Rv5vh1, Rv5vh2 – Ricoh RV5VH User Manual
Page 24
RV5VH1
××
/RV5VH2
××
20
V
SEN
D
OUT
RV5VH1
××
/RV5VH2
××
Pull-up
Output Tr.
–
+
Vref
Ra
Rb
Rc
Tr.1
2
8
The VD can operate by the voltage of “V
OUT1
”. The detector threshold and the reset voltage are internally adjusted by
trimmed resistors and the VD monitors V
SEN
pin voltage.
The D
OUT
is Nch-opendrain output and a pull up resistor is necessary.
Oepration Diagram
V
SEN
pin is pulled up to V
OUT1
voltage
• Voltage Detector
A
B
Reset Voltage
Detector Threshold
GND
GND
Output Voltage
1
2
3
4
5
Hysteresis Range
+V
DET
–V
DET
Step
Step 1
Step 2
Step 3
Step 4
Step 5
Comparator(+) Pin
Input Voltage
A
B
B
B
A
Comparator Output
H
L
L
L
H
Tr. 1
OFF
ON
ON
ON
OFF
Output Tr
OFF
ON
Indefinite
ON
OFF
A :
Rb+Rc
×
V
SEN
Ra+Rb+Rc
B :
Rb
×
V
SEN
Ra+Rb+Rc
Step 1. Output Voltage is equal to Pull-up Voltage.
Step 2. When Input voltage (V
SEN
) reaches the state of Vref
≥
V
SEN
×
(Rb
×
Rc)/(Ra+Rb+Rc) at point A, the output of the comparator is reversed. so that the
output voltage becomes to GND.
Step 3. Output VoItage becomes indefinite when Power source Voltage (V
SEN
) is smaller than Minimum Operating VoItage. When the output is pulIed up,
Output becomes pull-up voltage and GND.
Step 4. Output VoItage becomes to GND.
Step 5. When input voltage(V
SEN
) reaches the state of Vref
≤
V
SEN
×
Rb/(Ra+Rb) at point B, the output of the comparator is reversed, so that the output voltage
becomes to pull-up voltage.