Ricoh R3111x Series User Manual
R3111x SERIES
LOW VOLTAGE DETECTOR
NO.EA-056-080131
OUTLINE
The R3111x series are CMOS-based voltage detector ICs with high detector threshold accuracy and ultra-low
supply current, which can be operated at an extremely low voltage and is used for system reset as an example.
Each of these ICs consists of a voltage reference unit, a comparator, resistors for detector threshold setting,
an output driver and a hysteresis circuit. The detector threshold is fixed with high accuracy internally and does
not require any adjustment.
Three output types, Nch open drain “L” type, Nch open drain “H” type and CMOS type are available.
The R3111x Series are operable at a lower voltage than that for the Rx5VL series, and can be driven by a
single battery.
Six types of packages, TO-92, SOT-89, SOT-23-3, SOT-23-5, SC-82AB, and SON1612-6 are available.
FEATURES
• Supply Current......................................................................Typ. 0.8µA (−VDET=1.5V, VDD=−VDET−0.1V)
• Range of Operating Voltage Range......................................0.7V to 10.0V (T
• Detector Threshold Range....................................................0.9V to 6.0V
• Accuracy Detector Threshold................................................±2.0%
• Temperature-Drift Coefficient of Detector Threshold............Typ. ±100ppm/°C
• Output Types.........................................................................Nch Open Drain “L”, Nch Open Drain “H”, and
CMOS
• Packages ..............................................................................TO-92, SOT-89, SOT-23-3, SOT-23-5,
SC-82AB, SON1612-6
opt=25°C)
APPLICATIONS
• CPU and Logic Circuit Reset
• Battery Checker
• Window Comparator
• Wave Shaping Circuit
• Battery Back-up Circuit
• Power Failure Detector
1
R3111x
BLOCK DIAGRAMS
R3111xxxxA R3111xxxxB
DD
V
OUT
Vref
DD
V
Vref
GND
R3111xxxxC
DD
V
OUT
Vref
GND
OUT
GND
2
R3111x
SELECTION GUIDE
The package type, the detector threshold, the output type and the taping type for the ICs can be selected at
the users’ request. The selection can be made with designating the part number as shown below;
R3111xxxxx-xx-x ← Part Number
↑ ↑ ↑ ↑ ↑ ↑
a b c d e f
Code Contents
Designation of Package Type;
D: SON1612-6
a
E: TO-92
H: SOT-89
N: SOT-23-5, SOT-23-3
Q: SC-82AB
b
Setting Detector Threshold (−V
Stepwise setting with a step of 0.1V in the range of 0.9V to 6.0V is possible.
DET);
Designation of Package Type
c
1: except SOT-23-3
2: SOT-23-3
Designation of Output Type;
d
A: Nch Open Drain (Output "L" at V
B: Nch Open Drain (Output "H" at V
C: CMOS (Output "L" at V
DD=−VDET)
DD=−VDET)
DD=−VDET)
Designation of Packing or Taping Type ;
e
Ex.TO-92: TZ, SOT-89: T1, SOT-23-3, SOT-23-5, SC-82AB, SON1612-6: TR
prescribed as standard directions.
