L9409

Device description

Doc ID 022665 Rev 2

9/13

4.3

Lamp and relay driver

4.3.1

Description

The lamp driver has two functions:

●

Switch on the warning lamp in the dash board when any of fault operation occurs.

●

Judge if IG-SW is turned on or not.

4.3.2

Electrical characteristic

4.3.3

Relay driver description

This terminal is used to provide a current to electric loads such as a Relay coil connected

between L terminal and GND. While L terminal is turned off, a current of max. 2.5 A is

provided to the relay coil, using a high side driver, between R terminal and L terminal, after a

time delay of 300 µs. The R terminal can be connected to the ignition switch, B terminal or it

can be left open.

4.3.4

Electrical characteristic

Table 8.

Electrical characteristics

Symbol

Parameter

Test condition

Min.

Typ.

Max.

Unit

Lamp driver saturation voltage

1.2

-

1.4

1.2

-

1.45

V

1.2

-

1.50

V

Lamp on voltage

4.7

-

6.2

V

4.5

-

5.5

V

3.5

-

5

V

Limitation lamp current

-

-

-

2.5

A

Wake-up voltage at L terminal

-

0.8

1

1.1

V

Pull down current

0.8

-

3

mA

Table 9.

Electrical characteristics

Symbol

Parameter

Test condition

Min.

Typ.

Max.

Unit

Relay driver saturation voltage

0.2

-

0.6

V

Relay threshold current

-

1.3

-

2.5

A

Relay driver activation delay

-

-

300

-

µs