To Next Page

To Previous Page

DocID025174 Rev 1 19/39

UM1669 Hardware layout

4.6 On board audio capability

The STM32F401 uses an audio DAC (CS43L22) to output sounds through the audio mini

jack connector.

The STM32F401 controls the audio DAC through the I2C interface and processes digital

signals through an I2S connection or analog input signal.

• The sound can come independently from different inputs:

– ST MEMS microphone (MP45DT02): digital using PDM protocol or analog when

using the low pass filter.

– USB connector: from external mass storage such as a USB key, USB HDD, and

so on.

– Internal memory of the STM32F401.

• The sound can be output in different ways through audio DAC:

– Using the I2S protocol

– Using the microphone output directly via a low pass filter to analog input AIN4x of

the CS43L22

4.7 USB OTG supported

The STM32F401 is used to drive only USB OTG full speed on this board. The USB micro-

AB connector (CN5) allows the user to connect a host or device component, such as a USB

key, mouse, and so on.

Two LEDs are dedicated to this module:

• LD7 (green LED) indicates when VBUS is active

• LD8 (red LED) indicates an overcurrent from a connected device.

4.8 E-compass MEMS (ST MEMS LSM303DLHC)

The LSM303DLHC is an ultra-compact low-power system-in-package featuring a 3D digital

linear acceleration sensor and a 3D digital magnetic sensor. It includes a sensing element

and an IC interface able to provide the measured acceleration to the external world through

an I2C serial interface.

The LSM303DLHC has dynamically user-selectable full scales of ± 2g/± 8g and is capable

of measuring the acceleration, and a magnetic field full scale from ±1.3 g to 8.1 g with an

output data rate of 100 Hz or 400 Hz.

The STM32F401VCT6 MCU controls this motion sensor through the I2C interface.

4.9 Gyroscope MEMS (ST MEMS L3GD20)

The L3GD20 is an ultra-compact, low-power, three-axis angular rate sensor. It includes a

sensing element and an IC interface able to provide the measured angular rate to the

external world through the I2C/SPI serial interface.

The L3GD20 has dynamically user-selectable full scales of ± 250 dps/500 dps/±2000 dps

and is capable of measuring rates.

ST STM32F401 User Manual

Questions and Answers: