ata6621n ATMEL Corporation, ata6621n Datasheet - Page 11

• Manufacturer Part Number: ata6621n
• Description: Lin Transceiver With 5v Regulator And Watchdog
• Manufacturer: ATMEL Corporation

3.15.6
3.16
3.16.1
3.16.2
3.16.3
4887H–AUTO–12/07
Wake-up Scenarios from Silent or Sleep Mode
Debug Mode
Remote Wake-up via Dominant Bus State
Local Wake-up via Pin Wake
Wake-up Source Recognition
The watchdog is switched off with pin MODE high (5V) and in normal operation if it is tied to
GND (see
Table 3-1.
A falling edge at pin LIN followed by a dominant bus level maintained for a certain time period
(t
voltage regulator is activated, and the internal slave termination resistor is switched on. The
remote wake-up request is indicated by a low level at pin RXD to generate an interrupt in the
microcontroller and a high level at pin TXD. The watchdog needs a trigger signal from PTRIG or
NTRIG within the lead time t
A falling edge at pin WAKE followed by a low level maintained for a certain time period (t
results in a local wake-up request. The extra long wake-up time (t
sients as defined in ISO7637 create a wake-up. The device switches to Pre-normal mode. The
internal slave termination resistor is switched on. The local wake-up request is indicated by a low
level at pin RXD to generate an interrupt in the microcontroller and a low level at pin TXD. The
watchdog needs a trigger signal from PTRIG or NTRIG within the lead time t
NRES.
The device can distinguish between a local wake-up request (pin WAKE) and a remote wake-up
request (dominant LIN bus state). The wake-up source can be read on pin TXD in Pre-normal
mode. A high level indicates a remote wake-up request and a low level indicates a local wake-up
request. The wake-up request flag (signalled on pin RXD) as well as the wake-up source flag
(signalled on pin TXD) are reset immediately, if the microcontroller sets pin EN to high
3-3 on page
If the ATA6621N is in Sleep mode or Silent mode and the voltage at the LIN Bus falls to a value
lower than VLINL < V
remains higher than 0.6
the pins RXD and TXD
BUS
Pre-normal
Operation
Mode of
) results in a remote wake-up request. The device switches to Pre-normal mode. The V
Normal
Sleep
Silent
Figure 5-2 on page
8).
Table of Modes
Transceiver
Off
On
Off
Off
S
(Figure 3-6 on page
– 3.3V) (see
V
D
S
, a local wake-up is indicated after the time t
to avoid resets at NRES.
24).
VCC
5V
5V
5V
0V
“Electrical Characteristics”
12).
WD_OSC
2.5V
2.5V
0V
0V
(Figure 3-3 on page
TEMP
2V
2V
0V
0V
WAKE
numbers 9.5 and 9.6) but
) ensures that no tran-
RXD
WAKE
5V
5V
5V
0V
ATA6621N
8)
D
to avoid resets at
by a low level at
RECESSIVE
RECESSIVE
RECESSIVE
RECESSIVE
LIN
(Figure
WAKE
11
CC
)