(Refer to Taping Specifications.) Antistatic bag for TO-92: C
Designation of Composition of pin plating
f
-F: Lead free solder plating
(TO-92, SOT-89, SOT-23-3, SOT-23-5, SC-82AB, SON1612-6)
3
R3111x
PIN CONFIGURATIONS
TO-92 SOT-89 SOT-23-3 SOT-23-5 SC-82AB SON1612-6
3
5
4
43
6 5 4
(mark side)
(mark side)
12
3
(mark side)
1 2
(mark side)
123
(mark side)
1
12
3
PIN DESCRIPTIONS
TO-92 SOT-89 SOT-23-3
Pin No. Symbol
1 VDD
2 GND 2 VDD 2 GND
3 OUT 3 GND 3 VDD
SOT-23-5 SC-82AB SON1612-6
Pin No. Symbol
1 OUT 1 OUT 1 OUT
Pin No. Symbol Pin No. Symbol
1 OUT 1 OUT
Pin No. Symbol Pin No. Symbol
(mark side)
2
1 2 3
2 VDD 2 VDD 2 VDD
3 GND 3 NC 3 GND
4 NC 4 GND 4 NC
5 NC 5 VDD
6 NC
4
ABSOLUTE MAXIMUM RATINGS
Symbol Item Rating Unit
VDD Supply Voltage 12 V
R3111x
VOUT1 Output Voltage (CMOS)
VOUT2 Output Voltage (Nch)
V
SS−0.3 to VDD+0.3
V
SS−0.3 to 12
IOUT Output Current 70 mA
Power Dissipation (TO-92)* 300
Power Dissipation (SOT-89)* 900
PD
Power Dissipation (SOT-23-3)* 420
Power Dissipation (SOT-23-5)* 420
Power Dissipation (SC-82AB)* 380
Power Dissipation (SON1612-6)* 500
Topt Operating Temperature Range
Tstg Storage Temperature Range
Tsolder Lead temperature (Soldering)
For Power Dissipation, please refer to PACKAGE INFORMATION to be described.
* )
−40 to 85 °C
−55 to 125 °C
V
V
mW
260°C, 10s
5
R3111x
<
<
<
<
<
<
<
<
ELECTRICAL CHARACTERISTICS
• R3111x09xA/C Topt=25°C
Symbol Item Conditions Min. Typ. Max. Unit
−VDET
VHYS Detector Threshold Hysteresis 0.027 0.045 0.063 V
ISS Supply Current
VDDH Maximum Operating Voltage 10 V
VDDL
IOUT Output Current (Driver Output Pin)
tPLH
∆−VDET/
∆Topt
• R3111x18xA/C Topt=25°C
Detector Threshold 0.882 0.900 0.918 V
Note1
Minimum Operating Voltage
Note2
Output Delay Time
∗
∗
Detector Threshold Temperature
Coefficient
V
DD=0.80V
DD=2.90V
V
Topt=25°C
−40°C
Topt
Nch
V
DS=0.05V,VDD=0.70V
DS=0.50V,VDD=0.85V
V
Pch
V
DS=−2.1V,VDD=4.5V
85°C
0.55 0.70
0.65 0.80
0.01
0.05
1.0
0.8
0.9
0.05
0.50
2.0
100
−40°C
Topt
85°C
±100
2.4
2.7
µA
V
mA
mA
µs
ppm/°C
Symbol Item Conditions Min. Typ. Max. Unit
−VDET
Detector Threshold 1.764 1.800 1.836 V
VHYS Detector Threshold Hysteresis 0.054 0.090 0.126 V
ISS Supply Current
V
DD=1.70V
DD=3.80V
V
0.8
1.0
2.4
3.0
µA
VDDH Maximum Operating Voltage 10 V
VDDL
Minimum Operating Voltage
IOUT Output Current (Driver Output Pin)
Note2
tPLH
∆−VDET/
∆Topt
∗Note1:
Output Delay Time
Detector Threshold Temperature
Coefficient
Minimum operating voltage means the value of input voltage when output voltage maintains 0.1V or less. (In
∗
the case of Nch Open Drain Output type, the output pin is pulled up with a resistance of 470kΩ to 5.0V.)
Note1
∗
Topt=25°C
−40°C
Topt
85°C
Nch
V
DS=0.05V, VDD=0.70V
DS=0.50V, VDD=1.50V
V
Pch
V
DS=−2.1V,VDD=4.5V
100
−40°C
Topt
85°C
0.55 0.70
0.65 0.80
0.01
1.00
1.0
0.05
2.00
2.0
±100
mA
V
mA
µs
ppm/°C
∗Note2: In the case of CMOS Output type: The time interval between the rising edge of VDD input pulse from 0.7V
to (+VDET)+2.0V and output voltage level becoming to ((+VDET)+2.0V)/2.
