U6808B-MFP

U6808B-MFP Datasheet

The U6808B is designed to support the fail-safe function of a safety critical system e.g., ABS . It includes a relay driver, a watchdog controlled by an external R/C-network and a reset circuit initiated by an over and undervoltage condition of the 5-V supply providing a low-level reset signal.

Part	Datasheet
U6808B-MFP	U6808B-MFP (pdf)

Related Parts	Information
U6808B-MFPG3Y	U6808B-MFPG3Y
U6808B-MFPY	U6808B-MFPY
U6808B-MFPG3	U6808B-MFPG3

PDF Datasheet Preview
• Digital Self-supervising Watchdog with Hysteresis • One 250-mA Output Driver for Relay • Enable Output Open Collector 8 mA • Over/Undervoltage Detection • ENABLE and RELAY Outputs Protected Against Standard Transients and 40 V Load Dump • ESD Protection According to MIL-STD-883 D Test Method Human Body Model ±2 kV 100 pF, kW Machine Model ±200 V 200 pF, 0 W The U6808B is designed to support the fail-safe function of a safety critical system e.g., ABS . It includes a relay driver, a watchdog controlled by an external R/C-network and a reset circuit initiated by an over and undervoltage condition of the 5-V supply providing a low-level reset signal. Figure Block Diagram Bandgap reference Power-on reset Reset debounce Reset delay VS RESET RELAY Special Fail-safe IC U6808B Under/ overvoltage detection RIN WDI ENABLE Internal oscillator Current limitation Watchdog RC oscillator Pin Configuration Figure Pinning SO8 RELAY 1 ENABLE 3 8 VS 7 RIN 6 WDI 5 RESET Pin Description RELAY ENABLE RESET Type Open collector driver output Supply Digital output Analog input Digital output Digital input Digital input Supply Function Fail-safe relay driver Standard ground Negative reset signal External RC for watchdog timer Negative reset signal Watchdog trigger signal Activation of relay driver 5-V supply Logic No signal driver off Low driver on No signal Low reset No signal Low reset Pulse sequence High driver on Low driver off Fail-safe Functions A fail-safe IC has to maintain its monitoring function even if there is a fault condition at one of the pins e.g., short circuit . This ensures that a microcontroller system is not brought into a critical status. A critical status is reached if the system is not able to switch off the relay and to give a signal to the microcontroller via the ENABLE and RESET outputs. The following table shows the fault conditions for the pins. Ordering Information Extended Type Number U6808B Package Information Package SO8 Remarks Package SO8 Dimensions in mm U6808B technical drawings according to DIN specifications Atmel Headquarters Corporate Headquarters 2325 Orchard Parkway San Jose, CA 95131 TEL 1 408 441-0311 FAX 1 408 487-2600 Europe Atmel Sarl Route des Arsenaux 41 Case Postale 80 CH-1705 Fribourg Switzerland TEL 41 26-426-5555 FAX 41 26-426-5500 Asia Room 1219 Chinachem Golden Plaza 77 Mody Road Tsimhatsui East Kowloon Hong Kong TEL 852 2721-9778 FAX 852 2722-1369 Japan 9F, Tonetsu Shinkawa Bldg. 1-24-8 Shinkawa Chuo-ku, Tokyo 104-0033 Japan TEL 81 3-3523-3551 FAX 81 3-3523-7581 Atmel Operations Memory 2325 Orchard Parkway San Jose, CA 95131 TEL 1 408 441-0311 FAX 1 408 436-4314 Microcontrollers 2325 Orchard Parkway San Jose, CA 95131 TEL 1 408 441-0311 FAX 1 408 436-4314 La Chantrerie BP 70602 44306 Nantes Cedex 3, France TEL 33 2-40-18-18-18 FAX 33 2-40-18-19-60 ASIC/ASSP/Smart Cards Zone Industrielle 13106 Rousset Cedex, France TEL 33 4-42-53-60-00 FAX 33 4-42-53-60-01 1150 East Cheyenne Mtn. Blvd. Colorado Springs, CO 80906 TEL 1 719 576-3300 FAX 1 719 540-1759 Scottish Enterprise Technology Park Maxwell Building East Kilbride G75 0QR, Scotland TEL 44 1355-803-000 FAX 44 1355-242-743 RF/Automotive Theresienstrasse 2 Postfach 3535 74025 Heilbronn, Germany TEL 49 71-31-67-0 FAX 49 71-31-67-2340 1150 East Cheyenne Mtn. Blvd. Colorado Springs, CO 80906 TEL 1 719 576-3300 FAX 1 719 540-1759 Biometrics/Imaging/Hi-Rel MPU/ High Speed Converters/RF Datacom Avenue de Rochepleine BP 123 38521 Saint-Egreve Cedex, France TEL 33 4-76-58-30-00 FAX 33 4-76-58-34-80 e-mail Web Site Atmel Corporation Atmel Corporation makes no warranty for the use of its products, other than those expressly contained in the Company’s standard warranty which is detailed in Atmel’s Terms and Conditions located on the Company’s web site. The Company assumes no responsibility for any errors which may appear in this document, reserves the right to change devices or specifications detailed herein at any time without notice, and does not make any commitment to update the information contained herein. No licenses to patents or other intellectual property of Atmel are granted by the Company in connection with the sale of Atmel products, expressly or by implication. Atmel’s products are not authorized for use as critical components in life support devices or systems. is the registered trademark of Atmel. Other terms and product names may be the trademarks of others. Printed on recycled paper.

