STM32F4DISCOVERY
Hardware and layout
Doc ID 022256 Rev 2
17/38
4.6
On board audio capability
The STM32F4 uses an audio DAC (CS43L22) to output sounds through the audio mini jack
connector.
The STM32F4 controls the audio DAC through the I2C interface and processes digital
signals through 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 STM32F4.
●
The sound can be output in different ways through audio DAC:
–
Using I2S protocol
–
Using the STM32F4 DAC to analog input AIN1x of the CS43L22
–
Using the microphone output directly via a low pass filter to analog input AIN4x of
the CS43L22
4.7
USB OTG supported
The STM32F4 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 connected device
4.8
Motion sensor (ST MEMS LIS302DL)
The LIS302DL is an ultra compact low-power three-axis linear accelerometer.
It includes a sensing element and an IC interface able to provide the measured acceleration
to the external world through I2C/SPI serial interface.
The LIS302DL has dynamically user selectable full scales of ±2g/±8g and it is capable of
measuring acceleration with an output data rate of 100 Hz or 400 Hz.
The STM32F4 controls this motion sensor through the SPI interface.
4.9
JP1 (Idd)
Jumper JP1, labeled Idd, allows the consumption of STM32F407VGT6 to be measured by
removing the jumper and connecting an ammeter.
●
Jumper on: STM32F407VGT6 is powered (default).
●
Jumper off: an ammeter must be connected to measure the STM32F407VGT6 current,
(if there is no ammeter, the STM32F407VGT6 is not powered).
