U6808B-MFP Atmel, U6808B-MFP Datasheet
U6808B-MFP
Specifications of U6808B-MFP
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U6808B-MFP Summary of contents
Page 1
... Human Body Model: ±2 kV (100 pF, 1.5 kW) – 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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... Function Digital input to RIN activate the fail-safe relay Watchdog trigger WDI input Capacitor and OSC resistor of watchdog Driver of the fail-safe RELAY relay U6808B 2 RELAY 1 2 GND ENABLE 3 WDC 4 Function Fail-safe relay driver Standard ground Negative reset signal External RC for watchdog timer ...
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... Driver (RELAY) (RESET) Off High On High Off Low Off Low Off Low Off Low Relay Output Driver Enable Output Driver (RELAY) Off On Off Off Off Off Dual MUX Up/down RS-FF counter U6808B Enable Output Driver (ENABLE) Off Off (ENABLE) Off Off WD-OK 3 ...
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... RCOSC Input OSCERR Input RESET Input WD-OK Output Watchdog State Diagram U6808B 4 The microcontroller has to provide a trigger signal with the frequency f the WDI input. A positive edge of f counter and clocks the up/down counter additionally. The latter one counts only from reverse. Each correct trigger increments the up/down counter by 1, each wrong trigger decrements ...
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... 0.0005]] osc /169 = 59.1 Hz WDC /170 = 58.8 Hz WDC /79 = 126.6 Hz /80 = 125.0 Hz 170/f 250/f WDC WDC Update rate is too Update rate is slow either too slow or pulse has dropped out U6808B 251/f WDC Pulse has dropped out 5 ...
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... Zener clamping voltage Digital Input RIN Detection low Detection high Resistance to GND Input current low Input current high Zener clamping voltage Digital Output RESET with Internal Pull-up Voltage high Voltage low Zener clamping voltage Reset debounce time U6808B 6 Symbol tot P tot R thja T j ...
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... WDC 103.1 POR t 81.9 246 RCerror t 0.16 0.64 D,OUV t 0.187 0.72 R,OUV f 10 130 WDI f 1 WDC t 182 P,WDI f 64.7 112.5 WDI U6808B = 100 Hz WDI Unit ms 0 µA µA µA µs ms 0 µA µA 4 µ kHz ...
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... Protection against Transient Voltages According to ISO TR 7637-3 Level 4 (Except Pulse 5) Pulse Voltage 1 -110 V 2 +110 V 3a -160 V 3b +150 Relay driver: relay coil with R Note: 1. U6808B 8 = 100 kHz + 50% - 45%, f intern Test Conditions V = const. WDI V = const. WDI Source (1) Resistance Rise Time 10 100 V/s ...
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... Figure 6. Watchdog in Too-fast Condition Normal operation 5 V WDI Batt RELAY ENABLE 0 V Figure 7. Watchdog in Too-slow Condition Normal operation 5 V WDI Batt RELAY ENABLE 0 V 4707A–AUTO–05/03 WDI too fast Normal operation WDI too slow U6808B Don't care Normal operation Don't care 9 ...
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... Reset debounce time Figure 9. Undervoltage Condition 5 V < 4 Batt RELAY ENABLE RESET 0 V Reset debounce time U6808B 10 Overvoltage condition > 120 ms < 120 ms 3 good WDI pulses st 1 Reset delay nd 2 Reset delay Undervoltage condition > 120 ms < 120 ms 3 good WDI pulses st 1 ...
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... Package Information Package SO8 Dimensions in mm 4707A–AUTO–05/ 100 0.01 mF U6808B Relay mC V Batt Package SO8 5.00 4.85 1.4 0.25 0.4 0.10 1.27 3. osc osc 3.3 nF Remarks – 5.2 4.8 3.7 0.2 3.8 6.15 5.85 technical drawings according to DIN specifications U6808B 11 ...
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... 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. ...