Datasheet

8/23
VIPer50/SP - VIPer50A/ASP
Figure 9: Oscillator
1
Rt
Ct
OSC
VDD
~360Ω
CLK
FC00050
1 2 3 5 10 20 30 50
30
50
100
200
300
500
1,000
Rt (k
Ω
)
Frequency (kHz)
Oscillator frequency vs Rt and Ct
Ct = 1.5 nF
Ct = 2.7 nF
Ct = 4.7 nF
Ct = 10 nF
FC00030FC00030
For R
t
>1.2KΩ
and
C
t
≥ 15nF if F
SW
≤ 40KHz
F
SW
2.3
R
t
C
t
------------
1
550
R
t
150
–
----------------------
–


⋅
=
C
t
Fsw
40kHz
15nF
22nF
Forbidden area
Forbidden area
Ct(nF) =
Fsw(kHz)
880