ATA6621 ATMEL Corporation, ATA6621 Datasheet - Page 9

• Manufacturer Part Number: ATA6621
• Manufacturer: ATMEL Corporation

3.12.4
3.12.5
4887B–AUTO–01/06
Pre Normal Mode
Unpowered Mode
Figure 3-4.
At system power-up the device automatically switches to Pre Normal Mode. The voltage regula-
tor is switched on V
to low for t
off and the watchdog is active. The ATA6621 stays in this mode until EN is switched to high.
If V
Pre Normal Mode.
If you connect battery voltage to the application circuit, the voltage at the VS pin increases due
to the block capacitor
age threshold V
output voltage reaches its nominal value after t
the load.
The NRES is low for the reset time delay t
Battery
NRES
(V
VCC
TXD
res
LIN
S
EN
< 4V) is powered down during Silent Mode or Sleep Mode, the IC powers up into
= 10 ms and sends a reset to the microcontroller. LIN communication is switched
Switch to Sleep Mode
S_th
, the IC mode changes from Unpowered Mode to Pre Normal Mode. The V
CC
(Figure 3-6 on page
= 5V ±2%/50 mA (see
T
LIN switches directly to recessive mode
d
Delay time Sleep Mode
_sleep = maximum 20 µs
T
d
= 3.2 µs
Mode Select window
reset
12). When V
Figure 3-6 on page
. During this time, no mode change is possible.
VCC
. This time depends on the V
S
becomes higher than the V
12). The NRES output switches
Sleep Mode
ATA6621
CC
capacitor and
S
undervolt-
CC
9