U6808B-MFPY Atmel, U6808B-MFPY Datasheet
U6808B-MFPY
Specifications of U6808B-MFPY
Related parts for U6808B-MFPY
U6808B-MFPY Summary of contents
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... Human Body Model: ±2 kV (100 pF, 1 – Machine Model: ±200 V (200 pF Description 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-net- work and a reset circuit initiated by an over and undervoltage condition of the 5-V supply providing a low-level reset signal ...
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... Supply 3 ENABLE Digital output 4 WDC Analog input 5 RESET Digital output 6 WDI Digital input 7 RIN Digital input 8 VS Supply U6808B 2 RELAY GND ENABLE 3 6 WDC 4 5 Function Fail-safe relay driver Standard ground Negative reset signal External RC for watchdog timer Negative reset signal ...
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... High Off Low Off Low Off Low Off Low Relay Output Driver Enable Output Driver (RELAY) Off On Off Off Off Off U6808B Open Circuit Relay off Watchdog reset Watchdog reset Relay off Enable Output Driver (ENABLE) Off Off (ENABLE) Off Off On ...
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... If the RC oscillator stops oscillating a signal is fed to the OSCERR input after a time-out delay. It resets the up/down counter and dis- ables the WD-OK output. Without this reset function the watchdog would freeze in its current status when f U6808B 4 Watchdog Block Diagram Binary counter ...
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... Bad indicates that a pulse has been received whose width is either too short or too long. 4707B–AUTO–10/05 Watchdog State Diagram good Initial status 1/NF bad bad bad O/F bad good bad 1/F good U6808B Figure 5-2) the RS flip-flop is set and 2/NF good good bad 3/NF good 2/F 5 ...
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... A pulse longer than the debounce time results in the first reset delay pulse appears during this delay, a second delay time is triggered. Therefore, the total reset delay time can be longer than specified in the data sheet. U6808B 6 < 100 k due to leakage current and humidity) osc ...
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... Hz WDC WDI Symbol Min. Typ. Max 1.2 S –0.2 0.2 0 100 – ZWDI –0.2 0.2 0 –5 100 V 20 ZRIN U6808B Unit K/W °C °C °C Unit 5 550 µA +5 µ 0 µA 550 µA ...
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... Reset delay RC Oscillator WDC Oscillator frequency Watchdog Timing Power-on-reset prolongation time Detection time for RC oscillator fault Time interval for over-/undervoltage detection Reaction time of RESET output over/undervoltage U6808B 8 = 100 kHz + 50% – 45%, f intern Test Conditions Pull- 1.2V < V < 16V S Switch to low ...
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... Symbol Min. Typ. Max WDI f 1 WDC t 182 P,WDI f 64.7 112.5 WDI n 3 lock n 3 release t 24.5 WDIerror 250 Duration 2 ms 0.05 ms 0.1s 0.1s 250 ms U6808B Unit 130 Hz 13 kHz µs Hz 25.5 ms Cycles 169 Cycles Cycle 251 Cycles Amount 15.000 15.000 ...
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... Watchdog in Too-fast Condition Normal operation 5 V WDI Batt RELAY ENABLE 0 V Figure 9-2. Watchdog in Too-slow Condition Normal operation 5 V WDI Batt RELAY ENABLE 0 V U6808B 10 WDI too fast Normal operation WDI too slow Don't care Normal operation Don't care 4707B–AUTO–10/05 ...
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... Reset debounce time 4707B–AUTO–10/05 Overvoltage condition > 120 s < 120 s 3 good WDI pulses st 1 Reset delay nd 2 Reset delay Undervoltage condition > 120 s < 120 s 3 good WDI pulses st 1 Reset delay nd 2 Reset delay > 5.6 V Don't care < 4.5 V Don't care U6808B 11 ...
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... Figure 9-5. Application Circuit U6808B 100 0.01 F U6808B Relay C V Batt osc osc 3.3 nF 4707B–AUTO–10/05 ...
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... Ordering Information Extended Type Number U6808B-MFPY U6808B-MFPG3Y 11. Package Information Package SO8 Dimensions in mm 12. Revision History Please note that the following page numbers referred to in this section refer to the specific revision mentioned, not to this document. Revision No. 4707B-AUTO-10/05 4707B–AUTO–10/05 Package Remarks ...
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... Disclaimer: The information in this document is provided in connection with Atmel products. No license, express or implied, by estoppel or otherwise, to any intellectual property right is granted by this document or in connection with the sale of Atmel products. EXCEPT AS SET FORTH IN ATMEL’S TERMS AND CONDI- TIONS OF SALE LOCATED ON ATMEL’S WEB SITE, ATMEL ASSUMES NO LIABILITY WHATSOEVER AND DISCLAIMS ANY EXPRESS, IMPLIED OR STATUTORY WARRANTY RELATING TO ITS PRODUCTS INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT ...