MB3759-P Fujitsu Microelectronics, Inc., MB3759-P Datasheet - Page 19

• Manufacturer Part Number: MB3759-P
• Description: Pulse-width-modulation Control Circuit Push-pull/single-ended Output Mode
• Manufacturer: Fujitsu Microelectronics, Inc.

5. Example Power Supply Voltage Supply Circuit
(1) Supplied via a Zener diode
(2) Supplied via a three-terminal regulator
6. Example Protection Circuit for Output Transistor
(1) Protect the output transistor from the parasitic effect by using a Schottky barrier diode.
Due to its monolithic IC characteristics, applying a negative voltage greater than the diode voltage ( : = 0.5 V) to
the substrate (pin 7) of the MB3759 causes a parasitic effect in the IC which can result in misoperation.
Accordingly, the following measures are required if driving a transformer or similar directly from the output
transistor of the IC.
V
IN
C
R
V
CC
= V
AC
V
Z
Z
MB3759
V
CC
11
10
8
9
Three-terminal
regulator
SBD
MB3759
V
CC
V
IN
V
CC
MB3759
V
= V
CC
IN
V
Z
V
Z
MB3759
19