In the case of Nch Open Drain Output type: The output pin is pulled up with a resistance of 470kΩ to
5.0V, the time interval between the rising edge of VDD input pulse from 0.7V to (+VDET)+2.0V and output
voltage level becoming to 2.5V.
6
R3111x
<
<
<
<
<
<
<
<
• R3111x27xA/C Topt=25°C
Symbol Item Conditions Min. Typ. Max. Unit
−VDET
Detector Threshold 2.646 2.700 2.754 V
VHYS Detector Threshold Hysteresis 0.081 0.135 0.189 V
ISS Supply Current
V
DD=2.60V
DD=4.70V
V
0.9
1.1
2.7
3.3
µA
VDDH Maximum Operating Voltage 10 V
VDDL
Minimum Operating Voltage
IOUT Output Current (Driver Output Pin)
Note2
∗
∆−VDET/
∆Topt
tPLH
Output Delay Time
Detector Threshold Temperature
Coefficient
Note1
∗
Topt=25°C
−40°C
Topt
85°C
Nch
DS=0.05V,VDD=0.70V
V
V
DS=0.50V,VDD=1.50V
Pch
DS=−2.1V,VDD=4.5V
V
100
−40°C
Topt
85°C
0.55 0.70
0.65 0.80
0.01
1.00
1.0
0.05
2.00
2.0
±100
V
mA
mA
µs
ppm/°C
• R3111x36xA/C Topt=25°C
Symbol Item Conditions Min. Typ. Max. Unit
−VDET
Detector Threshold 3.528 3.600 3.672 V
VHYS Detector Threshold Hysteresis 0.108 0.180 0.252 V
ISS Supply Current
V
DD= 3.47V
DD= 5.60V
V
1.0
1.2
3.0
3.6
µA
VDDH Maximum Operating Voltage 10 V
VDDL
Minimum Operating Voltage
IOUT Output Current (Driver Output Pin)
Note2
tPLH
∆−VDET/
∆Topt
∗Note1:
Output Delay Time
Detector Threshold Temperature
Coefficient
Minimum operating voltage means the value of input voltage when output voltage maintains 0.1V or less. (In
∗
the case of Nch Open Drain Output type, the output pin is pulled up with a resistance of 470kΩ to 5.0V.)
Note1
∗
Topt=25°C
−40°C
Topt
85°C
Nch
DS=0.05V,VDD=0.70V
V
V
DS=0.50V,VDD=1.50V
Pch
DS=−2.1V,VDD=4.5V
V
100
−40°C
Topt
85°C
0.55 0.70
0.65 0.80
0.01
1.00
1.0
0.05
2.00
2.0
±100
V
mA
mA
µs
ppm/°C
∗Note2: In the case of CMOS Output type: The time interval between the rising edge of VDD input pulse from 0.7V
to (+VDET)+2.0V and output voltage level becoming to ((+VDET)+2.0V)/2.
In the case of Nch Open Drain Output type: The output pin is pulled up with a resistance of 470kΩ to
5.0V, the time interval between the rising edge of VDD input pulse from 0.7V to (+VDET)+2.0V and output
voltage level becoming to 2.5V.
