Zetex ZSM300N8, ZSM300C, ZSM300G Datasheet

SUPPLY VOLTAGE
MONITOR

ISSUE 1 – NOVEMBER 1995

ZSM300

DEVICE DESCRIPTION

The ZSM300 is a three terminal under
voltage monitor circuit for use in
microprocessor systems. The threshold
voltage of the device has been set to 2.63
volts making it ideal for 3 volt circuits.

Included in the device is a precise voltage
reference and a comparator with built in
hysteresis to prevent erratic operation. The
ZSM300 features an open collector output
capable of sinking 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
low 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 low.

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

2.63 volt threshold for 3 volt logic

•

20mV hysteresis prevents erratic operation

•

APPLICATIONS

Microprocessor systems

•

Computers

•

Computer peripherals

•

Instrumentation

•

Automotive

•

Battery powered equipment

•

4-339

ZSM300

ABSOLUTE MAXIMUM RATING

Input Supply Voltage -1 to 10V
Offstate Output Voltage 10V
Onstate Output

Sink Current(

Note 1) Internally limited

Power Dissipation

TO92 780mW
SOT223 2W(

Note 2)

SO8 780mW(

Note 2)

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

=25°C for typical values, T

(T

amb

=-40 to 85°C for min/max values (Note3))

amb

COMPARATOR

PARAMETER SYMBOL
Threshold Voltage

High state output (V

increasing) V

cc

IH

Threshold Voltage
Low state output (V

Hysteresis V

decreasing) V

cc

IL

H

MIN TYP. MAX.

2.56 2.64 2.7 V

2.56 2.62 2.7 V

0.01 0.02 0.05 V

UNITS

OUPUT

Output sink saturation: V

(Vcc=2.2V, I
(V

=2.2V, I

cc

(V

=1.0V, I

cc

=8.0mA) 0.46 1.0 V

sink

=2.0mA) 0.15 0.4 V

sink

=0.1mA) 0.25 V

sink

Onstate output sink current
(V

, Output=2.2V)

cc

Offstate output leakage current
(V

, Output=3V)

cc

Clamp diode forward voltage
(I

=10mA)

f

Propagation delay
(V

3V to 2.2V, Rl=10k, T

in

amb

=25°C)

I

I

V

T

OL

sink

oh

f

d

10 27 60 mA

0.02 0.5

µA

0.6 1.2 1.5 V

2.5

µs

TOTAL DEVICE

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.

=3V) I

cc

cc

q

1.0 to 6.5 V
125 190

µA

4-340