AS-Interface Slave IC

AS2701A (ISA3+)

Rev. C, October 2000

Page 13 of 16

Application Example 1:

Sensor/actuator circuit supplied by the AS-Interface Slave IC (UOUT) for supply current needs

ASI-Slave-IC

1

G1

C1

C3

C5

C2

C4

ASI Line

ASI-N

V2

V1

1

ASI-P

C1 = 22...470 nF / max. AS-Interface BUS DC voltage

C2 = 10...220 nF / max VU5R = 5.5 V

C3 = 10...470 µF / max. (VUOUT + VUOUTp) = 29.1 V

C4 = 22...100 nF / max. (VUOUT + VUOUTp + 1.4 V) = 30.5 V

C5 = 10...100 nF (close to the IC) / max. (VUOUT + VUOUTp) = 29.1 V

V1 = 1N4002 or equivalent

V2 = TGL 41-39A or equivalent

G1 = AS-Interface Crystal 5.333 MHz

For V2 a limiter diode with a small capacitance value should be selected, to ensure that the

AS-Interface Bus can be operated with the maximum number of Slave units connected.

In a more general sense care should be taken that the pc board tracks and the external

components between the AS-Interface Bus and LTGP / LTGN contribute to the AS-Interface

Slave unit's input impedance inductively and highly resistively, rather than capacitively.