R

EM6153

Copyright © 2006, EM Microelectronic-Marin SA

1

www.emmicroelectronic.com

06/06, rev. B, prelim.

5V Automotive Regulator with Inhibit Input and

Windowed Watchdog

Description

The EM6153 offers a high level of integration by combining

voltage

regulation,

voltage

monitoring

and

software

monitoring using a windowed watchdog.

regulated output voltage as low as 1.2 V. The watchdog

function monitors software cycle time and execution.

If software clears the watchdog too quickly (incorrect cycle

time) or too slowly (incorrect execution) it will cause the

system to be reset. For enhanced security, the watchdog

must be serviced within an “open” time window. During the

remaining time, the watchdog time window is “closed” and a

watchdog during this “closed” time window. The ratio of the

open/closed window is either 33%/67% or 67%/33%.

The system ENABLE output prevents critical control functions

being activated until software has successfully cleared the

watchdog three times. Such a security could be used to

prevent motor controls being energized on repeated resets of

a faulty system.

When the microcontroller goes in stand-by mode or stops

EM6153 (version 55) goes into a stand-by mode in order to

save power (CAN-bus sleep detector).

In EM6153, the voltage regulator has a low dropout voltage

and a low quiescent current of 75

μA. The quiescent current

increases only slightly in dropout prolonging battery life. Built-

in protection includes a positive transient absorber for up to

45 V (load dump) and the ability to survive an unregulated

input voltage of -42 V (reverse battery). The input may be

connected to ground or to a reverse voltage without reverse

current flowing from the output to the input.

Features

Low quiescent current 90

μA

Very low OFF current consumption < 1uA

-40°C to +125°C temperature range

Highly accurate 5 V, 150 mA guaranteed output (actual

maximum current depends on power dissipation)

Low dropout voltage, typically 250 mV at 100 mA

Unregulated DC input can withstand -42 V reverse battery

and +45 V power transients

Fully operational for unregulated DC input voltage up to

40 V and regulated output voltage down to 3.5 V

No reverse output current

Very low temperature coefficient for the regulated output

Current limiting

Windowed watchdog with an adjustable time windows,

guaranteeing a minimum time and a maximum time

between software clearing of the watchdog

Time base accuracy

±8% (at 100ms)

Sleep mode function (V55)

Adjustable threshold voltage using external resistors

Adjustable power on reset (POR) delay using one

external resistor

Open-drain active-low RESET output

Reset output guaranteed for regulated output voltage

down to 1.2 V

System ENABLE output offers added security

Qualified according to AEC-Q100

Green SO-16 Exposed pad package (RoHS compliant)

Applications

Automotive systems

Industrial

Home security systems

Telecom / Networking

Computers

Set top boxes

Typical Operating Configuration

Fig. 1

Selection Table

Part Number

Closed

Window

Open

Window

CAN-bus sleep

detector

EM6153V50

1.52 V

67%

33%

NO

EM6153V53

1.52 V

33%

67%

NO

EM6153V55

1.275 V

67%

33%

YES

Please refer to Fig. 4 for more information about the

open/closed window of the watchdog.

5V

+

V

SS

GND

Unregulated

Voltage

INPUT

OUTPUT

EM6153

RES

EN

TCL

V

IN

V

DD

I/O

RES

I/O

R

OSC

10uF

100nF

22uF

R

OSC

R

1

R

2

+

INH

Inhibit

V

DD