Datasheet DS1816R-5-T-R, DS1816R-20-T-R, DS1816R-10-T-R, DS1816-5, DS1816-20 Datasheet (Dallas Semiconductor)

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FEATURES

 Automatically restarts a microprocessor after

power failure

 Maintains reset for 150 ms after VCC returns

to an in-tolerance condition

 Reduces need for discrete components
 Precision temperature-compensated voltage

reference and voltage sensor

 Accurate 5%, 10% or 20% power monitoring
 20% tolerance for use with 3.0-volt systems
 Low-cost TO-92 or space saving SOT-23

packages available

 Efficient open-drain output with internal

5 kΩ=pull-up resistor

 Operating temperature -40°C to +85°C

PIN ASSIGNMENT

PIN DESCRIPTION
TO-92

1 RST Active Low Reset Output
2 VCC Power Supply
3 GND Ground

SOT-23

1 RST Active Low Reset Output
2 V

CC

Power Supply

3 GND Ground

DESCRIPTION

The DS1816 EconoReset uses a precision temperature reference and comparator circuit to monitor the
status of the power supply (VCC). When an out-of-tolerance condition is detected, an intern al power-fail
signal is generated which forces reset to t he active state. When V

CC

returns to an in-tolerance condition,
the reset signal is kept in the active state for approximately 150 ms to allow the power supply and
processor to stabilize.

DS1816

3.3V EconoReset with
Open Drain Output

www.dalsemi.com

12

3

SOT-23 PACKAGE

1 2 3

1 2 3

TO-92 PACKAGE

See Mech.

Drawings Section

DS1816

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OPERATION - POWER MONITOR

The DS1816 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, the RST
signal is asserted. On power-up, RST is kept active for approximately 150 ms after the power suppl y has
reached the selected tolerance. This allows the power supply and microprocessor to stabilize befor e RST

is released.

BLOCK DIAGRAM (OPEN-DRAIN OUTPUT) Figure 1

APPLICATION EXAMPLE Figure 2

DS1816

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TIMING DIAGRAM: POWER-UP Figure 3

TIMING DIAGRAM: POWER-DOWN Figure 4

DS1816

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ABSOLUTE MAXIMUM RATINGS*

Voltage on VCC Pin Relative to Ground -0.5V to +7.0V
Voltage on RST Relative to Ground -0.5V to VCC +0.5V

Operating Temperature -40°C to +85°C
Storage Temperature -55°C to +125°C
Soldering Temperature 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 V

CC

0.0 5.5 V 1

DC ELECTRICAL CHARACTERISTICS (-40°C to +85°C; VCC=1.2V to 5.5V)

PARAMETER SYMBOL MIN TYP MAX UNITS NOTES

Output Current @ 0.4 V I

OL

+10 mA 2, 3

Operating Current VCC < 5.5V I

CC

28 35

µA

4

VCC Trip Point (DS1816-5) V

CCTP

2.98 3.06 3.15 V 1

VCC Trip Point (DS1816-10) V

CCTP

2.80 2.88 2.97 V 1

VCC Trip Point (DS1816-15) V

CCTP

2.47 2.55 2.64 V 1

Internal Pull-Up Resistor R

P

3.5 5.5 7.5

kΩ

7

Output Capacitance C

OUT

10 pF

AC ELECTRICAL CHARACTERISTICS (-40°C to +85°C; VCC=1.2V to 5.5V)

PARAMETER SYMBOL MIN TYP MAX UNITS NOTES

RESET Active Time t

RST

100 150 250 ms 5

VCC Detect to RST

t

RPD

25

µs

V

CC

Slew Rate

(V

CCTP

(MAX) to V

CCTP

(MIN))

t

F

300

µs

8

VCC Slew Rate
(V

CCTP

(MIN) to V

CCTP

(MAX))

t

R

0ns

VCC Detect to RST

t

RPU

100 150 250 ms 5, 6

DS1816

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NOTES:

1. All voltages are referenced to ground.

2. Measured with VCC ≥ 2.7V.

3. A 1kΩ=external pull-up resistor may be required in some applications for proper operation of the

microprocessor reset control circuit.

4. Measured with RST output open.

5. Measured with 2.7V ≤ VCC ≤ 3.3V.

6. tR = 5 µs.

7. VOH and IOH are a function of the value of RP and the associated output load conditions.

8. The tF value is for reference in defining values for T

RPD

and should not be considered a requirement

for proper operation or use of the device.

PART MARKING CODES

“A”, “B”, &“C” represent the device type.

810 . . . . DS1810

811 . . . . DS1811

812 . . . . DS1812

813 . . . . DS1813

815 . . . . DS1815

816 . . . . DS1816

817 . . . . DS1817

818 . . . . DS1818

“D” represents the device tolerance.

A . . . . . . 5%

B . . . . . . 10%

C . . . . . . 15%

D . . . . . . 20%