Doc ID16895 Rev 2

11/24

AN3126

DAC main features

23

Figure 7. Noise waveform with changeable offset

1.7.2

Typical applications

The STM32 microcontrollers come with 12-bit enhanced ADC with a sampling rate of up to

1 M samples/s. In most applications, this resolution is sufficient, but in some cases where

higher accuracy is required, the concept of oversampling and decimating the input signal

can be implemented to save the use of an external ADC solution and to reduce the

application power consumption.

More details about these methods are explained in the application note AN2668, in the

section titled “Oversampling using white noise”.

White noise generator can be also used in the production of electronic music, usually either

directly or as an input for a filter to create other types of noise signal. It is used extensively in

audio synthesis, typically to recreate percussive instruments such as cymbals which have

high noise content in their frequency domain.

White noise generator can be used for control engineering purposes, it can be used for

frequency response testing of amplifiers and electronic filters.

White noise is a common synthetic noise source used for sound masking by a Tinnitus

masker.

1.8

Triangular wave generator

1.8.1

Definition

The STM32 DAC provides the user with a triangular waveform generator with a flexible

offset, amplitude and frequency.

Theoretically, a triangular waveform is a wave form comprised of an infinite set of odd

harmonic sine waves (see Figure 9).

The amplitude of the triangular waveform can be fixed using the MAMPx bits in the

DAC_CR register.

ai18306

Noise waveform

Pattern waveform (offset)

Result waveform