7
R3111x
<
<
<
<
<
<
<
<
• R3111x45xA/C Topt=25°C
Symbol Item Conditions Min. Typ. Max. Unit
−VDET
Detector Threshold 4.410 4.500 4.590 V
VHYS Detector Threshold Hysteresis 0.135 0.225 0.315 V
ISS Supply Current
V
DD=4.34V
DD=6.50V
V
1.1
1.3
3.3
3.9
µA
VDDH Maximum Operating Voltage 10 V
VDDL
Minimum Operating Voltage
∗
IOUT Output Current (Driver Output Pin)
Note2
tPLH
∆−VDET/
∆Topt
Output Delay Time
Detector Threshold Temperature
Coefficient
∗
Note1
Topt=25°C
−40°C
Topt
85°C
Nch
DS=0.05V, VDD=0.70V
V
V
DS=0.50V, VDD=1.50V
Pch
DS=−2.1V,VDD=8.0V
V
100
−40°C
Topt
85°C
0.55 0.70
0.65 0.80
0.01
1.00
1.5
0.05
2.00
3.0
±100
mA
mA
V
µs
ppm/°C
• R3111x54xA/C Topt=25°C
Symbol Item Conditions Min. Typ. Max. Unit
−VDET
Detector Threshold 5.292 5.400 5.508 V
VHYS Detector Threshold Hysteresis 0.162 0.270 0.378 V
ISS Supply Current
V
DD=5.20V
DD=7.40V
V
1.2
1.4
3.6
4.2
µA
VDDH Maximum Operating Voltage 10 V
VDDL
IOUT
tPLH
∆−VDET/
∆Topt
∗Note1:
Minimum Operating Voltage
Note1
∗
Topt=25°C
−40°C
Topt
85°C
Nch
V
Output Current
(Driver Output Pin)
DS=0.05V, VDD=0.70V
DS=0.50V, VDD=1.50V
V
Pch
V
DS=−2.1V, VDD=8.0V
Note2
Output Delay Time
∗
Detector Threshold Temperature
Coefficient
100
−40°C
Topt
85°C
Minimum operating voltage means the value of input voltage when output voltage maintains 0.1V or less. (In
the case of Nch Open Drain Output type, the output pin is pulled up with a resistance of 470kΩ to 5.0V.)
0.55 0.70
0.65 0.80
0.01
1.00
1.5
0.05
2.00
3.0
±100
mA
mA
V
µs
ppm/°C
∗Note2: In the case of CMOS Output type: The time interval between the rising edge of VDD input pulse from 0.7V
to (+VDET)+2.0V and output voltage level becoming to ((+VDET)+2.0V)/2.
In the case of Nch Open Drain Output type: The output pin is pulled up with a resistance of 470kΩ to
5.0V, the time interval between the rising edge of VDD input pulse from 0.7V to (+VDET)+2.0V and output
voltage level becoming to 2.5V.
8
R3111x
<
<
<
<
<
<
<
<
• R3111Q231B Topt=25°C
Symbol Item Conditions Min. Typ. Max. Unit
−VDET
Detector Threshold 2.254 2.300 2.346 V
VHYS Detector Threshold Hysteresis 0.069 0.115 0.161 V
ISS Supply Current
V
DD=2.2V
DD=4.3V
V
0.9
1.1
2.7
3.3
µA
VDDH Maximum Operating Voltage 10 V
VDDL
Minimum Operating Voltage
∗
IOUT Output Current (Driver Output Pin)
Note2
tPLH
∆−VDET/
∆Topt
Output Delay Time
Detector Threshold Temperature
Coefficient
∗
Note1
Topt=25°C
−40°C
Topt
85°C
Nch
DS=0.50V,VDD=3.0V
V
100
−40°C
Topt
85°C
0.55 0.70
V
0.65 0.80
2.5 mA
µs
±100
ppm/°C
• R3111Q441B Topt=25°C
Symbol Item Conditions Min. Typ. Max. Unit
−VDET
VHYS Detector Threshold Hysteresis 0.132 0.220 0.308 V
ISS Supply Current
VDDH Maximum Operating Voltage 10 V
VDDL
IOUT
tPLH
∆−VDET/
∆Topt
∗Note1:
∗Note2: In the case of CMOS Output type: The time interval between the rising edge of VDD input pulse from 0.7V
Detector Threshold 4.312 4.400 4.488 V
Note1
Minimum Operating Voltage
∗
Output Current
(Driver Output Pin)
Note2
Output Delay Time
∗
Detector Threshold Temperature
Coefficient
V
DD=4.24V
DD=6.4V
V
Topt=25°C
−40°C
Nch
V
DS=0.50V, VDD=5.5V
Topt
85°C
0.55 0.70
0.65 0.80
2.5 mA
100
−40°C
Topt
85°C
1.1
1.3
±100
3.3
3.9
µA
V
µs
ppm/°C
Minimum operating voltage means the value of input voltage when output voltage maintains 0.1V or less. (In
the case of Nch Open Drain Output type, the output pin is pulled up with a resistance of 470kΩ to 5.0V.)
