U5021M-NFPY Atmel, U5021M-NFPY Datasheet
U5021M-NFPY
Specifications of U5021M-NFPY
Related parts for U5021M-NFPY
U5021M-NFPY Summary of contents
Page 1
... Enable Output 1. Description The digital window watchdog timer, U5021M CMOS integrated circuit. In applica- tions where safety is critical especially important to monitor the microcontroller. Normal microcontroller operation is indicated by a cyclically transmitted trigger signal, which is received by a window watchdog timer within a defined time window. ...
Page 2
... Figure 1-1. Block Diagram with External Ciruit OSC Reset 5 Micro- controller 2 Trigger 3 Mode 1 Wake-up 2. Pin Configuration Figure 2-1. Pinning SO8 U5021M Oscillator OSC State machine OSC Input signal conditioning Power-on POR POR reset 7 GND 1 WAKE-UP 2 TRIG MODE 3 ENA 4 External 4 switching circuitry ...
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... VDD Supply voltage 7 GND Ground, reference voltage 8 OSC RC oscillator 4. Functional Description 4.1 Supply Voltage, Pin 6 The U5021M requires a stabilized supply voltage V characteristics. An external buffer capacitor may be connected between pin 6 and GND. 4.2 RC Oscillator, Pin 8 The clock frequency, f, can be adjusted by the components where ...
Page 4
... The switch-over mode time enables the synchronous operation of microcontroller and watchdog. When the power-on reset time has elapsed, the watchdog has to be switched to monitoring mode by the microcontroller by a “low” signal transmitted to the mode pin (pin 3) within the time-out period, t erates a reset pulse, t the switch-over mode time, t U5021M 4 = 500 ...
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... The positive edge of the trigger signal , (enable time). The 3 2 Pin 6 Pin Pin 3 Pin ensure correct operation of the micro and an enable time which a trigger sig U5021M 5 ...
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... Wake-up Mode Trigger Enable 5. State Diagram The kernel of the watchdog is a finite state machine. possible states and transmissions. Many transmissions are controlled by an internal timer. The numbers for the time-outs are the same as on the pulse diagrams. U5021M shows the switch-over from the short to the long watchdog mode. The wake-up signal ...
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... Short window disable state time out t 2 trg_ok = 1 mode = 1 Short window enable state time out t 3 trg_err = 1 trg_err = 1 time out wedge = 1 mode = 1 Long window disable state mode = 0 time out t 4 trg_ok = 1 mode = 0 Long window enable state trg = 0 or wedge = 1 U5021M 7 ...
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... RST Inputs Logical “high” Logical “low” Hysteresis Input voltage range Input current Input current Outputs Maximum output current Logical output “low” I OUT Logical output “high” I OUT Leakage current V OUT U5021M 8 Symbol OUT amb T stg Symbol R thJA Pin ...
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... Disable time Long watchdog window Enable time Long watchdog window Reset-out time Note: 1. Frequency deviation also depends on the tolerances of the external components 9. Ordering Information Extended Type Number U5021M-NFPY U5021M-NFPG3Y 10. Package Information Package SO8 Dimensions in mm 4756D–AUTO–11/05 Pin = 470 pF, ...
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... Please note that the following page numbers referred to in this section refer to the specific revision mentioned, not to this document. Revision No. 4756D-AUTO-11/05 4756C-AUTO-09/04 4756B-AUTO-07/04 U5021M 10 History Put datasheet in a new template First page: Pb-free logo added Page 7: figure 5-1 changed Page 9: Ordering Information changed Electrical Characteristics Table, page 8, row “ ...
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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 ...