LOW VOLTAGE DETECTOR WITH OUTPUT DELAY
R3112xxx1A/C Series
2001. Ap r. 4
Rev. 1.10 - 1 -
OUTLINE
The R3112 Series are voltage detector ICs with high detector threshold accuracy and ultra-low
supply current by CMOS process, which can be operated at an extrem ely low voltage and is used for
system reset as an example.
Each of these ICs consists of a voltage reference unit, a comparator, resistor net for detector
threshold setting, an output driver, a hysteresis circuit, and an output delay circuit. The detector
threshold is f ixed with high acc urac y intern all y and does no t requ ire an y adjustm ent. Two output types ,
Nch open drain type and CMOS type are available.
Two types of packages, SOT-23-5 and ultra small SC-82AB can be selected so that high density
mounting on boards is possible.
FEATURES
Built-in Output Delay Circuit TYP. 100ms with an external capacitor: 0.022µF
Ultra-low Supply Current TYP. 1.0µA (VDD=3.5V)
Wide Range of Operating Voltage 0.76.0V(Topt=25°C)
Detector Threshold Stepwise setting with a s tep of 0.1V i n th e r ang e of 0.9 V t o 5. 0V
is possible.
High Accuracy Detector Threshold ±2.0%
Low Temperature-Drift Coefficient of Detector Threshold TY P. ±100ppm/°C
Two Output Types Nch Open Drain and CMOS
Two Types of Packages SOT-23-5 (Mini-mold), SC-82AB
APPLICATIONS
CPU and Logic Circu it Res et
Battery Checker
Window Comparator
Wave Shaping Circuit
Battery Back-up Circuit
Power Failure Detector
BLOCK DIAGRAMS
R3112XXX1A R3112XXX1C
VDD
Vref
OUT
GND
CD
+
-
RD
Vref
VDD
OUT
GND
CD
+
--
RD
Rev. 1.10 - 2 -
OPERATION
OUT
Vref
VDD
GND
CD
+
-Pch
Nch
Schmitt Trigger
Comparator
Ra
Rb
Rc
Tr.1 Tr.2
RD
Output Capacitor
Current Source
Fig. 1 Block Diagram with an external capacitor
Output Voltage
(OUT)
Supply Voltage
(VDD)
HYSTERESIS RANGE
A
B
Released Voltage
+
VDET
Detector Threshold-VDET
Minimum Operating
Voltage
VDDL
GND
GND
Delay Time
1234 5 Operation Status 12 3 45
Comparator(-) Pin
Input Voltage ΙΙΙ ΙΙ ΙΙΙ
Comparator Output LH
Indefinite HL
Tr.1, 2 OFF ON Indefinite ON OFF
Nch OFF ON Indefinite ON OFF
Output Tr. Pch ON OFF Indefinite OFF ON
Ι Rb+Rc ×VDD
Ra+Rb+Rc
ΙΙ ×VDD
Fig. 2 Operation Diagram
1. Output Voltage is equal to Supply Voltage. (As for Nch Open Drain Type, equal to pull-up voltage.)
2. When the Supply Voltage is down to the detector threshold voltage level(Point A),
VrefVDD×(Rb+Rc)/(Ra+Rb +Rc) is tru e, then outp ut of the com par ator is rever sed fr om “L” to “H”, ther efore
Output Voltage becomes GND level.
3. W hen the Suppl y Voltage is lo wer than Minim um O perating Vo ltage, the o peration of Outpu t Transistor is
indefinite. In the case of Nch Open Drain Type, Output Voltage is equal to pull-up Voltage.
4. Output Voltage becomes GND level.
5. When the Supply Voltage is higher than released voltage (Point B), VrefVDD×Rb/(Ra+Rb) is true, then
Output of the comparator reaches the threshold level, and Output of Shmitt Trigger is reversed from “H” to
“L”, then Output Voltage is equal to Supply Voltage. (As for Nch Open Drain Type, equal to pull-up voltage.)
