Dallas DS1833-5 5v econoreset Datasheet

DS1233D
5V EconoReset
www.maxim-ic.com
FEATURES
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PIN ASSIGNMENT
Automatically restarts microprocessor after
power failure
Maintains 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 5 kW pull-up resistor
Compatible with Motorola 68XXX series and
HC16 Microprocessors
Operating temperature of -40°C to +85°C
1
DALLAS
DS1233
Econo
Reset
2
4
3
TOP VIEW
SOT-23 PACKAGE
See Mech.
Drawings Section
On Website
1 2 3
1 2 3
BOTTOM VIEW
TO-92 PACKAGE
See Mech.
Drawings Section
On Website
PIN DESCRIPTION
PIN 1
PIN 2
PIN 3
PIN 4
GROUND
RESET
VCC
GROUND (SOT-223 ONLY)
DESCRIPTION
The DS1233D 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 state. When VCC returns to an in-tolerance
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 DS1233D 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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041002
DS1233D
BLOCK DIAGRAM Figure 1
APPLICATION EXAMPLE Figure 2
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DS1233D
POWER UP Figure 3
POWER DOWN Figure 4
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DS1233D
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
VOL
MIN
Output Current @ 0.4V
IOL
+8
Operating Current
ICC
VCC Trip Point 5%
VCCTP1
4.5
VCC Trip Point 10%
VCCTP2
VCC Trip Point 15%
VCCTP3
Output Capacitance
COUT
Low Level @ RST
Internal Pull-Up Resistor
RP
SYMBOL
tRST
VCC Detect to RST
tRPD
MAX
0.4
UNITS
V
NOTES
1
mA
2
50
mA
4.625
4.74
V
1
4.25
4.375
4.49
V
1
4.0
4.125
4.24
V
1
10
pF
6.25
kW
3.75
5
(-40°C to +85°C; VCC=5V ± 10%)
AC ELECTRICAL CHARACTERISTICS
PARAMETER
Reset Active Time
TYP
MIN
250
TYP
350
MAX
450
UNITS
ms
100
ns
VCC Slew Rate (4.75V - 4.00V)
tF
300
ms
VCC Slew Rate (4.00V - 4.75V)
tR
0
ns
tRPU
250
VCC Detect to RST
350
450
NOTES
ms
NOTES:
1. All voltages are referenced to ground.
2. A 1 kW external resistor may be required for proper operation of the microprocessor reset control
circuit.
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DS1233D
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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