to (+VDET)+2.0V and output voltage level becoming to ((+VDET)+2.0V)/2.
In the case of Nch Open Drain Output type: The output pin is pulled up with a resistance of 470kΩ to
5.0V, the time interval between the rising edge of VDD input pulse from 0.7V to (+VDET)+2.0V and output
voltage level becoming to 2.5V.
9
R3111x
+
+
+
+
TIMING CHART
Supply
Voltage
(VDD)
Minimum Operating Voltage
Released Voltage
Detector Threshold
+V
-
V
V
GND
DET
DET
DDL
Detector Threshold
Hysteresis Hysteresis Hysteresis
Detector Threshold Detector Threshold
Output
Voltage
OUT
(V
)
Pull-up Voltage
GND
t
PLH
t
PLH
t
PLH
R3111xxxxA R3111xxxxB R3111xxxxC
DEFINITION OF OUTPUT DELAY TIME
Output Delay Time (tPLH) is defined as follows:
1. In the case of Nch Open Drain Output:(R3111xxxxA/B)
Under the condition of the output pin (OUT) is pulled up through a resistor of 470kΩ to 5V, the time interval
between the rising edge of V
2. In the case of CMOS Output:(R3111xxxxC)
The time interval between the rising edge of V
voltage to ((+V
DET)+2.0V)/2.
+V
DET
+2.0V
Supply
Voltage
(V
DD
0.7V
)
GND
5.0V
DD pulse from 0.7V to (+VDET)+2.0V and becoming of the output voltage to 2.5V.
DD pulse from 0.7V to (+VDET)+2.0V and becoming of the output
Supply
Voltage
(V
+V
DD
)
DET
2.0V
0.7V
GND
5.0V
Supply
Voltage
DD
(V
V
)
V
DET
+2.0V
DET
+2.0V
0.7V
GND
Output
Voltage
OUT
(V
)
2.5V
GND
PHL
t
PLH
t
Output
Voltage
OUT
(V
2.5V
)
GND
t
PHL
t
PLH
Output
Voltage
(V
OUT
DET
V
)
+2.0V
2
GND
t
PHL
t
PLH
Nch Open Drain Output Nch Open Drain Output CMOS Output
(R3111xxxxA) (R3111xxxxB) (R3111xxxxC)
10
R3111x
11
R3111x
ELECTRICAL CHARACTERISTICS BY DETECTOR THRESHOLD
• R3111x09x to R3111x60x
Part
Number
R3111x09xx 0.882 0.900 0.918 0.027 0.045 0.063 0.9 2.7
R3111x10xx 0.980 1.000 1.020 0.030 0.050 0.070
R3111x11xx 1.078 1.100 1.122 0.033 0.055 0.077
R3111x12xx 1.176 1.200 1.224 0.036 0.060 0.084
R3111x13xx 1.274 1.300 1.326 0.039 0.065 0.091
R3111x14xx 1.372 1.400 1.428 0.042 0.070 0.098
R3111x15xx 1.470 1.500 1.530 0.045 0.075 0.105
R3111x16xx 1.568 1.600 1.632 0.048 0.080 0.112
R3111x17xx 1.666 1.700 1.734 0.051 0.085 0.119
R3111x18xx 1.764 1.800 1.836 0.054 0.090 0.126
R3111x19xx 1.862 1.900 1.938 0.057 0.095 0.133
R3111x20xx 1.960 2.000 2.040 0.060 0.100 0.140
R3111x21xx 2.058 2.100 2.142 0.063 0.105 0.147
R3111x22xx 2.156 2.200 2.244 0.066 0.110 0.154
