Fujitsu MB3788 manual 180

Page 11

MB3788

(Continued)

7. Duty - input oscillating frequency characteristic

8.Gain - frequency characteristic and phase - frequency

characteristic

100

Input waveform

VCC = 6 V

40

°

180

1.9V

TA = +25 C

80

VFB = 1.6 V

1.3V

TA = +25°C

60

20

90

Duty

Gain

Phase

Dtr (%)

40

(dB)

0 φ (deg)

0

20

-20

-90

0

-180

0

5K

10K

50K 100K

500K

1M

-40

Input oscillating frequency (Hz)

1K

10K

100K

1M

5M 10M

f (Hz)

9. Power dissipation - ambient temperature characteristic

1000

Circuit for measuring gain - frequency characteristic and

phase - frequency characteristic

2.5 V

2.5 V

240 kΩ

VCC = 6 V

800

Power

600

4.7 kΩ

4.7 kΩ

dissipation

-

PD (mW)

10 ∝F

out

400

in

-

+

+

Error amplifier

200

4.7 kΩ

4.7 kΩ

0

-20 020

406080 100

Ambient temperature TA (°C)

11

Image 11

Contents Package FeaturesDescription PIN Assignment MB3788Pin No Pin name Descriptions PIN DescriptionMB3788 Block DiagramFunctional Description Low input voltage malfunction fail-safe circuit Timer and latch-type short-circuit protection circuitRecommended Operating Conditions Parameter Symbol Conditions Ratings Unit Min MaxParameter Symbol Conditions Values Unit Min Typ Max Absolute Maximum RatingsParameter Symbol Conditions Value Unit Min Typ Max Electical CharacteristicsPWM TA = +25C Supply voltage VCC 8 12 16 Standard Characteristic Curves180 HOW to SET Output Voltage OFF HOW to SET Output CurrentLatch-Type Short-Circuit Protection Circuit Processing without using SCP Pin Processing Without Using SCP PINBasic Voltage-Drop Type DC/DC Converter Circuit DC/DC Converter a V φ Characteristic Measurement Diagram SCP Inpwm GND Application CircuitPart number Package Remarks Ordering InformationIndex Package DimensionFujitsu Limited