*) The difference between Released Voltage and Detector Threshold Voltage means Hysteresis Range
Voltage.
Rb
Ra+Rb
Rev. 1.10 - 3 -
Operation of Output Delay
Supply Voltage
Capac it o r V olt ag e
Output Voltage
W hen the Supply Voltage which is higher than Released Voltage is forced to VDD pin, charge to an
external capacitor starts, then capacitor voltage increases. Until the capacitor voltage reaches to CD
Pin Threshold Voltage, Output Voltage maintains “L”. When the capacitor voltage becomes higher than
CD pin threshold voltage, Output Voltage is reversed from “L” to “H”. Where, the time interval between
th e ri s ing edge of Supply Voltage and Out p ut Volt ag e Rev ers e point mean s Out put De lay Tim e.
Output Delay Time
Output Delay Time (tD) can be calculated with the next formula.
tD=0.69RDCD(s)
RD is i nternal resistor a nd set at 6. 5M(TYP.) typically. CD(F) describes the capacitance value of an
external capacitor. Therefore,
tD=0.696.5106 CD(s)
CD Pin Threshold Voltage (VTCD)
Released V olt ag e (+VDET)
GND
GND
Output Delay Ti me (tD)
Rev. 1.10 - 4 -
SELECTION GUIDE
T he package t ype, the de tector thr eshold, the o utput t ype, and the t aping t ype of R3112 Series can
be designated at the users’ request by specifying the part number as follows;
R3112
×××1×-××←Part Number
a b c
d
Code Contents
a Designation of Package Type;
Q:SC-82AB N:SOT-23-5
b Setting Detector Threshold (-VDET);
Stepwise setting with a step of 0.1V in the range of 0.9V to 5.0V is possible.
cDesignation of Output Type;
A: Nch Open Drain
C: CMOS
dDesignation of Packing or Taping Ty pe ;
Ex. SOT-23-5, SC-82AB: TR is prescribed as standard directions.
(Refer to Taping Specifications)
PIN CONFIGURATION
SOT-23-5 SC-82AB
MARK SIDE
1 2 3
5 4
1 2
4 3
MARK SIDE
PIN DESCRIPTION
SOT-23-5            SC-82AB
Pin No. Symbol Description Pin No. Symbol Description
1 OUT Output Pin(Output “L” at detector
threshold, Output “H” at released
voltage)
1V
DD Volta ge Sup ply Pin
2V
DD Volta ge Sup ply Pin 2 GND Ground Pi n
3 GND Gr ound Pi n 3 CDPin for External Capacitor
(for setting output delay)
4 NC No Connection 4 OUT Output Pin(Output “L”
at detector threshold, Output
“H” at released voltage)
5C
DPin for External Capacitor (for
setting output delay)
Rev. 1.10 - 5 -
ABSOLUTE MAXIMUM RATINGS
Symbol Item Rating Unit
VDD Supply Voltage 6.5 V
VOUT1 Output Voltage(CMOS) VSS-0.3VDD+0.3 V
VOUT2 Output Voltage(Nch) VSS-0.36.5 V
IOUT Output Current 20 mA
Power Dissipation(SOT23-5) 250PD Power Dissipation(SC82-AB) 150 mW
Topt Operating Temperature Range -4085 °C
Tstg Storage Temperature Range -55125 °C
Tsolder Lead temperature (Soldering) 260°C, 10s
ABSOLUTE MAXIMUM RATINGS
Absolute Max imum ratings are thresho ld lim it v alues that m ust not be exc eeded e ver for an inst ant
under any conditions. Moreover, such values for any two items must not be reached simultaneously.
Operation above these absolute maximum ratings may cause degradation or permanent damage to
the device. These are stress ratings only and do not necessarily imply functional operation below
these lim its .
