Datasheet

Data Sheet 14 Rev. 1.0, 2012-05-07

IFX4949

Application Information

5 Application Information

Note: The following information is given as a hint for the implementation of the device only and shall not be

regarded as a description or warranty of a certain functionality, condition or quality of the device.

Figure 3 Application Diagram

Note: This is a very simplified example of an application circuit. The function must be verified in the real application

5.1 Supply Voltage Transients

For many other voltage regulators fast supply voltage transients can often be the cause of unwanted reset output

signal perturbations. In contrast the IFX4949 shows a very high immunity of its reset output against such supply

voltage transients. Already starting from input voltages as low as 5.5 V the IFX4949 shows an immunity of the

reset output against supply transients of more than 100 V/µs even without an additional external capacitor at the

PRE pin

5.2 Functional Description

Description

The IFX4949 is a monolithic integrated low dropout voltage regulator. Several outstanding features and auxiliary

functions are implemented to meet the requirements of supplying microprocessor systems in all kinds of

applications. The modular approach of this device allows to get easily also other features and functions when

required.

1) Please note that also for the case of such input transients the absolute maximum ratings must not be violated.

2) The PRE pin of the IFX4949 offers the possibility to connect a bypass capacitor to GND to stabilize PRE output and to

optimize the transient behaviour. See also section “Preregulator ” on Page 16.

Application_diagram .vsd

Bandgap

Reference

Preregulator 5V

Reset

PRE

OUT

GND D

Batt