Datasheet

ST6200C/ST6201C/ST6203C
70/100
CLOCK AND TIMING CHARACTERISTICS (Cont’d)
10.5.4 RC Oscillator
The ST6 internal clock can be supplied with an external RC oscillator. Depending on the
R
NET
value, the
accuracy of the frequency is about 20%, so it may not be suitable for some applications.
Notes:
1. Data based on characterization results, not tested in production. These measurements were done with the OSCin pin
unconnected (only soldered on the PCB).
2. R
NET
must have a positive temperature coefficient (ppm/°C), carbon resistors should therefore not be used.
Figure 45. Typical Application with RC Oscillator
Symbol Parameter Conditions Min Typ Max Unit
f
OSC
RC oscillator frequency
1)
4.5V
≤
V
DD
≤
6.0V
R
NET
=22 k
Ω
R
NET
=47 k
Ω
R
NET
=100 k
Ω
R
NET
=220 k
Ω
R
NET
=470 k
Ω
7.2
5.1
3.2
1.8
0.9
8.6
5.7
3.4
1.9
0.95
10
6.5
3.8
2
1.1
MHz
3V
≤
V
DD
≤
3.6V
R
NET
=22 k
Ω
R
NET
=47 k
Ω
R
NET
=100 k
Ω
R
NET
=220 k
Ω
R
NET
=470 k
Ω
3.7
2.8
1.8
1
0.5
4.3
3
1.9
1.1
0.55
4.9
3.3
2
1.2
0.6
R
NET
RC Oscillator external resistor
2)
see Figure 46 & Figure 47 22 870 k
Ω
OSC
IN
OSC
OUT
R
NET
EXTERNAL RC
C
EX
~9pF DISCHARGE
ST62XX
V
DD
V
DD
f
OSC
V
DD
NC
MIRROR
CURRENT
1