BD52□□G, BD52□□FVE, BD53□□G, BD53□□FVE series
Circuit Applications
1) Examples of a common power supply detection reset circuit
Technical Note
V
DD1
R
L
BD52□□□
C
T
C
L
（Noise-filtering
Capacitor）
）
V
DD2
Application examples of BD52□□G/FVE series (Open
Drain output type) and BD53□□G/FVE series (CMOS
output type) are shown below.
Microcontroller
GND
Fig.18 Open Collector Output Type
CASE1: the power supply of the microcontroller (VDD2)
differs from the power supply of the reset detection
(VDD1).
Use the open drain output type (BD52□□G/FVE) attached
a load resistance (RL) between the output and VDD2. (As
shown Fig.15)
V
DD1
CASE2: the power supply of the microcontroller (VDD1) is
same as the power supply of the reset detection (VDD1).
Use CMOS output type (BD53□□G/FVE) or open drain
output type (BD52□□G/FVE) attached a load resistance
(RL) between the output and Vdd1. (As shown Fig.16)
BD53□□□
C
T
C
L
（Noise-filtering
Capacitor）
Microcontroller
When a capacitance CL for noise filtering is connected to
the VOUT pin (the reset signal input terminal of the
microcontroller), please take into account the waveform of
the rise and fall of the output voltage (VOUT).
GND
Fig.19 CMOS Output Type
2) The following is an example of a circuit application in which an OR connection between two types of detection voltages
resets the microcontroller.
V
DD1
V
DD2
V
DD3
R
L
BD52□□□
NO.1
C
T
C
T
BD52□□□
NO.2
R
ST
microcontroller
GND
Fig.20
When there are many power supplies of the system, power supplies VDD1 and VDD2 are being monitored separately, and it is
necessary to reset the microcomputer, it is possible to use an OR connection on the open drain output type BD52□□G/FVE
series to pull-up to the desired voltage (VDD3) as shown in Fig.17 and make the output “High” voltage matches the power
supply voltage VDD3 of the microcontroller.
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