MITSUMI PST597

System Reset PST596~598
MITSUMI
System Reset
Monolithic IC PST596~598 Series
Outline
These ICs function in a variety of CPU systems and other logic systems, to detect power supply voltage and
reset the system accurately when power is turned on or interrupted, and has a built-in fixed delay time
generating circuit. This series has been represented in the past by PST591~595, and these new system reset
ICs offer ultra-small size and low current consumption.
Features
1. Fixed delay time setting by counter timer
2. Low operating limit voltage
3. Hysteresis voltage provided in detection voltage
4. Low current consumption
5. 3 delay time products available
6. Each product has 10 detection voltage ranks.
Package
SOT-25A (PST59
N) (with manual reset pin)
contains detection voltage rank.
*
Applications
1. Reset circuits in microcomputers, CPUs and MPUs
2. Logic circuit reset circuits.
3. Battery voltage check circuits.
4. Back-up power supply switching circuits.
5. Level detection circuits.
6. Mechanical reset circuits
0.65V typ.
50mV typ.
ICCH=15µA typ.
PST596 50mS
PST597 100mS
PST598 200mS
C : 4.5V typ.
H : 3.1V typ.
D : 4.2V typ.
I : 2.9V typ.
E : 3.9V typ.
J : 2.7V typ.
F : 3.6V typ.
K : 2.5V typ.
G : 3.3V typ.
L : 2.3V typ.
System Reset PST596~598
MITSUMI
Equivalent Circuit Diagram
Pin Assignment
5
4
1
2
3
1
M/R
2
SUB
3
GND
4
VOUT
5
VCC
SOT-25
Pin Description
Pin No.
Pin name
Function
1
M/R
Manual reset pin
2
SUB
SUB pin
3
GND
GND pin
4
VOUT
Reset signal output pin
5
VCC
Power supply pin/Voltage detection pin
*1
*2
*1: Note that the oscilloscope may mis-operate if the M/R pin falls below -0.3V.
*2: Connect to GND.
Absolute Maximum Ratings
(Ta=25°C)
Item
Symbol
Rating
Units
Storage temperature
TSTG
-40~+125
°C
Operating temperature
TOPR
-20~+75
°C
Power supply voltage
VCC max.
-0.3~+12
V
Manual reset input voltage
VRES max.
-0.3~+12
V
Allowable loss
Pd
150
mW
System Reset PST596~598
MITSUMI
Recommended Operating Conditions
Item
Symbol
Rating
Units
Operating temperature
TOPR
-20~+75
°C
Power supply voltage
VCC
-0.3~+12
V
Electrical Characteristics
Item
(Ta=25°C)
Symbol Measuring circuit
Measurement conditions
VCC=H L
Detection voltage
Vs
1
RL=470Ω
VOL <= 0.4V
C
4.3
4.5
4.7
D
4.0
4.2
4.4
E
3.7
3.9
4.1
F
3.4
3.6
3.8
G
3.1
3.3
3.5
H
2.9
3.1
3.3
I
2.75 2.90 3.05
J
2.55 2.70 2.85
K
2.35 2.50 2.65
L
2.15 2.30 2.45
1
VCC=L
Vs/ T
1
RL=470Ω, Ta=-20°C~+75°C
±0.01
Low-level output voltage
VOL
1
VCC=Vs min. -0.05V, RL=470Ω
0.1
Output leakage current
IOH
1
VCC=10V
Circuit current while on
ICCL
1
VCC=Vs min. -0.05V, RL=∞
Circuit current while off
ICCH
1
VCC=Vs typ./0.85V, RL=∞
Hysteresis voltage
Detection voltage
temperature coefficient
"H" transport delay time
Vs
Min. Typ. Max. Units
TPLH
2
H
L, RL=470Ω
100
0.4
V
±0.1
µA
300
500
µA
15
25
µA
30
50
75
CL=100pF
PST597
60
100
150
*1
PST598
120
200
300
2
Operating power supply voltage
VOPL
1
RL=4.7kΩ, VOL <= 0.4V
Output current while on 1
IOL1
1
VCC=Vs min. -0.05V, RL=0
Output current while on 2
IOL2
1
M/R pin input H voltage
VRESH
M/R pin input H current
IRESH
M/R pin input low voltage
VRESL
RL=4.7kΩ, CL=100pF,
*2
VCC=Vs min. -0.05V, RL=0
Ta=-20~+75°C
mV
%/°C
PST596
TPHL
TPLH ; VCC= (Vs typ.-0.4V) (Vs typ.+0.4V)
TPLH ; VCC= (Vs typ.+0.4V) (Vs typ.-0.4V)
Note 3: Connect manual reset pin to GND when not using.
50
RL=4.7kΩ
"L" transport delay time
*1 :
*2 :
30
V
20
mS
µS
0.65 0.85
V
8
mA
6
mA
2.0
V
VRESH=2.0V
10
-0.3
60
µA
0.8
V
System Reset PST596~598
MITSUMI
Measuring Circuit
[1]
[2]
INPUT PULSE
VS typ
VS typ
+0.4V
-0.4V
0V
Timing Chart
V
VS
VCC
VS
V
VOUT
TPLH
TPLH
TPLH
V
VRES
M/R
Time
System Reset PST596~598
MITSUMI
Application circuits
1. Normal hard reset
Note: Connect a capacitor between IC VCC and GND
pins if VCC line impedance is high.
2. Manual reset
VOUT pin low for manual switch ON.
VOUT pin high for manual switch OFF.
: Mount a clamp diode if it is possible that the M/R
pin might go below -0.3V.
*
Characteristics
VCC VS VOUT
VOUT
VS
VS
VCC