 kΩ, f = 7.8 kHz @ V = 10 V, T =25°C
S DD A
TC
C = 1000 pF
1.0 k
10 k
100 k
1.0 M
0.1
–55
–25
0
25
50
75
100
125
R , RESISTANCE (OHMS)
TC
T , AMBIENT TEMPERATURE (°C)
A
0.0001
0.001
0.01
C, CAPACITANCE (µF)
Figure 4. RC Oscillator Stability
Figure 5. RC Oscillator Frequency as a
Function of RTC and C
CLOCK
11
500 kHz 32 kHz
Circuit Circuit
Characteristic
Unit
Crystal Characteristics
Resonant Frequency
Equivalent Resistance, R
RESET
10 OUT 1
9
OUT 2
500
1.0
32
6.2
kHz
kΩ
S
18M
External Resistor/Capacitor Values
R
O
R
C
C
47
82
20
750
82
20
kΩ
pF
pF
O
T
C
S
C
T
S
Frequency Stability
Frequency Changes as a
Figure 6. Typical Crystal Oscillator Circuit
Function of V (T = 25 C)
DD
A
V
V
Change from 5.0 V to 10V
Change from 10 V to 15 V
+ 6.0
+ 2.0
+ 2.0 ppm
+ 2.0 ppm
DD
DD
Frequency Change as a Function
of Temperature (V = 10 V)
DD
+ 100
– 160
+ 120 ppm
– 560 ppm
T Change from – 55 C to
+25 C Complete Oscillator
A
(8.)
T Change from + 25 C to
A
(8.)
+125 C Complete Oscillator
8. Complete oscillator includes crystal, capacitors, and resistors.
Figure 7. Typical Data for Crystal Oscillator Circuit
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