R3112x091A/C
T
opt=25°C
Symbol Item Conditions MIN. TYP. MAX. Unit
-VDET Detector Threshold 0.882 0.900 0.918 V
VHYS Detector Threshold
Hysteresis 0.027 0.045 0.063 V
VDD=0.80V 0.6 2.0ISS Supply Current 1.90V 0.5 2.0 µA
VDDH Maximum Operating
Voltage 6.0 V
Topt=25°C0.70VDDL Minimum Operating
Voltage*Note1 -40°C Topt 85°C0.80
V
10 120 µA
Nch
VDS=0.05V,VDD=0.70V
VDS=0.50V,VDD=0.85V 0.05 0.9 mA
IOUT Output Current
(Driver Output Pin) Pch
VDS=-2.1V,VDD=4.5V 1.0 3.5 mA
VTCD CD pin Threshold Voltage VDD=0.99V 0.297 0.495 0.693 V
VDS=0.10 V, VDD=0.70V 2 70ICD CD pin Output Current VDS=0. 50 V, VDD=0.85V 10 400 µA
RDOutput Dela y Resistanc e 3.25 6.50 13.00 M
-VDET/T Detector Threshold
Temperature Coefficient -40°C Topt 85°C±100 ppm/°C
Rev. 1.10 - 6 -
R3112x271A/C T
opt=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 0.189 V
VDD=2.60V 1.0 2.5ISS Supply Current 3.70V 0.5 3.0 µA
VDDH Maximum Operating Voltage 6.0 V
Topt=25°C0.7VDDL Minimum Operating Voltage*Note1
-40°C Topt85°C0.8
V
Nch
VDS=0.05V,VDD=0.70V 10 120 µA
VDS=0.50V,VDD=1.50V 1.0 3.0 mA
IOUT Output Current
(Driver Output Pin) Pch
VDS=-2.1V,VDD=4.5V 1.0 3.5 mA
VTCD CD pin Threshold Voltage VDD=2.97V 0.891 1.485 2.079 V
VDS=0.1V, VDD=0.7V 2.0 70 µAICD CD pin Output Current VDS=0.5V, VDD=1.5V 200 500
RDOutput Dela y Resistanc e 3.25 6.50 13.00 M
-VDET/T Detector Threshold
Temperature Coefficient -40°C Topt85°C±100 ppm/°C
R3112x501A/C T
opt=25°C
Symbol Item Conditions MIN. TYP. MAX. Unit
-VDET Detector Threshold 4.900 5.000 5.100 V
VHYS Detector Threshold Hysteresis 0.150 0.250 0.350 V
VDD=4.9V 1.5 2.5ISS Supply Current 6.0V 0.6 3.0 µA
VDDH Maximum Operating Voltage 6.0 V
Topt=25°C0.7VDDL Minimum Operating Voltage*Note1
-40°C Topt85°C0.8
V
Nch
VDS=0.05V,VDD=0.70V 10 120 µA
VDS=0.50V,VDD=1.50V 1.0 3.0 mA
IOUT Output Current
(Driver Output Pin) Pch
VDS=-2.1V,VDD=6.0V 1.5 4.5 mA
VTCD CD pin Threshold Voltage VDD=2.97V 1.650 2.750 3.850 V
VDS=0.1V, VDD=0.7V 2.0 70 µAICD CD pin Output Current VDS=0.5V, VDD=1.5V 200 500
RDOutput Dela y Resistanc e 3.25 6.50 13.00 M
-VDET/T Detector Threshold
Temperature Coefficient -40°CTopt85°C±100 ppm/°C
*Note1: Minimum Operating Voltage means the value of input voltage when output voltage maintains
0.1V or less.
(In the case of Nch Open Drain T y pe, Output pin is pulled up with a resistance of 470k to 5.0V.)
Rev. 1.10 - 7 -
TEST CIRCUITS
*Pull-up circuit is not necessary for CMOS Output type, o r R3112XXXXC.
