33794

MOTOROLA ANALOG INTEGRATED CIRCUIT DEVICE DATA

6

LAMP_CTRL

1

PWR_MON

LP_CAP

R_OSC

NC

NC

NC

NC

CLK

LEVEL

11

12

13

14

15

16

17

18

19

20

9

10

21

22

23

24

25

26

27

6

7

8

4

5

DIS_SHIELD

D

C

B

A

SIGNAL

NC

LAMP_SENSE

LAMP_MON

NC

LAMP_GND

NC

2

3

54

44

43

42

41

40

39

38

37

36

35

46

45

34

33

32

31

30

29

28

49

48

47

51

50

53

52

RST

WD_IN

NC

E3

E2

E1

TEST

NC

NC

GND

NC

SHIELD

AGND

E4

REF_A

E9

E8

E7

E6

E5

NC

ISO_OUT

REF_B

NC

ISO_IN

NC

LAMP_OUT

ISO-9414

SOICW-EP PIN FUNCTION DESCRIPTION

Pin

Pin Name

Formal Name

Definition

1

RST

Reset

This output is intended to generate the reset function of a typical MCU. It has a delay

low, and a watchdog timer that will force a reset if WD_IN is not asserted at regular

intervals. Timing is derived from the oscillator and will change with changes in the

resistor attached to R_OSC.

2

WD_IN

Watchdog In

from being asserted. By having the MCU program perform this operation more often

the allowed time, a check that the MCU is running and executing its program is

assured. If this doesn’t occur, the MCU will be reset. If the watchdog function is not

desired, this pin may be connected to CLK to prevent a reset from being issued.

3, 5, 7,

20–23, 31,

33, 34,

48–50, 52

NC

No connect

These pins may be used at some future date and should be left open.

4

LAMP_GND

Lamp Ground

This is the ground for the current from the lamp. The current into LAMP_OUT flows

out through this pin.

6

LAMP_CTRL

Lamp Control

This signal is used to control the lamp driver. A high logic level turns on the lamp.

8

LAMP_SENSE

Lamp Sense

This pin is normally connected to the LAMP_OUT pin. The voltage at this pin is

reduced and sent to LAMP_MON so the voltage at the lamp pin is brought into the

range of the analog-to-digital converter (ADC) in the MCU.

9

LAMP_MON

Lamp Monitor

This pin is connected through a voltage divider to the LAMP_SENSE pin. The

voltage divider scales the voltage at this pin so that battery voltage present when the

lamp is off is scaled to the range of the MCU ADC. With the lamp off, this pin will be

very close to battery voltage if the lamp is not burned out and the pin is not shorted

to ground. This is useful as a lamp check.