Electronic Components Datasheet Search |
|
UJA1061 Datasheet(PDF) 10 Page - NXP Semiconductors |
|
UJA1061 Datasheet(HTML) 10 Page - NXP Semiconductors |
10 / 81 page 2004 Mar 22 10 Philips Semiconductors Objective specification Low speed CAN/LIN system basis chip UJA1061 Being in Normal mode, Start-up mode will be entered if: • A wrong mode register code access occurs • On too-late or too-early watchdog triggering • After an ignored interrupt (same as an ignored interrupt in Standby mode) • Flash mode entry sequence is written to the mode register • During a pending wake-up when the microcontroller did request a mode change to Sleep mode. Being in Flash mode, Start-up mode will be entered if: • A wrong mode register code access occurs • On a watchdog trigger overflow (too late) • After an ignored interrupt (same as an ignored interrupt in Standby mode). When entering Start-up mode, the reset source information is provided by the UJA1061 in order to support different software initialization cycles that depend on the reset event. 6.2.3 RESTART MODE The intention of the Restart mode is to give the application a second opportunity to start-up, if the first start-up has failed due to a certain failure. Restart mode will be entered out of the start-up as shown in the state diagram (see Fig.3). The events are as follows: • A watchdog initialization failure occurs (wrong mode register code or start-up time-out • An SPI failure (SPI count other than 16) occurs • A falling edge on pin RSTN occurs during the initialization phase in Start-up mode • A falling edge on pin RSTN occurs during start-up. Entering Restart mode will always lengthen the reset pulse to the long period in order to guarantee a proper reset length independent from history. If one of these failures still occurs after entering this mode; pin RSTN stays LOW or if the UJA1061 detects an undervoltage on V1 after an already released pin RSTN, Fail Safe mode will be entered. If the failure has been removed during Restart mode and the watchdog initialization has been successful, the selected operating mode will be entered. The only correct watchdog initialization out of Restart mode is the SPI access of the Mode register, whereby the init Normal mode has been selected. 6.2.4 NORMAL MODE The Normal mode is entered after the following events (see Fig.3): • Watchdog initialization has been executed successfully after an init Normal mode access of the mode register out of Start-up or Restart mode • Out of Standby mode via an SPI command. In this mode the UJA1061 allows access to all system resources such as CAN, LIN, INH and EN and therefore requires accurate watchdog triggering using the Window mode with programmable windows. Upon any false watchdog trigger, a system reset is performed. Interrupts to the host microcontroller initiated by the UJA1061 are also observed. A system reset is performed if the host microcontroller does not react within 256 ms. Entering Normal mode does not activate the CAN physical layer automatically. A certain bit (CAN mode) is used to activate the CAN medium if desired, enabling local cyclic wake-up scenarios to be implemented without affecting the CAN physical layer. 6.2.5 STANDBY MODE Standby mode sets the system into a state with reduced current consumption. Entering Standby mode will automatically clear the CAN mode bit, thus allowing the CAN physical layer to enter the Low-power mode autonomously. However, the watchdog still monitors the microcontroller (Time-out mode) since it is powered via pin V1. In case the host microcontroller can provide a Low-power mode with reduced current consumption in its standby or stop mode, the watchdog can be switched-off entirely within Standby mode of the UJA1061. The UJA1061 monitors the microcontroller supply current to make sure that there is no unobserved phase with disabled watchdog and running microcontroller. The watchdog will keep active until the supply current drops below a certain limit. Below this current limit the watchdog is disabled. If the current increases again, e.g. caused by a microcontroller wake-up from application-specific hardware, the watchdog starts operation again with the previously-used time-out period. A system reset can be performed if programmed accordingly, in this case Start-up mode is entered. |
Similar Part No. - UJA1061 |
|
Similar Description - UJA1061 |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.COM |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Datasheet Upload | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |