MITSUMI
IC for System Reset PST91XX
IC for System Reset
Monolithic IC PST91XX Series
Outline
April 25, 2002
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
I
CCH
=1.5µA typ. I
CCL
=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)
Packages
TO-92A (PST91
SOT-25A (PST91
)
N)
Applications
1.
2.
3.
4.
5.
Reset circuits for microcomputers, CPUs and MPUs
Reset circuits for logic circuits
Battery voltage check circuits
Back-up power supply switching circuits
Level detection circuits
Pin Assignment
5
1
2
3
1
2
3
V
OUT
V
CC
GND
1
2
4
1
2
NC
SUB
GND
V
OUT
V
CC
3
3
4
5
TO-92A
SOT-25A
(TOP VIEW)
(Note) The pin 2 of SOT-25 package is a SUB terminal. Connect it to GND.
MITSUMI
IC for System Reset PST91XX
Equivalent Circuit Diagram
Absolute Maximum Ratings
Item
Storage temperature
Operating temperature
Power supply voltage
Allowable loss
Note:
(Ta=25
°
C)
Symbol
T
STG
T
OPR
V
CC
Pd
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).
(Ta=25
°
C) (The unit of resistance is
Ω
unless otherwise indicated.)
Measurement
Circuit
Electrical Characteristics
Item
Symbol
Measurement conditions
Min.
Typ. Max. Units
4.6~
Detection Voltage
V
S
1
R
L
=470, V
OL
< 0.4V
=
V
CC
=H
R
L
=470, V
CC
=L
L
H L
-3%
typ.
30
1.9
(0.1V
step)
50
±0.01
0.2
1.0
1.5
20
20
0.65
+3%
typ.
100
V
Hysteresis Voltage
Detection Voltage
Temperature Coefficient
V
S
/
V
S
T
1
1
1
1
1
1
2
2
1
1
1
mV
%/
°
C
R
L
=470, Ta=-20~+75
°
C
V
CC
=V
S
min.-0.05V, R
L
=470
V
CC
=10V, V
O
=V
CC
V
CC
=V
S
min.-0.05V, R
L
=∞
V
CC
=V
S
typ./0.85V, R
L
=∞
C
L
=100pF, R
L
=4.7k
C
L
=100pF, R
L
=4.7k
R
L
=4.7k, V
OL
< 0.4V
=
V
O
=0.4V R
L
=0, 5
V
CC
=V
S
min.-0.05V, V
O
=0.4V
Ta=-30~+80
°
C, V
O
=0.4V
R
L
=0, V
CC
=V
S
min.-0.15V
*
Low Level Output Voltage
Output Leakage Current
Circuit Current at ON Time
Circuit Current at OFF Time
"H" Transmission Delay Time
"L" Transmission Delay Time
Operating Threshold Voltage
Output Current at ON Time 1
V
OL
I
OH
I
CC
L
I
CC
H
tpLH
tpHL
V
OP
L
I
O
L1
I
O
L2
0.4
±0.1
2.0
2.5
60
60
0.85
V
µA
µA
µA
µs
µs
V
mA
Output Current at ON Time 2
Note:
*
3
mA
*
Some models have an expanded temperature range (-30 ~ +85
°
C).
MITSUMI
IC for System Reset PST91XX
Application Circuits
Characteristics
V
S
vs. Ta
4.65
4.60
4.55
(Example: PST9145)
I
O
L vs. Ta
40
35
V
S
(mV)
4.50
4.45
4.40
4.35
-20-10 0 10 20 30 40 50 60 70
I
O
L
30
(mA)
25
20
-20-10 0 10 20 30 40 50 60 70
Ta (
°
C)
Ta (
°
C)
I
CC
H vs. Ta
3
2.5
2
V
S
vs. Ta
100
90
80
70
60
V
S
50
(mV)
40
30
20
10
0
I
CC
H
(µA)
1.5
1
0.5
0
-20-10 0 10 20 30 40 50 60 70
-20-10 0 10 20 30 40 50 60 70
Ta (
°
C)
Ta (
°
C)
V
O
pL vs. Ta
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
V
O
L vs. Ta
240
220
200
180
160
140
120
100
80
60
VopL
(V)
V
O
L
(mV)
-20-10 0 10 20 30 40 50 60 70
-20-10 0 10 20 30 40 50 60 70
Ta (
°
C)
Ta (
°
C)