Rainbow Electronics ATA6834 - Manual (Page 12)

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9122B–AUTO–10/08
ATA6833/ATA6834 [Preliminary]
3.10 Diagnostic Outputs D1 - D3
As mentioned in the sections above, the diagnostic outputs DG1 to DG3 are used to signal fail-
ures. This is summarized in the following table.
In order to differentiate between LIN and EN2 wake-up, DG1 output will be set to LOW or HIGH
respectively. LOW indicates wake-up by LIN, HIGH indicates wake-up by EN2. DG1 output will
be cleared by the first valid watchdog trigger after wake-up or by the first rising edge at one of
the control inputs (IL1 to IL3 and IH1 toIH3) if the watchdog is disabled.
3.11 LIN Transceiver
ATA6833 and ATA6834 include a fully integrated LIN transceiver complying with LIN specifica-
tion 2.1 and SAEJ2602 2. The transceiver consists of a low-side driver with slew rate control,
wave shaping, current limiting, and a high voltage comparator followed by a debouncing unit in
the receiver.
During transmission, the data applied at pin TXD will be transferred to the bus driver to generate
a bus signal on LIN pin. TXD input has an internal pull-up resistor.
To minimize the electromagnetic emission of the bus line, the bus driver has a built-in slew rate
control and wave-shaping unit. The transmission will be aborted by a thermal shutdown or by a
transition to Sleep Mode.
Table 3-2. Status of the Diagnostic Outputs (Normal Operation)
Device Status Diagnostic Outputs Comments
CPOK OT1 OV UV SC DG1 DG2 DG3
0 X X X X – 1 – Charge pump failure
X 1 X X X – – 1 Overtemperature prewarning
X X 1 X X – 1 – Overvoltage
X X X 1 X – 1 – Undervoltage
X X X X 1 1 – – Short circuit
Note: X represents: no effect)
OT1: overtemperature warning
OV: overvoltage of PBAT
UV: undervoltage of PBAT
SC: short circuit
CPOK: charge pump OK
Table 3-3. Indicating Wake-up Source
Diagnostic Outputs
Wake-up Source DG1 DG2 DG3
1 – – EN2
0 – – LIN