DALLAS DS1233-5

DS1833
5V EconoReset
www.dalsemi.com
FEATURES
PIN ASSIGNMENT
Automatically restarts microprocessor after
power failure
Maintains active-high reset for 350 ms after
VCC returns to an in-tolerance condition
Accurate 5%, 10% or 15% microprocessor 5V
power supply monitoring
Reduces need for discrete components
Precision temperature-compensated voltage
reference and voltage sensor
Low-cost TO-92 package or surface mount
SOT-223 package
Internal 5k pull-up resistor
Operating temperature of -40°C to +85°C
DALLAS
DS1833
1
1 2 3
1 2 3
TO-92 PACKAGE
See Mech.
Drawings Section
2 4 3
SOT-223 PACKAGE
See Mech.
Drawings Section
PIN DESCRIPTION
PIN 1
PIN 2
PIN 3
PIN 4
Ground
Reset
VCC
Ground (SOT-223 only)
DESCRIPTION
The DS1833 EconoReset uses a precision temperature compensated reference and comparator circuit to
monitor the status of the power supply (VCC). When an out-of-tolerance condition is detected, an internal
power fail signal is generated which forces reset to the active (high) state. When VCC returns to an intolerance condition, the reset signal is kept in the active state for approximately 350 ms to allow the
power supply and processor to stabilize.
OPERATION - POWER MONITOR
The DS1833 provides the functions of detecting out-of-tolerance power supply conditions and warning a
processor-based system of impending power failure. When VCC is detected as out-of-tolerance, as
defined by the tolerance of the part selected, the RST signal is asserted. On power-up, RST is kept active
for approximately 350 ms after the power supply has reached the selected tolerance. This allows the
power supply and microprocessor to stabilize before RST is released.
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112099
DS1833
BLOCK DIAGRAM Figure 1
APPLICATION EXAMPLE Figure 2
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DS1833
POWER-UP Figure 3
POWER-DOWN Figure 4
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DS1833
ABSOLUTE MAXIMUM RATINGS*
Voltage on VCC Pin Relative to Ground
Voltage on I/O Relative to Ground
Operating Temperature
Storage Temperature
Soldering Temperature
*
-0.5V to +7.0V
-0.5V to VCC +0.5V
-40°C to +85°C
-55°C to +125°C
260°C for 10 seconds
This is a stress rating only and functional operation of the device at these or any other conditions
above those indicated in the operation sections of this specification is not implied. Exposure to
absolute maximum rating conditions for extended periods of time may affect reliability.
RECOMMENDED DC OPERATING CONDITIONS
(-40°C to +85°C)
PARAMETER
SYMBOL
MIN
TYP
MAX
UNITS
NOTES
Supply Voltage
VCC
1.2
5.0
5.5
V
1
(-40°C to +85°C; VDD=5V ± 10%)
DC ELECTRICAL CHARACTERISTICS
PARAMETER
SYMBOL
Low Level @ RST
VOL
Output Current @ 0.4V
IOL
Operating Current
ICC
VCC Trip Point 5%
VCCTP1
VCC Trip Point 10%
MIN
TYP
MAX
UNITS
NOTES
0.4
V
1
+8
mA
1.5
2
mA
4.5
4.625
4.74
V
1
VCCTP2
4.25
4.375
4.49
V
1
VCC Trip Point 15%
VCCTP3
4.0
4.125
4.24
V
1
Output Capacitance
COUT
10
pF
6.25
kΩ
Internal Pull-Up Resistor
RP
3.75
(-40°C to +85°C; VCC=5V ± 10%)
AC ELECTRICAL CHARACTERISTICS
PARAMETER
5
SYMBOL
MIN
TYP
MAX
UNITS
Reset Active Time
tRST
250
350
450
ms
VCC Detect to RST
tRPD
100
ns
VCC Slew Rate (4.75V - 4.00V)
tF
300
µs
VCC Slew Rate (4.00V - 4.75V)
tR
0
ns
tRPU
250
VCC Detect to RST
NOTES:
1. All voltages are referenced to ground.
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350
450
ms
NOTES
DS1833
ECONORESET SELECTION GUIDE
VCC TRIP POINT
5V
3.3V
PUSHBUTTON DETECT
MIN
TYP
MAX
MIN
TYP
MAX
DS1233-15
4.0
4.125
4.24
2.4
-
3.3
DS1233-10
4.25
4.375
4.49
2.4
-
3.3
DS1233-5
4.5
4.625
4.75
2.4
-
3.3
DS1233D-15
4.0
4.125
4.24
N/A
N/A
DS1233D-10
4.25
4.375
4.49
N/A
N/A
DS1233D-5
4.5
4.625
4.75
N/A
N/A
DS1833-15
4.0
4.125
4.24
N/A
N/A
DS1833-10
4.25
4.375
4.49
N/A
N/A
DS1833-5
4.5
4.625
4.75
N/A
N/A
DS1233A-15
2.64
2.72
2.80
1.8
-
3.0
DS1233A-10
2.8
2.88
2.97
1.8
-
3.0
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