MB3821 Datasheet, PDF (9/24 Pages) Fujitsu Component Limited. – 2-ch DC/DC Converter IC With Synchronous Rectifier

MB3821
(Continued)
500
400
Control current vs. control voltage
Ta = +25 °C
VCC = 16 V
SEL = 0 V
300
200
100
0
0
10
20
30
40
50
Control voltage VCTL (V)
Triangular wave upper and lower limit voltage
vs. triangular wave oscillator frequency
2.5
Ta = +25 °C
VCC = 16.0 V
CTL = 5 V
2.0
Upper
1.5
1.0
Lower
0.5
1k
10 k
100 k
1M
Triangular wave oscillator frequency fOSC (Hz)
Triangular wave oscillator frequency
vs. CT capacitance
10 M
1M
VCC = 16 V
CTL = 5 V
SEL = 0 V
RT = 10 kΩ
Select pin current vs. select pin voltage
500
Ta = +25 °C
VCC = 16 V
400
CTL = 5 V
300
200
100
0
0
10
20
30
40
50
Select pin voltage VSEL (V)
Triangular wave upper and lower limit voltage
vs. ambient temperature
2.6
2.4
VCC = 16 V
CTL = 5 V
2.2
SEL = 0 V
2.0
Upper
1.8
1.6
RT = 10 kΩ, CT = 500 pF
1.4
1.2
Lower
1.0
0.8
0.6
−40 −20 0
20 40 60 80 100
Ambient temperature Ta (°C)
1M
100 k
Triangular wave oscillator frequency
vs. CT capacitance
VCC = 16 V
CTL = 5 V
SEL = 5 V
RT = 10 kΩ
100 k
10 k
10 k
1k
1k
10 p
100 p
1n
10 n
CT capacitance (F)
100 n
100
10 p
100 p
1n
10 n
100 n
CT capacitance (F)
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