1

2

3

4

5

6

7

8

Top View

Narrow Body

TX

FAULT

K

GND

SO Package

CS

RX

Si9241AEY

Vishay Siliconix

www.vishay.com

4

Document Number: 70787

S-02936—Rev. D, 22-Jan-01

PIN CONFIGURATION

ORDERING INFORMATION

Part Number

Temperature Range

Si9241AEY

–40 to 125

_C

PIN DESCRIPTION

Pin Number

Symbol

Description

1

Positive Power Supply

2

TX

Transmit, Input

3

CS

Chip Select, Input

4

FAULT

Fault, Open Drain Output

5

GND

Ground Connection

6

K

Transmit/Receive, Bidirectional

7

Battery Power Supply

8

RX

Receiver, Output

FUNCTIONAL DESCRIPTION

The Si9241AEY can be either in transmit or receive mode and

detection circuits.

output will be “high.”

In order to be in transmit mode, CS must be set “low.” When

CS and TX are set “low” the internal MOSFET will turn on,

causing the K pin to be “low.” In the transmit mode, the

processor monitors RX and TX. When the two mirror each

other there is no fault. In the event of over temperature, or short

protect the IC and the external open drain FAULT pin will be

asserted. The K pin will stay in high impedance and RX will

follow the K pin. The fault will be reset when CS is toggled high.

while the K pin has internal pull down resistors. When any one

When CS is set “high” the Si9241AEY is in receive mode and

the internal MOSFET for the K pin is turned off. The RX output

will follow the K pin. If CS is “low” while the IC is receiving data,

an incorrect fault signal will occur.

To inhibit the short detect, tie CS and TX together.