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Revision 2.3

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AS8525

Datasheet - Application In form atio n

Figure 10. Receive Mode Impulse Diagram

8.6 RX and TX Interface

8.6.1 Input TX

The 5V input TX controls directly the BUS level. LIN Transmitter acts like a slew-controlled level shifter. A dominant state (low) on TX leads to the

LIN bus being pulled low (dominant state) too. The TX pin has an internal active pull up connected to VCC. This guarantees that an open TX pin

generates a recessive BUS level.

Figure 11. TX Interface

8.6.2 Output RX

The received BUS signal will be output to the RX pin:

BUS < Vthr_cnt – 0.5 * Vthr_hys

→ RX = low

BUS > Vthr_cnt + 0.5 * Vthr_hys

→ RX = high

This output is a push-pull driver between VCC and GND with an output current of 1mA.

RX

BUS

40%

50%

60%

VCC

TX

AS8525

MCU

VCC

RC-Filter

(10ns)