MB3873 Datasheet, PDF (9/22 Pages) Fujitsu Component Limited. – Multi-Resonance AC/DC Converter IC

MB3873
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Triangular oscillator frequency vs. timing resistor
1000
Ta = +25 °C
VCC = 18 V
100
10
1
10
CT = 100 pF
CT = 220 pF
CT = 470 pF
CT = 1000 pF
CT = 2200 pF
CT = 4700 pF
100
Timing resistor RT (kΩ)
Triangular wave upper and lower limit voltage
vs. timing capacitor
3.4
3.2
3.0
2.8
2.6
2.4
2.2
2.0
1.8
1.6
10
Upper
Lower
100
Ta = +25 °C
VCC = 18 V
RT = 33 kΩ
1000
10000
Timing capacitor CT (pF)
Triangular oscillator frequency vs. timing capacitor
1000
Ta = +25 °C
VCC = 18 V
RT = 33 kΩ
100
10
1
10
100
1000
10000
Timing capacitor CT (pF)
Triangular oscillator frequency vs. FB pin current
1000
800
600
Ta = +25 °C
VCC = 18 V
RT = 33 kΩ
CT = 220 pF
400
200
0
−1200 −1000 −800 −600 −400 −200 0
FB pin current IFB (µA)
Triangular oscillator frequency vs. ambient temperature
130
VCC = 18 V
120
RT = 33 kΩ
CT = 220 pF
110
100
90
80
−50 −25 0 25 50 75 100 125
Ambient temperature Ta ( °C)
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