SUPPLY VOLTAGE
MONITOR
ISSUE 1 - MARCH 1998
ZSH560
DEVICE DESCRIPTION
The ZSH560 is a three terminal under voltage
monitor circuit for use in microprocessor
systems. The threshold voltage of the device
has been set to 4.6 volts making it ideal for
5 volt circuits.
Included in the device is a precise voltage
reference and a comparator with built in
hysteresis to prevent erratic operation. The
ZSH560 features an open collector output
capable of sourcing at least l0mA which only
requires a single external resistor to
interface to following circuits.
Operation of the device is guaranteed from
one volt upwards, from this level to the
device threshold voltage the output is held
high providing a power on reset function.
Should the supply voltage, once established,
at any time drop below the threshold level
then the output again will pull high.
The device is available in a TO92 package for
through hole applications as well as SO8 and
SOT223 for surface mount requirements.
SCHEMATIC DIAGRAM
FEATURES
SO8, SOT223 and TO92 packages
•
Power on reset generator
•
Automatic reset generation
•
Low standby current
•
Guaranteed operation from 1 volt
•
Wide supply voltage range
•
Internal clamp diode to discharge
•
delay capacitor
4.6 volt threshold for 5 volt logic
•
20mV hysteresis prevents erratic operation
•
APPLICATIONS
Microprocessor systems
•
Computers
•
Computer peripherals
•
Instrumentation
•
Automotive
•
Battery powered equipment
•
Vcc
Out
Gnd
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ZSH560
ABSOLUTE MAXIMUM RATING
Input Supply Voltage -1 to 10V
Offstate Output Voltage 10V
Onstate Output
Source Current(
Note 1) Internally limited
Clamp Diode
Forward Current(
Note 1) 100mA
Operating Junction
Temperature 150°C
Operating Temperature -40 to 85°C
Storage Temperature -55 to 150°C
TEST CONDITIONS
(T
=25°C for typical values, T
amb
=-40 to 85°C for min/max values (Note3))
amb
COMPARATOR
PARAMETER SYMBOL
Threshold Voltage
Low state output (Vcc increasing) V
IL
Threshold Voltage
High state output (Vcc decreasing) V
Hysteresis V
IH
H
OUPUT
PARAMETER SYMBOL
Output source saturation: V
(Vcc=4.0V, I
(V
=4.0V, I
cc
(V
=1.0V, I
cc
=8.0mA) VCC-1.3 V
source
=2.0mA) VCC-1.2 V
source
=2µA)
source
Onstate output source current
(V
=4.0V, Output=0V)
cc
Offstate output leakage current
(V
=5.0V, Output=0V)
cc
Clamp diode forward voltage (I
=10mA) V
f
Propagation delay
(V
5V to 4V, Rl=10k, T
in
amb
=25°C)
OH
I
source
I
oh
f
T
d
TOTAL DEVICE
PARAMETER SYMBOL
Operating input voltage range V
Quiescent input current (V
Note:
1. Maximum package power dissipation must be observed.
2. Maximum power dissipation, for the SOT223 and SO8 packages, is calculated assuming
that the device is mounted on a PCB measuring 2 inches square.
3. Low duty cycle pulse techniques are used during test to maintain junction temperatures as
close to ambient as possible.
=5V) I
cc
cc
q
Power Dissipation
TO92 780mW
SOT223 2W(
Note 2)
SO8 780mW(
MIN TYP. MAX.
UNITS
4.5 4.61 4.7 V
4.5 4.59 4.7 V
0.01 0.02 0.05 V
MIN TYP. MAX.
V
CC
UNITS
-0.4 V
10 20 50 mA
0.02 0.5
µA
0.6 1.2 1.5 V
1.5
MIN TYP. MAX.
µs
UNITS
1.0 to 6.5 V
135 200
µA
Note 2)
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