Supply Current Test Circuit Detector Threshold Test Circuit
R3112X
Series
VDD
GND
ISS
R3112
Series
VDD
GND
VIN
470k
OUT
+5V or
VDD
Nch Driver Output Current Test Circuit Pch Driver Output Current Test Circuit *Apply only to
CMOS
R3112
Series
VDD
GND
VIN
OUT VDS
IOUT R3112X
Series
VDD
GND
VIN
OUT VDD+VDS
IOUT
CD Pin Threshold Test Circuit CD Pin Output Current Test Circuit
R3112X
Series
VDD
GND
VIN
470k
OUT
+5V or VDD
VDS
CD R3112X
Series
VDD
GND
VIN
VDS
CD
ICD
Output Delay Time Test Circuit
R3112X
Series
VDD
GND
VIN
470k
OUT
+5V
CD
CD
GND
GND
50%
100%
0.7V
+VDET+2 . 0V or 6.0V
Input
Voltage
Out
p
ut V olta
g
e
Rev. 1.10 - 8 -
TYPICAL CHARACTERISTICS
1) Supply Current vs. Input Voltage
R3112X091X R3112X131X
0
0.3
0.6
0.9
1.2
1.5
01234567
Input Vol tage VIN(V)
Supply Current Iss (uA)
0
0.3
0.6
0.9
1.2
1.5
01234567
Input Voltage VIN(V)
Supply Current Iss (uA)
R3112X271X R3112X451X
0
0.3
0.6
0.9
1.2
1.5
01234567
Input Voltage VIN(V)
Supply Current Iss(uA)
0
0.4
0.8
1.2
1.6
2
01234567
Input Voltage VIN (V)
Supply Current Iss (uA)
2) Detector Threshold vs. Temperature
R3112X091X R3112X131X
0.86
0.88
0.90
0.92
0.94
0.96
0.98
-50 -25 0 25 50 75 100
Tem perature Topt
Detector Threshold/Released Voltage
VDETV
1.26
1.28
1.30
1.32
1.34
1.36
1.38
1.40
1.42
-50 -25 0 25 50 75 100
Temperature Topt
Detector Threshold/Released Voltage
VDETV
Topt=85°C
25°C
-40°C-40°C
Topt=85°C
25°C
-40°C
25°CTopt=85°C
Topt=85°C
25°C
-40°C
(°C)
+VDET
-VDET
(°C)
+VDET
-VDET
Rev. 1.10 - 9 -
R3112X271X R3112X451X
2.60
2.65
2.70
2.75
2.80
2.85
2.90
-50 -25 0 25 50 75 100
Temperature Topt
Detector Threshold/Released Voltage
VDETV
4.35
4.40
4.45
4.50
4.55
4.60
4.65
4.70
4.75
-50 -25 0 25 50 75 100
Temperature Topt
Detector Threshold/Released Voltage
VDETV
3) Output Voltage vs. Input Voltage
R3112X091X R3112X091A
Nch Output Type: VDD pull up 5V pull up via 470k
0.0
0.2
0.4
0.6
0.8
1.0
0 0.2 0.4 0.6 0.8 1
Input V oltag e VIN (V)
Output Voltage V OUT(V)
0.0
1.0
2.0
3.0
4.0
5.0
6.0
0 0.2 0.4 0.6 0.8 1
Input V oltag e VIN(V)
Output Voltage V OUT(V)
R3112X131X R3112X131A
Nch Output Type: VDD pull up 5V pull up via 470k
0
0.3
0.6
0.9
1.2
1.5
0 0.3 0.6 0.9 1.2 1.5
Input Voltage VIN(V)
Output Voltage V OUT(V)
0.0
1.0
2.0
3.0
4.0
5.0
6.0
0 0.3 0.6 0.9 1.2 1.5
Input Voltage VIN(V)
Output Voltage VOUT(V)
(°C)
+VDET
-VDET
+VDET
-VDET
(°C)
Topt=-40°C
25°C
85°C
Topt=-40°C
