ETC PST9129

System Reset PST91XX
MITSUMI
System Reset
Monolithic IC PST91XX Series
Outline
The function of this low reset type IC is to accurately reset systems after detecting the supply voltage at the
time of switching power on and instantaneous power off in various CPU and other logic systems. Further, this
IC, with its super low consumption current and high precision voltage detection capacity, is most suited as a
voltage check circuit for a number of products which use batteries.
Features
1. High precision voltage detection
Vs±3% max.
2. Super low current consumption
ICCH=1.5µA typ. ICCL=1.0µA typ.
3. Low operating threshold voltage
0.65V typ.
4. Hysteresis voltage is provided as a detect voltage
50mV typ.
5. Large output current at the time ON
15mA typ.
6. The detect voltage can be selected at your discretion at 0.1V step within the range of 1.9 to 4.6V by the
following stipulation method.
PST91XX
Detected voltage value
(Example : for 4.2V ······ PST9142)
Package
TO-92A (PST91
SOT-25A (PST91
)
N)
Applications
1. Reset circuits for microcomputers, CPU and MPU.
2. Reset circuit for logic circuitry.
3. Battery voltage check circuit.
4. Circuit for changing over to backup battery.
5. Level detecting circuit.
Pin Assignment
5
1
2
3
TO-92A
1
VOUT
2
VCC
3
GND
1
4
2
3
SOT-25A
(TOP VIEW)
(Note) The pin 2 of SOT-25 package is a SUB terminal. Connect it to GND.
1
NC
2
SUB
3
GND
4
VOUT
5
VCC
System Reset PST91XX
MITSUMI
Equivalent Circuit Diagram
Absolute Maximum Ratings
Item
Storage temperature
Operating temperature
Power supply voltage
(Ta=25°C)
Symbol
TSTG
TOPR
VCC
*
Pd
Allowable loss
Note:
Ratings
-40~+125
-20~+75
-0.3~+10
150 (SOT-25A)
300 (TO-92A)
Units
°C
°C
V
mV
*Some models have an expanded temperature range (-30 ~ +85°C).
Electrical Characteristics
Item
(Ta=25°C) (The unit of resistance is Ω unless otherwise indicated.)
Symbol
Measurement
Circuit
Measurement conditions
Min.
Typ. Max. Units
4.6~
VS
Detection Voltage
1
RL=470, VOL <= 0.4V
VCC=H
L
-3%
1.9
+3%
typ.
(0.1V
typ.
V
step)
VS
1
RL=470, VCC=L
VS/ T
1
RL=470, Ta=-20~+75°C
±0.01
Low Level Output Voltage
VOL
1
VCC=VS min.-0.05V, RL=470
0.2
Output Leakage Current
IOH
1
VCC=10V, VO=VCC
Circuit Current at ON Time
ICCL
1
VCC=VS min.-0.05V, RL=∞
Circuit Current at OFF Time
ICCH
1
"H" Transmission Delay Time
tpLH
"L" Transmission Delay Time
Hysteresis Voltage
Detection Voltage
Temperature Coefficient 1
*
H
L
30
50
100
mV
%/°C
0.4
V
±0.1
µA
1.0
2.0
µA
VCC=VS typ./0.85V, RL=∞
1.5
2.5
µA
2
CL=100pF, RL=4.7k
20
60
µs
tpHL
2
CL=100pF, RL=4.7k
20
60
µs
Operating Threshold Voltage
VOPL
1
RL=4.7k, VOL <= 0.4V
0.65
0.85
V
Output Current at ON Time 1
IOL1
1
VO=0.4V RL=0, 5
mA
VCC=VS min.-0.05V, VO=0.4V
Output Current at ON Time 2 1
*
Note:
IOL2
1
Ta=-30~+80°C, VO=0.4V
RL=0, VCC=VS min.-0.15V
*1 Some models have an expanded temperature range (-30 ~ +80°C).
3
mA
System Reset PST91XX
MITSUMI
Application Circuits
Characteristics
(Example: PST9145)
VS vs. Ta
IOL vs. Ta
40
4.65
4.60
35
4.55
VS
(mV)
IOL 30
(mA)
4.50
4.45
25
4.40
4.35
Ta
100
90
80
70
60
VS 50
(mV) 40
30
20
10
0
2.5
2
1.5
1
0.5
-20-10 0 10 20 30 40 50 60 70
Ta
VopL
(V)
-20-10 0 10 20 30 40 50 60 70
Ta (°C)
(°C)
VOpL vs. Ta
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
Ta (°C)
VS vs. Ta
3
0
-20-10 0 10 20 30 40 50 60 70
(°C)
ICCH vs. Ta
ICCH
(µA)
20
-20-10 0 10 20 30 40 50 60 70
VOL vs. Ta
VOL
(mV)
240
220
200
180
160
140
120
100
80
60
-20-10 0 10 20 30 40 50 60 70
-20-10 0 10 20 30 40 50 60 70
Ta (°C)
Ta (°C)