bd4729gg-tr ROHM Co. Ltd., bd4729gg-tr Datasheet - Page 5

• Manufacturer Part Number: bd4729gg-tr
• Description: Bipolar Voltage Detector Ics
• Manufacturer: ROHM Co. Ltd.

 Circuit Applications
© 2010 ROHM Co., Ltd. All rights reserved.
BD47□□G series
www.rohm.com
1)
2)
The following is an example of an application circuit using Reset IC for normal power supply detection. BD47□□G
series requires a pull up resistor on the output terminal. The pull up resister value should be decided. As the
application with enough confirmation of power supply level and output current capability. When a capacitor has been
inserted into the output terminal to delay the output time or to remove noise, the output will be slower during starting or
stopping. Please be careful to select the appropriate pull up resistors, output current and capacitor when inserting a
bypass capacitor between input and GND. Please be aware that if an extremely large capacitor is used, the response
time will become excessively slow.
The following shows an example of adding delay time to a reset signal. It is possible to set the delay time using the
capacitor CL and the resistor RL connected to the output terminal as shown below. At VCC start up, CL will be
charged by RL. The CL and RL time constants and the threshold voltage of the Reset terminal determine the charge
delay time. When VCC is decreased, CL is discharged through the Reset IC. The sum of the respective times plus the
delay time of the IC itself becomes the reset signal delay time.
BD47□□G
V
RESET
(=V
CC
OUT
Vref
)
V
V
0V
V
S
OH
OL
+ΔV
V
V
CC
V
GND
V
S
S
5
3
CC
OUT
GND
V
CC
BD47□□G
T
PLH
Fig.13
5/7
4
Fig.12
V
OUT
R
C
L
L
T
PHL
V
Reset Pin
DD
RESET
●●●●●●●●●●●●
●●●●●●●●●●●●
microcontroller
V
GND
DD
T
PLH
CPU
Micro-controller
●
●
●
●
●
●
●
●
●
●
●
Technical Note
2010.04 - Rev.C