25°C
85°C
Topt=-40°C
25°C
85°C
Topt=-40°C
25°C
85°C
Rev. 1.10 - 10 -
R3112X271X R3112X271A
Nch Output Type: VDD pull up 5V pull up via 470k
0.0
0.5
1.0
1.5
2.0
2.5
3.0
0.0 0.5 1.0 1.5 2.0 2.5 3.0
Input Vol tage VIN(V)
Output Voltage VOUT(V)
0.0
1.0
2.0
3.0
4.0
5.0
6.0
0.0 0.5 1.0 1.5 2.0 2.5 3.0
Input Vol tage VIN(V)
Output Voltage VOUT(V)
R3112X451X R3112X451A
Nch Output Type: VDD pull up 5V pull up via 470k
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
Input Voltage VIN(V)
Output Voltage VOUT(V)
0.0
1.0
2.0
3.0
4.0
5.0
6.0
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
Input Voltage VIN(V)
Output Voltage VOUT(V)
4) Nch Driver Output Current vs. VDS
R3112X091X R3112X131X
0
0.2
0.4
0.6
0.8
1
1.2
0 0.2 0.4 0.6 0.8 1
VDS(V)
Output Current IOUT(mA)
0
0.5
1
1.5
2
2.5
0 0.2 0.4 0.6 0.8 1
VDS(V)
Output Current IOUT(mA)
Topt=-40°C
25°C85°C
Topt=-40°C
25°C
85°C
Topt=-40°C
25°C85°C
Topt=-40°C
25°C
85°C
VDD=0.85V
VDD=0.7V
VDD=0.7V
VDD=0.85V
VDD=1.0V
Rev. 1.10 - 11 -
R3112X271X R3112X451X
0
4
8
12
16
20
00.511.522.5
VDS (V)
Output Current IOUT(mA)
0
4
8
12
16
20
00.511.522.533.54
VDS(V)
Output Current IOUT(mA)
5) Nch Driver Output Current vs. Input Voltage
R3112X091X R3112X131X
0.0
0.5
1.0
1.5
2.0
0 0.2 0.4 0.6 0.8 1
Input Vol tage VIN(V)
Output Current IOUT(mA)
0
1
2
3
4
5
0 0.3 0.6 0.9 1.2 1.5
Input Vol tage VIN(V)
Output Current IOUT(mA)
R3112X271X R3112X451X
0
1
2
3
4
5
00.511.522.53
Input Vol tage VIN(V)
Output Current IOUT(mA)
0
1
2
3
4
5
012345
Input Vol tage VIN(V)
Output Current IOUT(mA)
VDD=1.0V
VDD=1.5V
VDD=2.0V
VDD=2.5V
VDD=1.0V
VDD=1.5V
VDD=2.0V
VDD=2.5V
VDD=3.0V
VDD=3.5V
VDD=4.0V
Topt=85°C
25°C
-40°C Topt=85°C
25°C
-40°C
Topt=85°C
25°C
-40°C
Topt=85°C
25°C
-40°C
Rev. 1.10 - 12 -
6) Pch Driver Output Current vs. Input Voltage
R3112X091C R3112X131C
0
1
2
3
4
5
6
01234567
Input Vol tage VIN(V)
Output Current IOUT(mA)
0
1
2
3
4
5
6
01234567
Input Vol tage VIN(V)
Output Current IOUT(mA)
R3112X271C R3112X451C
0
1
2
3
4
5
6
01234567
Input Vol tage VIN(V)
Output Current IOUT(mA)
0
1
2
3
4
5
6
01234567
Input Vol tage VIN(V)
Output Current IOUT(mA)
7) CD Pin Threshold Voltage vs. Temperature
R3112X091X VDD=0.99V R3112X131X VDD=1.43V
0.2
0.3
0.4
0.5
0.6
0.7
0.8
-50 -25 0 25 50 75 100
Temperature Topt
CD Pin Threshold Voltage Vtcd V)
0.4
0.5
0.6
0.7
0.8
0.9
1.0
-50 -25 0 25 50 75 100
Temperature Topt
