ATA6621 ATMEL Corporation, ATA6621 Datasheet - Page 5

• Manufacturer Part Number: ATA6621
• Manufacturer: ATMEL Corporation

3.7
3.8
3.9
3.10
3.11
4887B–AUTO–01/06
TXD Dominant Time-out Function
Output Pin (RXD)
Enable Input Pin (EN)
Wake Input Pin (WAKE)
MODE and TM Input Pins
The TXD input has an internal pull-up resistor. An internal timer prevents the bus line from being
driven permanently in the dominant state. If TXD is forced to low longer than t
LIN bus driver is switched to the recessive state.
This pin reports the state of the LIN bus to the microcontroller. LIN high (recessive state) is
reported by a high level at RXD, LIN low (dominant state) is reported by a low level at RXD. The
output has an internal pull-up structure with typically 5 k to V
defined with an external load capacitor of 20 pF.
The output is short-circuit protected. In Unpowered Mode (that is, V
This pin controls the operation mode of the interface. If EN is high, the interface is in Normal
Mode, with transmission paths from TXD to LIN and from LIN to RXD both being active. The V
voltage regulator is operating with 5V ±2%/50 mA output capability.
If EN is switched to low while TXD is still high, the device is forced to Silent Mode. No data trans-
mission is then possible and the current consumption is reduced to I
capability of the V
If EN is switched to low while TXD is low, the device is forced to Sleep Mode. No data transmis-
sion is possible and the voltage regulator is switched off.
This pin is a high voltage input used to wake the device up from Sleep Mode. It is usually con-
nected to an external switch in the application to generate a local wake-up. A pull-up current
source with typically 10 µA is implemented.
If you don’t need a local wake-up in your application, connect pin WAKE directly to pin VS.
These inputs are used for a special test mode of the watchdog in final production measurement
at Atmel. In the application, they are always connected to GND.
Wake-up events from Sleep Mode:
• LIN bus
• WAKE pin
• EN pin
CC
regulator is also 50 mA, but the V
CC
tolerance is between 4.65V and 5.35V.
CC
. The AC characteristics can be
S
= 0V), RXD is switched off.
VS
= 50 µA. The current
ATA6621
DOM
> 20 ms, the
CC
5