viper100bsp STMicroelectronics, viper100bsp Datasheet - Page 8

• Manufacturer Part Number: viper100bsp
• Description: Smps Primary I.c.
• Manufacturer: STMicroelectronics

VIPER100B/BSP
8/20
Figure 9: Oscillator
Ct
Rt
OSC
1,000
VDD
500
300
200
100
0.9
0.8
0.7
0.6
0.5
50
30
1
1
1
Ct = 1.5 nF
Ct = 2.7 nF
Ct = 4.7 nF
Ct = 10 nF
2
2
Oscillator frequency vs Rt and Ct
FC00050
Maximum duty cycle vs Rt
3
3
CLK
5
5
Rt (k )
Rt (k )
10
10
For R
F
D
Recommended D
100KHz: > 80%
200KHz: > 70%
SW
MAX
20
20
T
R
> 1.2 K :
1
FC00030
FC00030
2.3
FC00040
T
30
C
30
T
R
T
D
550
MAX
150
50
50
MAX
values: