MC14060B
http://onsemi.com
5
Figure 3. Oscillator Circuit Using RC Configuration
11
RESET
R
S
C
tc
R
tc
10OUT 1 9OUT 2
f [
1
2.3 R
tc
C
tc
if 1 kHz ≤ f ≤ 100 kHz
and 2R
tc
< R
S
< 10R
tc
(f in Hz, R in ohms, C in farads)
The formula may vary for other frequencies. Recommended
maximum value for the resistors in 1 MW.
TYPICAL RC OSCILLATOR CHARACTERISTICS
Figure 4. RC Oscillator Stability Figure 5. RC Oscillator Frequency as a
Function of R
TC
and C
- 8.0
-12
-16
- 4.0
0
4.0
8.0
1251007550250-25-55
T
A
, AMBIENT TEMPERATURE (°C)
FREQUENCY DEVIATION (%)
V
DD
= 15 V
1.0 V
5.0 V
R
TC
= 56 kW
C = 1000 pF
R
S
=0, f=10.15kHz @ V
DD
=10, T
A
=25°C
R
S
=120 kW, f=7.8kHz @ V
DD
=10V, T
A
=25°C
f, OSCILLATOR FREQUENCY (kHz)
100
50
20
10
5
2
1
0.5
0.2
0.1
1.0 k 10 k 100 k 1.0 M
R
TC
, RESISTANCE (OHMS)
0.0001 0.001 0.01 0.1
C, CAPACITANCE (mF)
V
DD
= 10 V
f AS A FUNCTION
OF R
TC
(C = 1000 pF)
(R
S
≈ 2R
TC
)
f AS A FUNCTION
OF C
(R
TC
= 56 kW)
(R
S
= 120 k)
Figure 6. Typical Crystal Oscillator Circuit
CLOCK
11
RESET
9OUT 210OUT 1
18M
R
O
C
S
C
T
Table 2. Typical Data for Crystal Oscillator Circuit
Characteristic
500 kHz
Circuit
32 kHz
Circuit
Unit
Crystal Characteristics
Resonant Frequency
Equivalent Resistance, R
S
500
1.0
32
6.2
kHz
kW
External Resistor/Capacitor Values
R
O
C
T
C
S
47
82
20
750
82
20
kW
pF
pF
Frequency Stability
Frequency Changes as a
Function of V
DD
(T
A
= 25°C)
V
DD
Change from 5.0 V to 10 V
V
DD
Change from 10 V to 15 V
Frequency Change as a Function of
Temperature (V
DD
= 10 V)
T
A
Change from − 55°C to
+25°C Complete Oscillator (Note 6)
T
A
Change from + 25°C to
+ 125°C Complete Oscillator
(Note 6)
+6.0
+2.0
+100
–160
+2.0
+2.0
+120
–560
ppm
ppm
ppm
ppm
6. Complete oscillator includes crystal, capacitors, and resistors.
