DS1815-5/T&R - Hytronics

1 of 5 041002

FEATURES

§ Automatically restarts a microprocessor after

power failure

§ Maintains reset for 150ms 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

§ Low-cost TO-92 or space saving surface-

mount SOT-23 packages available

§ Push-pull output for low current operation

§ 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 VCC Power Supply

3 GND Ground

DESCRIPTION

The DS1815 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 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 150ms to allow the power supply and

processor to stabilize.

DS1815

3.3V EconoReset with Push-Pull Output

www.maxim-ic.com

TOP VIEW

SOT-23 PACKAGE

See Mech.

Drawings Section

On Website

1 2 3

BOTTOM VIEW

TO-92 PACKAGE

See Mech.

Drawings Section

On Website

DALLAS

DS1815

Econo

Reset

DS1815

2 of 5

OPERATION — POWER MONITOR

The DS1815 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 150ms after the power supply has

reached the selected tolerance. This allows the power supply and microprocessor to stabilize before RST

is released.

BLOCK DIAGRAM (CMOS OUTPUT) Figure 1

APPLICATION EXAMPLE Figure 2

APPLICATION DIAGRAM:

RST VALID TO 0 VOLTS VCC ON THE DS1815 Figure 3

DS1815

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TIMING DIAGRAM: POWER-UP Figure 4

TIMING DIAGRAM: POWER-DOWN Figure 5

DS1815

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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 +5VCC +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 VCC 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 Voltage @ -500mAVOH VCC

-0.5V

VCC

-0.1V

Output Current @ 2.4V IOH 350 mA2

Output Current @ 0.4V IOL +10 mA 2

Operating Current VCC < 5.5 ICC 28 35 mA3

VCC Trip Point (DS1815-5) VCCTP 2.98 3.06 3.15 V 1

VCC Trip Point (DS1815-10) VCCTP 2.80 2.88 2.97 V 1

VCC Trip Point (DS1815-20) VCCTP 2.47 2.55 2.64 V 1

Output Capacitance COUT 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 tRST 100 150 250 ms 4

VCC Detect to RST tRPD 25 ms

VCC Slew Rate

(VCCTP (MAX) to VCCTP (MIN))

tF300 ms6

VCC Slew Rate

(VCCTP (MIN) to VCCTP (MAX))

tR0ns

VCC Detect to RST tRPU 100 150 250 ms 4, 5

DS1815

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NOTES:

1. All voltages are referenced to ground.

2. Measured with VCC ³ 2.7V.

3. Measured with RST output open.

4. Measured with 2.7V £ VCC £ 3.3V.

5. tR = 5ms.

6. The tF value is for reference in defining values for TRPD 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%

ENGLISH • ???? • ??? • ???

WHAT'S NEW

PRODUCTS

SOLUTIONS

DESIGN

APPNOTES

SUPPORT

BUY

COMPANY

MEMBERS

DS1815

Part Number Table

Notes:

See the DS1815 QuickView Data Sheet for further information on this product family or download the DS1815 full data sheet

(PDF, 128kB).

Other options and links for purchasing parts are listed at: http://www.maxim-ic.com/sales.2.

Didn't Find What You Need? Ask our applications engineers. Expert assistance in finding parts, usually within one business day.3.

Part number suffixes: T or T&R = tape and reel; + = RoHS/lead-free; # = RoHS/lead-exempt. More: See full data sheet or Part

Naming Conventions.

* Some packages have variations, listed on the drawing. "PkgCode/Variation" tells which variation the product uses.5.

Part Number

Notes

Free

Sample

Buy

Direct

Package:

TYPE PINS SIZE

DRAWING CODE/VAR *

Temp

RoHS/Lead-Free?

Materials Analysis

DS1815R-5-U+

SOT23;3 pin;50

Dwg: 21-0051G (PDF)

Use pkgcode/variation: U3+4*

-40C to +85C

RoHS/Lead-Free: Yes

Materials Analysis

DS1815R-20+T&R

3.3V-

20%

SOT23;3 pin;50

Dwg: 21-0051G (PDF)

Use pkgcode/variation: U3+4*

-40C to +85C

RoHS/Lead-Free: Yes

Materials Analysis

DS1815R-5+T&R

3.3V-5%

SOT23;3 pin;50

Dwg: 21-0051G (PDF)

Use pkgcode/variation: U3+4*

-40C to +85C

RoHS/Lead-Free: Yes

Materials Analysis

DS1815R-20-U

3.3V-

20%

SOT23;3 pin;50

Dwg: 21-0051G (PDF)

Use pkgcode/variation: U3-4*

-40C to +85C

RoHS/Lead-Free: No

Materials Analysis

DS1815R-10-U

3.3V-

10%

SOT23;3 pin;50

Dwg: 21-0051G (PDF)