CD Pin Threshold Voltage VtcdV
VDS=-2.1V
-1.5V
-1.0V
-0.5V
VDS=-2.1V
-1.5V
-1.0V
-0.5V
-0.5V
-1.0V
-1.5V
VDS=-2.1V VDS=-2.1V -1.5V
-1.0V
-0.5V
(
°C
)
(
°C
)
Rev. 1.10 - 13 -
R3112X271X VDD=2.97V R3112X451X VDD=4.95V
1.3
1.4
1.5
1.6
1.7
1.8
1.9
-50 -25 0 25 50 75 100
Temperature Topt
CD Pin Threshold Voltage VtcdV
2.3
2.4
2.5
2.6
2.7
2.8
2.9
-50 -25 0 25 50 75 100
Temperature Topt
CD Pin Threshold Voltage Vtcd
V
8) CD Pin Output Current vs. Input Voltage
R3112X091X VDS=0.5V R3112X131X VDS=0.5V
0
0.2
0.4
0.6
0.8
1
0 0.2 0.4 0.6 0.8 1
Input Vol tage VIN(V)
CD Pin Output Current Icd (mA)
0
0.2
0.4
0.6
0.8
1
0 0.3 0.6 0.9 1.2 1.5
Input Vol tage VIN(V)
CD Pin Output Current Icd (mA)
R3112X271X VDS=0.5V R3112X451X VDS=0.5V
0
0.2
0.4
0.6
0.8
1
00.511.522.53
Input Vol tage VIN(V)
CD Pin Output Current Icd (mA)
0
0.2
0.4
0.6
0.8
1
012345
Input Vol tage VIN(V)
CD Pin Output Current Icd (mA)
(
°C
)
(
°C
)
Topt=-40°C
25°C
85°C
Topt=-40°C25°C
85°C
To
p
t=-40°C
25°C
85°C
Topt=-40°C
25°C
85°C
Rev. 1.10 - 14 -
9) CD Pin Output Current vs. VDS (Topt=25°C)
R3112X091X R3112X131X
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0 0.2 0.4 0.6 0.8 1
VDS(V)
CD Pin Output Current Icd (mA)
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
0 0.2 0.4 0.6 0.8 1
VDS(V)
CD Pin Output Current Icd(m
A
R3112X271X R3112X451X
0
0.5
1
1.5
2
2.5
3
00.511.522.5
VDS(V)
CD Pin Output Current Icd (mA)
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
0 0.5 1 1.5 2 2.5 3 3.5 4
VDS(V)
CD Pin Output Current Icd (mA)
10) Output Delay Time vs. External Capacitance (Topt=25°C)
R3112X091X R3112X131X
0.01
0.1
1
10
100
1000
0.0001 0.001 0.01 0.1
External Capacitanc e Cd (uF
Output Delay Time txms
0.01
0.1
1
10
100
1000
0.0001 0.001 0.01 0.1
External Capacit ance Cd(uF
Output Delay Time tDms
VDD=0.85V
VDD=0.7V
VDD=0.7V
VDD=0.85V
VDD=1.0V
VDD=1.0V
VDD=1.5V
VDD=2.0V
VDD=2.5V
VDD=1.0V
VDD=1.5V
VDD=2.0V
VDD=2.5V
VDD=3.0V
VDD=3.5V
VDD=4.0V
tD
t
p
HL
tD
t
p
HL
Rev. 1.10 - 15 -
R3112X271X R3112X451X
0.01
0.1
1
10
100
1000
0.0001 0.001 0.01 0.1
External Capacit ance Cd(uF
Output Delay Time txms
0.01
0.1
1
10
100
1000
0.0001 0.001 0.01 0.1
External Capacitance Cd(uF
Output Delay Time tx
ms
11) Delay Circuit Resistance vs. Temperature
R3112XXX1X
3
4
5
6
7
8
9
10
11
12
13
-50 -25 0 25 50 75 100
Temperature Topt
Delay Circuit Resistance Rd
MOhm
tD
t
p
HL
tD
t
p
HL