R3111x23xx 2.254 2.300 2.346 0.069 0.115 0.161
R3111x24xx 2.352 2.400 2.448 0.072 0.120 0.168
R3111x25xx 2.450 2.500 2.550 0.075 0.125 0.175
R3111x26xx 2.548 2.600 2.652 0.078 0.130 0.182
R3111x27xx 2.646 2.700 2.754 0.081 0.135 0.189
R3111x28xx 2.744 2.800 2.856 0.084 0.140 0.196
R3111x29xx 2.842 2.900 2.958 0.087 0.145 0.203
R3111x30xx 2.940 3.000 3.060 0.090 0.150 0.210
R3111x31xx 3.038 3.100 3.162 0.093 0.155 0.217
R3111x32xx 3.136 3.200 3.264 0.096 0.160 0.224
R3111x33xx 3.234 3.300 3.366 0.099 0.165 0.231
R3111x34xx 3.332 3.400 3.468 0.102 0.170 0.238
R3111x35xx 3.430 3.500 3.570 0.105 0.175 0.245
R3111x36xx 3.528 3.600 3.672 0.108 0.180 0.252
R3111x37xx 3.626 3.700 3.774 0.111 0.185 0.259
R3111x38xx 3.724 3.800 3.876 0.114 0.190 0.266
R3111x39xx 3.822 3.900 3.978 0.117 0.195 0.273
R3111x40xx 3.920 4.000 4.080 0.120 0.200 0.280
R3111x41xx 4.018 4.100 4.182 0.123 0.205 0.287
R3111x42xx 4.116 4.200 4.284 0.126 0.210 0.294
R3111x43xx 4.214 4.300 4.386 0.129 0.215 0.301
R3111x44xx 4.312 4.400 4.488 0.132 0.220 0.308
R3111x45xx 4.410 4.500 4.590 0.135 0.225 0.315
R3111x46xx 4.508 4.600 4.692 0.138 0.230 0.322
R3111x47xx 4.606 4.700 4.794 0.141 0.235 0.329
R3111x48xx 4.704 4.800 4.896 0.144 0.240 0.336
R3111x49xx 4.802 4.900 4.998 0.147 0.245 0.343
R3111x50xx 4.900 5.000 5.100 0.150 0.250 0.350
R3111x51xx 4.998 5.100 5.202 0.153 0.255 0.357
R3111x52xx 5.096 5.200 5.304 0.156 0.260 0.364
R3111x53xx 5.194 5.300 5.406 0.159 0.265 0.371
R3111x54xx 5.292 5.400 5.508 0.162 0.270 0.378
R3111x55xx 5.390 5.500 5.610 0.165 0.275 0.385
R3111x56xx 5.488 5.600 5.712 0.168 0.280 0.392
R3111x57xx 5.586 5.700 5.814 0.171 0.285 0.399
R3111x58xx 5.684 5.800 5.916 0.174 0.290 0.406
R3111x59xx 5.782 5.900 6.018 0.177 0.295 0.413
R3111x60xx 5.880 6.000 6.120 0.180 0.300 0.420
*1)
In the case of CMOS output ty pe; when the voltage is forced to VDD from 0.7V to (+V
((+V
DET
(+V
DET
*2) VDD value when Output Voltage is equal or less than 0.1V. In the case of Nch open drain output type, the output pin is pulled up to 5V through 470kΩ
)+2.0V, time interval between the rising edge of VDD and the reaching point at ((+V
resistor.
Condition 1: Topt=25°C
Condition 2: −40°C
Detector Threshold
[V]
<
=
85°C
−VDET
Min. Typ. Max. Min. Typ. Max. Condition Typ. Max. Condition Typ. Max.