Use pkgcode/variation: U3-4*

-40C to +85C

RoHS/Lead-Free: No

Materials Analysis

DS1815R-5-U

3.3V-5%

SOT23;3 pin;50

Dwg: 21-0051G (PDF)

Use pkgcode/variation: U3-4*

-40C to +85C

RoHS/Lead-Free: No

Materials Analysis

DS1815R-20/T&R

3.3V-

20%

Tolerance

SOT23;3 pin;50

Dwg: 21-0051G (PDF)

Use pkgcode/variation: U3-4*

-40C to +85C

RoHS/Lead-Free: No

Materials Analysis

DS1815R-10/T&R

3.3V-

10%

Tolerance

SOT23;3 pin;50

Dwg: 21-0051G (PDF)

Use pkgcode/variation: U3-4*

-40C to +85C

RoHS/Lead-Free: No

Materials Analysis

DS1815R-5/T&R

3.3V-5%

SOT23;3 pin;50

Dwg: 21-0051G (PDF)

Use pkgcode/variation: U3-4*

-40C to +85C

RoHS/Lead-Free: No

Materials Analysis

DS1815R-10-U+

SOT23;3 pin;50

Dwg: 21-0051G (PDF)

Use pkgcode/variation: U3+4*

-40C to +85C

RoHS/Lead-Free: Yes

Materials Analysis

DS1815R-20-U+

SOT23;3 pin;50

Dwg: 21-0051G (PDF)

Use pkgcode/variation: U3+4*

-40C to +85C

RoHS/Lead-Free: Yes

Materials Analysis

DS1815R-10+T&R

3.3V-

10%

SOT23;3 pin;50

Dwg: 21-0051G (PDF)

Use pkgcode/variation: U3+4*

-40C to +85C

RoHS/Lead-Free: Yes

Materials Analysis

DS1815-10+T&R

3.3V-

10%

TO92;3 pin;185

Dwg: 56-G0006-003A (PDF)

Use pkgcode/variation: Q3+4*

-40C to +85C

RoHS/Lead-Free: Yes

Materials Analysis

DS1815-20+T&R

3.3V-

20%

TO92;3 pin;185

Dwg: 56-G0006-003A (PDF)

Use pkgcode/variation: Q3+4*

-40C to +85C

RoHS/Lead-Free: Yes

Materials Analysis

DS1815-5+T&R

3.3V-5%

TO92;3 pin;185

Dwg: 56-G0006-003A (PDF)

Use pkgcode/variation: Q3+4*

-40C to +85C

RoHS/Lead-Free: Yes

Materials Analysis

DS1815-20/T&R

3.3V-

20%

TO92;3 pin;185

Dwg: 56-G0006-003A (PDF)

Use pkgcode/variation: Q3-4*

-40C to +85C

RoHS/Lead-Free: No

Materials Analysis

DS1815-10/T&R

3.3V-

10%

TO92;3 pin;185

Dwg: 56-G0006-003A (PDF)

Use pkgcode/variation: Q3-4*

-40C to +85C

RoHS/Lead-Free: No

Materials Analysis

DS1815-5/T&R

3.3V-5%

TO92;3 pin;185

Dwg: 56-G0006-003A (PDF)

Use pkgcode/variation: Q3-4*

-40C to +85C

RoHS/Lead-Free: No

Materials Analysis

DS1815-20

3.3V-

20%

Monitor

TO92;3 pin;185

Dwg: 56-G0006-001A (PDF)

Use pkgcode/variation: Q3-1*

-40C to +85C

RoHS/Lead-Free: No

Materials Analysis

DS1815-10

3.3V-

10%

Monitor

TO92;3 pin;185

Dwg: 56-G0006-001A (PDF)

Use pkgcode/variation: Q3-1*

-40C to +85C

RoHS/Lead-Free: No

Materials Analysis

DS1815-5

3.3V-5%

Monitor

TO92;3 pin;185

Dwg: 56-G0006-001A (PDF)

Use pkgcode/variation: Q3-1*

-40C to +85C

RoHS/Lead-Free: No

Materials Analysis

DS1815-5+

TO92;3 pin;185

Dwg: 56-G0006-001A (PDF)

Use pkgcode/variation: Q3+1*

-40C to +85C

RoHS/Lead-Free: Yes

Materials Analysis

DS1815-10+

TO92;3 pin;185

Dwg: 56-G0006-001A (PDF)

Use pkgcode/variation: Q3+1*

-40C to +85C

RoHS/Lead-Free: Yes

Materials Analysis

DS1815-20+

TO92;3 pin;185

Dwg: 56-G0006-001A (PDF)

Use pkgcode/variation: Q3+1*

-40C to +85C

RoHS/Lead-Free: Yes

Materials Analysis

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