PDF Datasheet Preview

• Digital Self-supervising Watchdog with Hysteresis
• One 250-mA Output Driver for Relay
• Enable Output Open Collector 8 mA
• Over/Undervoltage Detection
• ENABLE and RELAY Outputs Protected Against Standard Transients
and 40 V Load Dump
• ESD Protection According to MIL-STD-883 D Test Method

Human Body Model ±2 kV 100 pF, kW Machine Model ±200 V 200 pF, 0 W

The U6808B is designed to support the fail-safe function of a safety critical system e.g., ABS . It includes a relay driver, a watchdog controlled by an external R/C-network and a reset circuit initiated by an over and undervoltage condition of the 5-V supply providing a low-level reset signal.

Figure Block Diagram

Bandgap reference

Power-on reset

Reset debounce

Reset delay

VS RESET RELAY

Special Fail-safe IC

U6808B

Under/ overvoltage detection

RIN WDI

ENABLE

Internal oscillator

Current
limitation

Watchdog

RC oscillator

Pin Configuration

Figure Pinning SO8

RELAY 1

ENABLE 3
8 VS 7 RIN 6 WDI 5 RESET

Pin Description

RELAY

ENABLE

RESET

Type Open collector driver output

Supply Digital output Analog input Digital output Digital input

Digital input

Supply

Function

Fail-safe relay driver

Standard ground Negative reset signal External RC for watchdog timer Negative reset signal Watchdog trigger signal

Activation of relay driver
5-V supply

Logic No signal driver off Low driver on No signal Low reset No signal Low reset Pulse sequence High driver on Low driver off

Fail-safe Functions

A fail-safe IC has to maintain its monitoring function even if there is a fault condition at one of the pins e.g., short circuit . This ensures that a microcontroller system is not brought into a critical status. A critical status is reached if the system is not able to switch off the relay and to give a signal to the microcontroller via the ENABLE and RESET outputs. The following table shows the fault conditions for the pins.
Ordering Information

Extended Type Number U6808B

Package Information

Package SO8

Remarks

Package SO8

Dimensions in mm

U6808B
technical drawings according to DIN specifications

Atmel Headquarters

Corporate Headquarters 2325 Orchard Parkway San Jose, CA 95131 TEL 1 408 441-0311 FAX 1 408 487-2600

Europe Atmel Sarl Route des Arsenaux 41 Case Postale 80 CH-1705 Fribourg Switzerland TEL 41 26-426-5555 FAX 41 26-426-5500

Asia Room 1219 Chinachem Golden Plaza 77 Mody Road Tsimhatsui East Kowloon Hong Kong TEL 852 2721-9778 FAX 852 2722-1369

Japan 9F, Tonetsu Shinkawa Bldg. 1-24-8 Shinkawa Chuo-ku, Tokyo 104-0033 Japan TEL 81 3-3523-3551 FAX 81 3-3523-7581

Atmel Operations

Memory 2325 Orchard Parkway San Jose, CA 95131 TEL 1 408 441-0311 FAX 1 408 436-4314

Microcontrollers 2325 Orchard Parkway San Jose, CA 95131 TEL 1 408 441-0311 FAX 1 408 436-4314

La Chantrerie BP 70602 44306 Nantes Cedex 3, France TEL 33 2-40-18-18-18 FAX 33 2-40-18-19-60

ASIC/ASSP/Smart Cards Zone Industrielle 13106 Rousset Cedex, France TEL 33 4-42-53-60-00 FAX 33 4-42-53-60-01
1150 East Cheyenne Mtn. Blvd. Colorado Springs, CO 80906 TEL 1 719 576-3300 FAX 1 719 540-1759

Scottish Enterprise Technology Park Maxwell Building East Kilbride G75 0QR, Scotland TEL 44 1355-803-000 FAX 44 1355-242-743

RF/Automotive Theresienstrasse 2 Postfach 3535 74025 Heilbronn, Germany TEL 49 71-31-67-0 FAX 49 71-31-67-2340 1150 East Cheyenne Mtn. Blvd. Colorado Springs, CO 80906 TEL 1 719 576-3300 FAX 1 719 540-1759

Biometrics/Imaging/Hi-Rel MPU/ High Speed Converters/RF Datacom

Avenue de Rochepleine BP 123 38521 Saint-Egreve Cedex, France TEL 33 4-76-58-30-00 FAX 33 4-76-58-34-80
e-mail Web Site

Atmel Corporation Atmel Corporation makes no warranty for the use of its products, other than those expressly contained in the Company’s standard warranty which is detailed in Atmel’s Terms and Conditions located on the Company’s web site. The Company assumes no responsibility for any errors which may appear in this document, reserves the right to change devices or specifications detailed herein at any time without notice, and does not make any commitment to update the information contained herein. No licenses to patents or other intellectual property of Atmel are granted by the Company in connection with the sale of Atmel products, expressly or by implication. Atmel’s products are not authorized for use as critical components in life support devices or systems.
is the registered trademark of Atmel. Other terms and product names may be the trademarks of others.

Printed on recycled paper.

Notice: we do not provide any warranties that information, datasheets, application notes, circuit diagrams, or software stored on this website are up-to-date or error free. The archived U6808B-MFP Datasheet file may be downloaded here without warranties.

Datasheet ID: U6808B-MFP 519520