MB3817_03 Datasheet, PDF (9/28 Pages) Fujitsu Component Limited. – Switching Regulator Controller

MB3817
10 M
1M
100 k
10 k
1k
1k
Triangular wave frequency vs.
timing resistance
VCC = 6 V
Ta = +25 °C
CT = 150 pF
CT = 1500 pF
CT = 15000 pF
10 k
100 k
1M
Timing resistance RT (Ω)
Triangular wave maximum amplitude voltage vs.
timing capacitance
1.8
VCC = 6 V
1.6
Ta = +25 °C
RT = 6.2 kΩ
1.4
1.2
1.0
0.8
0.6
10
10²
10³
10⁴
10⁵
Timing capacitance CT (pF)
Duty vs. triangular wave frequency
100
Triangular wave cycle vs. timing capacitance
1000
80
60
40
20
0
1k
100
VCC = 6 V
Ta = +25 °C
RT = 6.2 kΩ
10
VDTC = VREF × 0.88
1
10 k
100 k
1M
Triangular wave frequency fOSC (Hz)
10 M
0.1
10
VCC = 6 V
Ta = +25 °C
RT = 6.2 kΩ
10²
10³
10⁴
10⁵
Timing capacitance CT (pF)
10.00
5.00
Frequency stability vs. ambient temperature
VCC = 6 V
fOSC = 500 kHz
(CT = 330 pF, RT = 6.2 kΩ)
0.00
−5.00
−10.00
−60 −40 −20 0
20 40 60
Ambient temperature Ta (°C)
80 100
(Continued)
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