)+2.0V)/2. In the case of Nch open drain output type : The output pin is pulled up to 5V through 470kΩ, and when the voltage is forced to VDD from 0.7V to
<
Topt
=
Detector Threshold
Hysteresis
[V]
HYS
V
Supply Current 1 Supply Current 2
V
DD=
(
−VDET)
[µA]
I
I
SS1
0.8 2.4
[µA]
SS2
1.0 3.0
−0.10V
0.9 2.7 1.1 3.3
V
DD=
(
−VDET)
−0.13V
DD=
V
(
−VDET)
1.0 3.0 1.2 3.6
1.1 3.3 1.3 3.9
DD=
V
(
−VDET)
+2.0V
−0.16V
V
DD=
(
−VDET)
1.2 3.6
1.4 4.2
−0.20V
DET
)+2.0V, time interval between the rising ed ge of VDD and the reaching point at
DET
)+2.0V)/2.
12
R3111x
<
Output Current 1 *3 Output Current 2 *3
[mA]
IOUT1
Condition Min. Typ. Condition Min. Typ. Max. Typ. Max. Condition Typ.
I
OUT2
VDD=
0.85V
[mA]
0.05 0.5
Output Delay
Time
[µs]
t
PLH
Minimum
Operating Voltage
[V]
DDL
V
Detector Threshold
Temperature Coefficient
∆−V
DET/∆Topt
[
ppm/°C
]
Nch
V
DS=0.05V
V
DD=0.7V
0.01 0.05
Nch
V
DS=
0.5V
VDD=
1.0V
DD=
V
1.5V
0.2 1.0
1.0 2.0
100
*2
Condition 1
1
*
0.55
Condition 2
0.65
2
*
Condition 1
0.70
Condition 2
0.80
−40°C
Topt
<
=
±100
85°C
*3) Output Current (IOUT) of R3111xxxxB has not been described. Please inquire details.
13
R3111x
p
A
OPERATION
• Operation of R3111xxxxA
Com
Ra
Rb
Vref
Rc
Released Voltage
Detector Threshold
Supply Voltage
DD
(V
)
Minimum Operating Voltage
Pull-up Voltage
Output Voltage
OUT
(V
)
+V
-
GND
GND
• Explanation of operation
arator
13 5
DET
DET
V
DDL
V
Tr.1
2 4
Detector Threshold
Hysteresis
DD
V
OUT
Nch
GND
Block Diagram (R3111xxxxA)
Step 1 2 3 4 5
B
Comparator (+)
Pin Input Voltage
Comparator Output H L Indefinite L H
Output Tr. Nch OFF ON Indefinite ON OFF
Output
Delay Time
PLH
t
Operation Diagram
OUT pin should be pulled-up to
DD
V
or an external voltage level.
I II II II I
Tr.1 OFF ON Indefinite ON OFF
Rb+Rc
I
Ra+Rb+Rc
II
Rb
Ra+Rb
×V
×V
DD
DD
Step 1. The output voltage is equal to the pull-up voltage.
Step 2. At Point “A”, Vref
>
VDD×(Rb+Rc)/(Ra+Rb+Rc) is true, as a result, the output of comparator is reversed
=
from "H" to "L", therefore the output voltage becomes the GND level. The voltage level of Point A means
a detector threshold voltage (−V
DET).
Step 3. When the supply voltage is lower than the minimum operating voltage, the operation of the output
transistor becomes indefinite. The output voltage is equal to the pull-up voltage.
Step 4. The output Voltage is equal to the GND level.
Step 5. At Point “B”, Vref
<
VDD×Rb/(Ra+Rb) is true, as a result, the output of comparator is reversed from "L" to
=
"H", then the output voltage is equal to the pull-up voltage. The voltage level of Point B means a released
voltage (+V
DET).
∗) The difference between a released volt age and a d etector threshold volt age i s a detector threshold hysteresi s.
14
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