TLE7368

Overview

Data Sheet

4

Rev. 1.1, 2007-11-08

Description

The TLE7368 device is a multifunctional power supply circuit especially designed for Automotive powertrain

systems using a standard 12 V battery. The device is intended to supply and monitor next generation 32-bit

microcontroller families (13

µm lithography) where voltage levels such as 5 V, 3.3 V or 1.5 V are required.

The regulator follows the concept of its predecessor TLE6368/SONIC, where the output of a pre-regulator feeds

the inputs of the micro’s linear supplies. In detail, the TLE7368 cascades a Buck converter with linear regulators

and voltage followers to achieve lowest power dissipation. This configuration allows to power the application even

at high ambient temperatures.

The step-down converter delivers a pre-regulated voltage of 5.5 V with a minimum peak current capability of 2.5 A.

Supplied by this step down converter two low drop linear post-regulators offer 5 V and 3.3 V (2.6 V) with high

accuracy. The current capability of the regulators is 800 mA and 700 mA. The 3.3 V (2.6 V) linear regulator does

have its own input allowing to insert a dropper from the Buck output to reduce the on chip power dissipation if

necessary. For the same reason, reduction of on chip power dissipation, the 1.5 V core supply follows the concept

of integrated control circuit with external power stage.

Implementing the on board and microcontroller supplies in this way described, allows operation even at high

ambient temperatures.

The regulator system contains the so called power sequencing function which provides a controlled power up

sequence of the three output voltages.

In addition to the main regulators the inputs of two voltage trackers are connected to the 5.5 V Buck converter

output voltage. Their protected outputs follow the main 5 V linear regulator with high accuracy and are able to drive

loads of 50 mA and 105 mA.

To monitor the output voltage levels of each of the linear regulators two independent undervoltage detection

circuits are available. They can be used to implement the reset or an interrupt function.

For energy saving reasons, e.g. while the motor is turned off, the TLE7368 offers a stand-by mode. The stand by

mode can be enabled and disabled either by battery or the microcontroller. In this stand-by mode just the stand-

by regulator remains active and the current drawn from battery is reduced to a minimum for extended battery

lifetime. A selection pin allows to configure the output voltages of the stand-by regulator to the application’s needs.

The input of the stand-by regulator is separated from the high power input of the pre-/post-regulator system.

The TLE7368 is based on Infineon’s Power technology SPT™ which allows bipolar, CMOS and power DMOS

circuitry to be integrated on the same monolithic chip/circuitry.