ZETEX ZSH330N8

SUPPLY VOLTAGE
MONITOR
ZSH330
ISSUE 1 - DECEMBER 1997
DEVICE DESCRIPTION
FEATURES
The ZSH330 is a three terminal under voltage
monitor circuit for use in microprocessor
systems. The threshold voltage of the device
has been set to 3.1 volts making it ideal for
3.3 volt circuits.
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Included in the device is a precise voltage
reference and a comparator with built in
hysteresis to prevent erratic operation. The
ZSH330 features an open collector output
capable of sourcing at least l0mA which only
requires a single external resistor to
interface to following circuits.
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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
3.1 volt threshold for 3.3 volt logic
20mV hysteresis prevents erratic operation
APPLICATIONS
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.
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Microprocessor systems
Computers
Computer peripherals
Instrumentation
Automotive
Battery powered equipment
The device is available in a TO92 package for
through hole applications as well as SO8 and
SOT223 for surface mount requirements.
SCHEMATIC DIAGRAM
Vcc
Out
Gnd
4-329
ZSH330
ABSOLUTE MAXIMUM RATING
Input Supply Voltage
Offstate Output Voltage
Onstate Output
Source Current(Note 1)
Clamp Diode
Forward Current(Note 1)
Operating Junction
Temperature
Operating Temperature
Storage Temperature
-1 to 10V
10V
Internally limited
Power Dissipation
TO92
SOT223
SO8
780mW
2W(Note 2)
780mW(Note 2)
100mA
150°C
-40 to 85°C
-55 to 150°C
TEST CONDITIONS
(Tamb=25°C for typical values, Tamb=-40 to 85°C for min/max values (Note3))
COMPARATOR
MIN
TYP.
MAX.
PARAMETER
SYMBOL
UNITS
Threshold Voltage
Low state output (Vcc increasing)
VIL
3.01
3.09
3.15
V
Threshold Voltage
High state output (Vcc decreasing)
VIH
3.01
3.07
3.15
V
Hysteresis
VH
0.01
0.02
0.05
V
OUPUT
PARAMETER
SYMBOL
Output source saturation:
VOH
MIN
TYP.
MAX.
UNITS
(Vcc=2.7V, Isource=8.0mA)
VCC-1.3
V
(Vcc=2.7V, Isource=2.0mA)
VCC-1.2
V
(Vcc=1.0V, Isource=2µA)
VCC-0.4
V
21
50
mA
0.02
0.5
µA
1.2
1.5
V
Onstate output source current
(Vcc=2.7V, Output=0V)
Isource
Offstate output leakage current
(Vcc=3.3V, Output=0V)
Ioh
Clamp diode forward voltage (If=10mA) Vf
Propagation delay
(Vin 3.3V to 2.7V, Rl=10k, Tamb=25°C)
10
0.6
µs
1.4
Td
TOTAL DEVICE
PARAMETER
SYMBOL
Operating input voltage range
Vcc
Quiescent input current (Vcc=3.3V)
Iq
MIN
TYP.
MAX.
1.0 to 6.5
UNITS
V
130
180
µA
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.
4-330
ZSH330
500
5.0
400
4.0
Output Voltage (V)
Input Current (µA)
TYPICAL CHARACTERISTICS
300
200
100
85°C
25°C
-40°C
0
3.0
2.0
1.0
0.0
0
2
4
6
8
10
0.0
Input Voltage (V)
1.0
2.0
3.0
4.0
5.0
Input Voltage (V)
Output Voltage v Input Voltage
Input Current v Input Voltage
Vin(V)
20
85°C
25°C
-40°C
10
0
0.8
0.6
0.4
0.2
0.0
3.3
2.7
2.0
4.0
-40°C
25°C
85°C
Vout(V)
Source Current (mA)
Rl=10k
30
2.0
0.0
0.0
0.4
0.8
1.2
1.6
2.0
0
1
Output Saturation Voltage (V)
100
3.10
80
3.09
85°C
25°C
-40°C
40
20
0
0.0
0.4
0.8
1.2
3
4
Reset Delay Time
Threshold Voltage (V)
Forward Current (mA)
Output Saturation Voltage v
Source Current
60
2
Time (µs)
Upper
Threshold
3.08
Lower
Threshold
3.07
3.06
3.05
-40 -20
1.6
0
20
40
60
80
100
Temperature (°C)
Forward Voltage (V)
Threshold Voltage v Temperature
Clamp Diode Forward Current v Voltage
4-331
ZSH330
TIMING DIAGRAM
APPLICATION CIRCUIT
Note 4: A time delayed reset can be accomplished with
the additional Cd.
TDY =Time (Seconds)
VTH =Microprocessor Reset Threshold
1
  1 


T DY = RCd ln 
(ground referenced)
 − ln 

V
V
  TH 
 1− SAT 
VSAT =Output Saturation Voltage ( from
 V 

V in 
Output Saturation Voltage characteristic)
  in 


Vin =Power Supply Voltage
4-332
ZSH330
CONNECTION DIAGRAMS
SO8 Package Suffix – N8
Top View
SOT223 Package Suffix – G
Top View –
Connect pin 4 to pin 2 or leave pin 4
electrically isolated
TO92 Package Suffix – C
Bottom View
ORDERING INFORMATION
Part No
Package
Partmark
ZSH330C
TO92
ZSH330
ZSH330G
SOT223
ZSH330
ZSH330N8
SO8
ZSH330
4-333