MB3789
Sawtooth waveform period vs.
timing capacitance characteristics
(With CT/RT oscillation)
500
VCC1 = 5 V
100
VCC2 = 6 V
50
RT = 39 kΩ
SYNC = GND
Ta = +25°C
10
5
Duty vs. sawtooth wave
frequency characteristics
(With CT/RT oscillation)
100
VCC1 = 5 V
VCC2 = 6 V
80
VDT = 0.6 V
CT = Variable
RT = 39 kΩ
SYNC = GND
60
Ta = −25°C
40
20
2
2 × 10 5 × 10 102 5 × 102 103
5 × 103 104
Timing capacitance CT (pF)
5 × 104
Sawtooth wave frequency vs.
ambient temperature characteristics
(With CT/RT oscillation)
VCC1 = 5 V
VCC2 = 6 V
+10
CT = 1500pF
RT = 39 kΩ
SYNC = GND
+5
0
−5
−10
0
200
500 1 k
5 k 10 k 50 k 100 k
Sawtooth wave frequency f (Hz)
500 k
Sawtooth wave frequency vs.
ambient temperature characteristics
(In external synchronization)
VCC1 = 5 V
+10
VCC2 = 6 V
CT = 1500pF
RT = 43 kΩ
fSYNC = 15.0 kHz
+5
0
−5
10
−40 −20 0 20 40 60 80 100
Ambient temperature Ta (°C)
Gain vs. frequency and phase vs.
frequency characteristics
40
VCC1 = 5 V
180
VCC2 = 6 V
Ta = +25°C
20
Av
90
−40 −20 0 20 40 60 80 100
Ambient temperature Ta (°C)
Measurement circuit for gain-frequency
characteristics and phase-frequency characteristics
2.5 V 2.5 V
4.7 kΩ
4.7 kΩ 240 kΩ
0
−20
−40
1k
φ
10 k
100 k
1M
Frequency f (Hz)
0
−90
−180
10 M
10 µF
IN
4.7 kΩ
4.7 kΩ
Error amp.
OUT
(Continued)
11